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Old 08-11-2014, 05:21 PM   #381
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Quote:
Originally Posted by Ron Gratz View Post
Ford agrees that the rear should compress more than the front. In fact, Ford now specifies that the front axle load, when hitched with WD applied, should be less than the unhitched axle load.



Since 2010, Ford has specified that their F-series trucks should have the WDH adjusted to eliminate approximately 50% of the front end rise due to tongue weight. That corresponds to restoring approximately 50% of the load which was removed from the front axle.

When the WDH is properly adjusted, the front might be up about a half inch and the rear might be down 1-1.5" -- depending on tongue weight.

Too much load transfer to the front axle can lead to undesirable oversteer.



I think the reason Ford, Chevrolet, Toyota, Equal-i-zer, Reese and others have changed their weight distribution specifications is pretty well summed up in this Letter to Editor by Richard H Klein, P E printed in TRAILER BODY BUILDERS Magazine. The comment which specifically addresses front axle load is:



QUOTE

[blue]2. The statement “too much tongue weight can force the truck down in the back, causing the front wheels to lift to the point where steering response and braking can be severely decreased” is not the real issue with heavy tongue weights. The real problem is that the tow vehicle's yaw stability, as measured by “understeer gradient”, is severely decreased. This increases the propensity of the tow vehicle to jackknife in turning maneuvers. Specifically, recent full scale testing conducted by the SAE Tow Vehicle Trailer Rating Committee (and now published in SAE J2807), determined that the use of weight distributing hitch torque should be minimized. In fact they recommend that the Front Axle Load Restoration (FALR) not exceed 100% (100% means that the front axle weight is brought back, via weight distribution, to a weight equal to its “no trailer” condition).[/blue]

UNQUOTE



A related explanation from a representative of the company which manufactures the Equal-i-zer hitch was first posted here. It says:



QUOTE

[blue]In the past we had suggested that you should see a small drop on the front suspension. We are always trying to improve things here at Progress – our motto is “Safe and Happy Customers,” and so we are always reviewing our instructions and installation process. Recently, as part of this constant effort our engineers looked more deeply into this aspect of installation. We had always felt that a small drop was a sign that the trailer’s weight was being transferred to the front axle, and that this was essentially a good thing.



As our engineers reviewed the instructions for the last round of renewal of our instructions, the{y} found research results that contradicted our prior thinking. There has been a substantial amount of testing conducted by experts from SAE and the RV Industry Association to find out what will produce the best stability when towing. This towing suggests that you want your front axle’s compression to be close to, but not lower than your free-standing height.[/blue] (Underline added for emphasis.)

UNQUOTE



Ford says the Front Axle Load Restoration should be approximately 50%.



Chevrolet/GMC says the FALR should be 100%, 50% or 0% depending on TV model and TT weight.



Reese now includes the following in some of their WDH installation instructions:

[blue]8. A new term in the industry is (“FALR” – Front Axle Load Return).

100% FALR Means the front fender is returned to the preload position.

That is our recommendation for best performance.[/blue]



Equal-i-zer says the Front Axle Load Restoration should be between 50% and 100%.



Equal-i-zer's revised instructions specifically state:

[blue]Good adjustment:

You have most likely achieved good weight distribution adjustment if your measurements show the following with the trailer coupled and the weight distribution engaged:

1. From the coupled without weight distribution measurement, the front wheel well measurement is at least halfway back to the original uncoupled measurement. See line C on Front Wheel Well Measure Chart.

2. The rear wheel well measurement is somewhere between the uncoupled height, and the coupled with no weight distribution height. It should NEVER be higher than the uncoupled height. See line C on Rear Wheel Well Measure Chart. See Figure 19.[/blue]



Ron

Thank you Ron.

This is very useful information.

-evan


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Old 08-11-2014, 05:49 PM   #382
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Originally Posted by eheffa View Post
Thank you Ron.

This is very useful information.

-evan
Agreed. Makes me feel better about the 600#.

Also, not sure of the proper procedure but I did all the measurements with about half of the load we will put in the trailer and no passengers in the truck. We will have three passengers on most trips. That said, combined weight is less than 300 pounds. But that should lower the front a tad I would think.
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Old 08-11-2014, 06:43 PM   #383
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I'm coming down pretty heavily on the "Show me your weight ticket" side of things, after our recent experience with weighing what we thought was a pretty well-distributed rig. It looks pretty good visually, but the scales tell me we still need to move some weight to the front axle and back onto the trailer axles to unload the rear axle of the truck.
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Old 08-11-2014, 06:51 PM   #384
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Quote:
Originally Posted by Ron Gratz View Post
Ford agrees that the rear should compress more than the front. In fact, Ford now specifies that the front axle load, when hitched with WD applied, should be less than the unhitched axle load.

Since 2010, Ford has specified that their F-series trucks should have the WDH adjusted to eliminate approximately 50% of the front end rise due to tongue weight. That corresponds to restoring approximately 50% of the load which was removed from the front axle.
When the WDH is properly adjusted, the front might be up about a half inch and the rear might be down 1-1.5" -- depending on tongue weight.
Too much load transfer to the front axle can lead to undesirable oversteer.


Ron
Maybe that is why I seem to get blinded at night by so many LD trucks and SUVs towing a trailer! The geometric change is likely more than 15% increase in the beam center...upwards. >2" raise on a 24" beam center.
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Old 08-11-2014, 09:22 PM   #385
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Maybe that is why I seem to get blinded at night by so many LD trucks and SUVs towing a trailer! The geometric change is likely more than 15% increase in the beam center...upwards. >2" raise on a 24" beam center.
Perhaps it would be good to estimate the effect of front/rear height differential on headlamp angle and then try to determine what amount of increased headlamp angle is too much.

A front/rear height differential of up to 2" is considered by some to be acceptable. If the differential is 2" and the wheelbase is 130", the TV would have a change in inclination of about 1.5%, about 0.9 degrees.

I've not found any US regulations pertaining to headlamp aiming angles. However, the UN Economic Commission for Europe has adopted Regulation No. 48 pertaining to
UNIFORM PROVISIONS CONCERNING THE APPROVAL OF VEHICLES WITH REGARD TO THE INSTALLATION OF LIGHTING AND LIGHT-SIGNALLING DEVICES.

If I interpret the document correctly, for vehicles towing trailers, the allowable variation in dipped-beam inclination is about 2.6%.

Therefore, it appears a typical US tow vehicle with a rear-end squat of 1-2" would not result in an unacceptable headlamp angle per the ECE regulation.

Ron
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Old 08-11-2014, 10:00 PM   #386
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Equal-i-zer Hitch Thread.

I see what might be a tendency of some that may perhaps take too much weight off of the rear axle.

Weight is a factor of traction and traction is a factor of stability.

My hitch, while a different brand and style from the subject of this thread is equipped with 1,000 lb bars that are more than capable of making the back of my 1/2 ton truck too light to the effect of negatively affecting overall safety even though the front of my trailer is somewhat heavy.

Breaking traction on the rear axle of a tow vehicle either upon acceleration or braking is not a good thing.
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Old 08-12-2014, 09:59 AM   #387
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Post #380 by Ron Gratz explains a lot. I was confused by Equalizer's new instructions. Now I know why the change. Evaluating my setup now....
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Old 08-12-2014, 04:01 PM   #388
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My Equal-i-zer Discoveries

As an Equal-i-zer owner since 2006, having towed 65,000 miles with it, and now having bought a new one, I thought I would share my findings and experience with the group. I was one of the contributors to SilverGate’s 2006 thread http://www.airforums.com/forums/f232...use-28204.html, that seemed to start this “over hitching” discussion, and I contributed a lengthy post to Jim Golden’s 2007 thread, http://www.airforums.com/forums/f464...ort-34484.html. Some of that last thread has been obsoleted by Equal-i-zer’s new installation instructions, the logic behind the new instructions was explained very well by Ron Gratz’s recent post, #380 in this thread.

The 2007 thread pointed out to all, the error in installing the hitch link plate bolt below the gas line. If you go to the Equal-i-zer site today, you can find a Special Install Guide for Airstream Trailers that tells installers to move the gas line below the link plate bolt.

In 2006, I purchased the hitch with the 1,000 pound bars, when some would have said that the 600 pound model would have been adequate. Now, I’m towing with a 2006 Lincoln Mark LT with HD towing package. The truck is rated for an 8,900 - 9,900 pound trailer weight (depending on where you look, owner's manual for the lower number, the higher number is stamped into the hitch) and 990 pounds of hitch weight using a weight distributing hitch. This is somewhat less that the F-150s of that year, because Ford softened the suspension to give the Lincoln a better ride.

Loaded for travel, our old 23’ Safari had a 750 pound tongue weight (actual measurement). After properly installing the hitch with the link plates at the maximum 32” distance, and achieving what I thought was good weight distribution and a level trailer through wheel height measurements alone, I made my first trip on a scale and found that my drive axle was 270 pounds over loaded. Thus began my constant tweaking of the hitch.

From that weight measurement until early this year when we sold the 23’ and bought the 27’, I continued to add washers until I was up to the maximum of eight, and I had moved the L-Brackets up to where my bars were no longer parallel to the frame, but instead pointed up at the back. Even then, on our last long trip (to Alaska in 2012), when the scales said we were properly loaded (truck and trailer axles not overloaded) and everything (truck and trailer) was pretty much parallel to the ground, the rear tires on the truck and the front tires on the trailer ran warmer than the others. I could see extra wear developing on those tires, and eventually had to replace all the trailer tires due to wear on that 16,000 mile trip. The trailer tires had less than 15,000 miles on them and were inspected at the Airstream Service Center when we left for Alaska—I just replaced the truck tires with 63,000 miles on them.

Now to me, that says that that trailer/tow vehicle combination was under hitched. Perhaps the Equal-i-zer with 1,000 lb bars would have been correct for a standard F-150 Possibly slightly over hitched on an F-250, and definitely over hitched on an F-350 dually.

I’ve since traded up to a new, bigger Airstream and a new Equal-i-zer hitch, but the same tow vehicle. In my next post I’ll talk about how I selected that hitch, and the initial set-up and performance so far.
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Old 08-13-2014, 04:04 PM   #389
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My Equal-i-zer Discoveries, Part 2

When we decided to move up this year from our 23’ to the 27’ FB FC, I was thinking of keeping the now well worn 10,000/1,000 lb. Equal-i-zer, but then the buyer of my trailer wanted the hitch as part of the deal. Now I had to make a selection of a new hitch and size, and that’s when I started thinking that even though the 10,000/1,000 lb. hitch theoretically would work for the new trailer as its weights are all below those numbers, would I be under hitched for the new trailer?

I had all the dry weights for each trailer (my old 23’ and the new 27’) provided by Airstream in the spec sheets, and I had all the loaded weights for my truck and 23’ Airstream from my many trips across the scales. Using those, I was able to estimate how much our water, propane, and cargo weights should be on the 27’ Airstream, and approximately how much the hitch weight would increase from the specified dry hitch weight. This gave me an expected hitch weight of 950 lbs. and a trailer axle weight of 6,800 lbs. Pretty close to my hitch rating, but well under my maximum trailer weight.

On the Equal-i-zer website, as some have pointed out, there is a calculator to help you choose the correct hitch for your truck and trailer. When you enter the above numbers into that calculator, and estimating another 150 - 200 pounds of cargo in the truck, the 14,000/1,400 lb. hitch is recommended. I tried a number of different combinations, and only when I had the truck completely unloaded did anything less that the 14,000/1,400 hitch come back, and then it was only one step down to the 12,000/1,200 lb. hitch. Needless to say I chose the 14,000/1,400 lb. hitch.

A lot of supervision from me during the hitch installation ensured that the new 14,000/1,400 lb. hitch was properly installed. The new hitch only came with six spacer washers, and I had all of them installed. When the installation was complete and we hitched-up, I was pretty amazed at how close the weight distribution dialed in. The only adjustment we had to make was dropping the hitch head to correct the trailer pitch. Truck looks good, bars are parallel to the frame, trailer is parallel to the ground. Here are the measurements:

Unhitched Front: 35.125”; Rear: 36.875”
Trailer On Front: 36.625” (+1.875”); Rear: 35” (-1.875”)
Bars On Front: 34.5” (-0.625”); Rear: 36.125” (-0.75”)
Return Front: 142%; Rear: 60%

So you can see why I was very excited about the weight distribution performance of the hitch. The front and rear compression is almost equal, only differing by 1/8”. I then drove on the scales:

Steer Axle: 3240 lbs. (-210 lbs. from GAWR)
Drive Axle: 3680 lbs. (-170 lbs. from GAWR)
Trailer: 6180 lbs. (-1420 lbs from trailer GVWR)
Total Truck: 6920 lbs. (-130 lbs from truck GVWR)
GCW: 13100 lbs. (-1400 lbs, from GCWR)

Now I was even more excited. Everything is under what I had estimated. These measurements were all made with the truck and trailer pretty much loaded for travel, with a full water tank and propane bottles. My only unknown is the hitch weight, because I don’t have access to a hitch scale anymore.

So now the data comes in (Post #380) and I can see that my front return is way too high. Some final thoughts, plans, and observations in my next post.
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Old 08-14-2014, 09:00 AM   #390
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One of the benefits of learning how to drive in the frozen north is that you learn fairly early that a balanced vehicle is more directionally stable than a vehicle that is loaded, say, tail heavy, where the back end wants to pass the front end in a loss of control situation. Extra weight on the back driving wheels may help you get going in a straight line on an icy road but the same extra weight turns into your enemy on a curve. The conclusions reached by the various manufacturers on the correct way to distribute weight on a long wheel base vehicle are puzzling. It would be interesting to see some actual test data that supports the opinions. Jim


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Old 08-14-2014, 12:14 PM   #391
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Jim,

I'm kind of with you on that. I like the fact that all four wheels on my truck have a good grip on the ground when hitched. The goal of getting only a 50% return means the front is treading more lightly than the back, and I too can see where that could cause problems. I have addressed that a little more in my last post of this series.

Randy
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Old 08-14-2014, 12:23 PM   #392
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My Equal-i-zer Discoveries, Part 3

Doing my research for writing this set of articles, I found this in my 2006 truck’s owner’s manual for setting up a load equalizing hitch:

Quote:
[With trailer unhitched] Measure the height of a reference point on the front and rear bumpers at the center of the vehicle.

Attach the trailer to the vehicle and adjust the hitch equalizers so that the front bumper height is within 1/2” of the reference point. After proper adjustment, the rear bumper should be no higher than in [the step above].
I had completely missed this in 2006 and instead went by Equal-i-zer’s instructions that were saying to get equal compression on the front and rear of the truck, or no more than an inch difference. As you read in part 2, equal compression or no more than an inch difference, is what I was going for when I set-up my new hitch, and I nailed it.

Having now towed over 65,000 miles with two different trailers and Equal-i-zer hitches both set-up this way, I have to say that I have never experienced anything but effortless towing. We have towed in all but three of the lower 48 states, Alaska, and 9 Canadian Provinces; climbed and safely descended numerous mountain grades; been passed by all manner of trucks, 18-wheelers, tour buses, etc.; through heavy rains and 50 mph cross winds crossing the Great Plains and never felt more than a small push against the truck and trailer. I’ve never detected any over or understeer on the truck from having the front return greater than 50%. In fact, the only noticeable difference in the truck when hitched (other than the load on the back) is that it tends to drift a little to the right when it doesn’t do than unhitched.

I’m now thinking, just thinking, that I may need to remove a spacer washer to reduce some of the front return, but I’m a little reluctant to do that for two reasons: (1) I don’t know if I can get the head bolts loose after watching the RV dealer hammer on them with the air wrench (or get them tight enough again with the tools I have), and (2) These are the best weight measurements on the truck axles that I have ever had. Why do I want to tinker with this when my driving experience and the scales say everything is great?

In a week, we are heading out on a two week, 1,500 mile trip, where our first night’s stop is at an exit with a CAT Scale. The opportunity is there to do some tinkering, but then I’d be spending that evening putting everything back if I didn’t like what I saw, so I’m still just thinking about it. I’ll let you know….

Two final thoughts to bring this discussion to a close. Whatever Progress Mfg. is building into the Equal-i-zer hitch to prevent and damp sway works. In my opinion, you don’t need any of those more expensive, complicated hitches if you’re planning to tow an Airstream. I know a lot of folks towing Airstreams with Equal-i-zers, some pulling 34’-ers with the same great results that I have seen.

Lastly, as far as over hitching my trailer tow vehicle combination, I’m going to trust the current thought and engineering science that Progress has put into their tool to help you select the proper hitch. On my old 23’ Airstream, we did repeatedly pop a few interior rivets, mostly at stress points like around the door, and after traveling some pretty rough roads. Those are easy to fix, and the ones we popped at other areas inside stayed fixed, so I don’t think the Airstream was taking a beating from the hitch, and I expect to have the same results with my new hitch and current tow vehicle. I don’t see me upgrading to a 3/4 ton truck in the future, but if I did, I’d run the tool again to see if my combination need re-thinking.

Hope this was helpful to you. Thanks for reading along,

Randy
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Old 08-14-2014, 03:48 PM   #393
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One of the benefits of learning how to drive in the frozen north is that you learn fairly early that a balanced vehicle is more directionally stable than a vehicle that is loaded, say, tail heavy, where the back end wants to pass the front end in a loss of control situation.---
Jim, the condition you describe ("where the back end wants to pass the front end") is called, "oversteer". Oversteer occurs when the front tires produce relatively too much lateral force toward the center of the turn and/or the rear tires produce relatively too little lateral force toward the center.

When you move the vehicle's center of gravity forward to "balance" the axle loads, you reduce the tendency toward oversteer.
Moving the CG foward increases the load on the front axle, but it also decreases the distance from CG to front axle.
The product of tires' lateral force times distance from axle to CG gives a steering torque which tends to yaw the vehicle about its CG.

If the tire's cornering stiffness coefficient (ratio of lateral force divided by vertical load) were a constant, the vehicle would remain in "neutral steer" -- the steering torques produced by front and rear axles would be equal magnitude and opposite direction. However, cornering stiffness coefficient decreases as the vertical load on the tire increases.

Therefore, moving the CG forward to "balance" the axle loads causes the front axle to produce relatively less steering torque and the rear axle to produce relatively more steering torque. This tends to keep the back end from wanting to pass the front end -- IOW the tendency for oversteer is reduced. In short --moving the TV's CG forward tends to decrease oversteer.

Now, let's attach a trailer to the TV. When rounding a curve, the trailer exerts an outward-directed lateral force on the ball. The trailer tends to make the TV turn toward the center of the turn -- increasing the tendency toward oversteer.

Fortunately, the trailer's tongue weight removes load from the TV's front axle and adds load to the rear axle. Since the location of the TV's CG does not change, the reduction of load on the front axle and the increase of load on the rear axle both tend to make the TV understeer.

If a WDH is used to add load to the front axle and remove load from the rear axle, the effect is to increase the tendency toward oversteer. If the WDH adds too much load to the front and removes too much from the rear, the TV might end up in an oversteer condition -- which is not desirable when towing a trailer.

In your "frozen north" scenario, we saw that moving the CG forward reduced the tendency toward oversteer.
When a trailer is attached to a TV, we see that reducing the amount of WDH load transfer also reduces the tendency toward oversteer.

Quote:
The conclusions reached by the various manufacturers on the correct way to distribute weight on a long wheel base vehicle are puzzling.---
It is important to keep in mind that "weight distrubution hitch" is a misnomer. A WDH does not distribute weight or mass. A WDH distributes load. If a WDH could magically redistribute some of the TV's mass, it could move the location of the TV's CG. Since a WDH cannot redistribute mass, the location of the TV's CG does not change.

You are correct that having a "balanced" vehicle tends to promote directional stability. However, "balanced" in this context, does not include the effect of tongue weight -- it only includes the effect of the distributed mass of the TV and its cargo.
Your desire to have a balanced TV, and the TV manufacturers' desire to reduce the amount of WDH load redistribution, are aimed at the same objective -- to improve the TV's directional stability.

Quote:
It would be interesting to see some actual test data that supports the opinions.
I don't know if the test results to which Richard Klein and the Progress Mfg. (Equal-i-zer) representative alluded are available for public distribution. If they are, they might be in an SAE report which could be purchased.

Ron
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Old 08-14-2014, 06:18 PM   #394
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Ron, thank you for your very thoughtful analysis of a condition that is difficult to understand. It's almost like a person where perfect does not exist but trying to get close is most likely good enough. Physics aside, once we through a human behind the wheel, perhaps attitude is the best ingredient for balance. I think SilverCabin will be just fine with his set up based on his methodology, attitude, and past performance. Jim


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Old 08-14-2014, 07:14 PM   #395
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Equal-i-zer Hitch Thread.

So, here's the tale of the scale for my rig. I went to my dealer and had the hitch adjusted, followed by a visit to the CAT scales.

So, here's what I'm seeing with nobody in the truck as we frantically measured and recorded data:

Measurement No TT TT no bars TT with bars
Front Bumper 24" 25.5" 24.5"
Front Wheel 36.5" 37" 36.5"
Rear Wheel 38" 35.25" 36.5"
Rear Bumper 29" 24.5" 26.75"

The truck had a nearly full gas tank and no cargo. The TT had full propane tanks, 1/2 full fresh water, empty grey/black tanks, and no food/clothes, etc. I was in the truck when weighing the rig, below.

When traveling, we'll be adding a couple of bicycles, my slim spouse and our golden retriever to the truck. We'll of course be adding clothes, food and water to the trailer. We will hit the CAT scales again after we load up for a camping trip as we head out for the weekend.

Here's the CAT scale ticket for my TV/TT shortly afterward. Looks like we have plenty of weight to play with and we're pretty well balanced. Previous weights (not on a CAT scale) indicated we had too much weight on the drive axle and that the front axle was 80 pounds lighter than without the TV. Given the other scales weren't CAT certified I won't cite them directly, but I will note that the relative values (e.g. various axle weights on the same scale) should be close enough to have given me useful information.

CAT values today:
Steer Axle 3,440 lbs (GAWR = 3,900)
Drive Axle 3,640 lbs (GAWR = 3,900)
Trailer Axle 5,960 lbs (Max acceptable trailer weight = 7,600)

Here's what we did that really changed the game for our truck: Lowered the hitch ball by one slot on the shank and added one washer.

We figured out today that the hitch ball was an inch or two higher than the coupler when the trailer was level. Our Ram has coil springs so it settles fast and looks OK once connected, but this mis-alignment must have caused the truck to carry more weight than ideal.

Adding the single washer pushed a bit more weight to the front of the truck and perhaps back to the trailer, giving us a more even distribution than before.

On the "before" config our trailer wasn't visibly nose-up, but the mis-alignment of ball height to coupler height must have caused the combined rig to put a lot more weight on the truck than it should have, while also lifting the steer axle of the truck enough to produce a noticeable high-headlights syndrome, even with the EQ hitch hooked up.

Lastly, the towing experience has improved dramatically. The headlights seem normal while towing, and the ride is considerably smoother. The ride continues to feel steady with no discernible sway even when being passed quickly by a double dump truck on a steep downhill run (e.g. I'm going 60 mph and he's going at a much higher but undetermined speed).

So, we're hopeful that we've dialed in the EQ hitch for our truck and trailer.
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Old 08-14-2014, 08:37 PM   #396
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Quote:
Originally Posted by Silvery Moon View Post
CAT values today:
Steer Axle 3,440 lbs (GAWR = 3,900)
Drive Axle 3,640 lbs (GAWR = 3,900)
Trailer Axle 5,960 lbs (Max acceptable trailer weight = 7,600)
Did you also measure the TV's axle loads today with the trailer unhitched?

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Old 08-14-2014, 10:46 PM   #397
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Great question.

Answer: No, though I knew it would be a good idea. I was flying solo and the truck stop was so crowded that I couldn't unhitch in their lot and try again. We'll catch that when we're loaded for the trip, probably on Saturday.

Uncertified weight for the truck alone from the other day, similarly equipped:
Steering axle: 3,420
Drive axle: 2,940
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Old 08-19-2014, 12:02 PM   #398
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I'd like to thank Ron publicly, for another very informative, explanatory post (#393). After carefully reading through that, I can understand why the current thought is to have more load on the rear of the TV than the front. Even though my setup seems balanced, in an emergency maneuver I can see how the trailer could drive the rear forward and cause a jackknife. Therefore, I have decided to remove a spacer washer.

I was a little surprised that I could get the head bolts loose with only two breaker bars. They were tight, but it didn't seem like 320 ft-lbs. Hope I can get them as tight as they need to be when I do the final tightening again.

I hitch-up and tow Monday. I'll be making measurements and a scale stop with a truck and trailer loaded for travel. Stay tuned for my next report.

Randy
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Old 08-19-2014, 07:16 PM   #399
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Well, this has been very interesting, not to mention educational. I have read almost every post on this very long discussion. I have learned many things about my hitch.

I purchased this hitch at the dealership when I bought my 2002 31' Classic in June of this year. It was the one they recommended. They installed and set it up.
It does seem to tow very nicely, or did. Lately, I've noticed more popping and groaning.

I have not weighed my axles, but the tire footprint lengths, front and rear are about the same. Tire pressures are the same. The whole rig is nice and level.

To start, I have an E2 hitch with round bars that fit up into cylindrical sections of the hitch head. On the bars there is a label that says they are 1,000 lb. bars for a 10,000 lb. GVWR trailer. My Classic has an 8,000 lb. GVWR.

When I unhitched my AS a few weeks ago, I noticed that the L brackets were loose. They will move back and forth 1/2 to 3/4 inch. The holes behind the poly lock nuts seem to be ovalized. The holes that are being used are the ones at the farthest end from the L.

My engineering senses tingled as I thought it rather dumb to bolt a lever from its farthest point.

Then I saw one of your lovely pics, it seems that my bracket is on up side down!

So, if I turn the bracket around and reinstall the L at or about the same height, I should be in the holes closest to the L. Perhaps I could fabricate a bolt and spacer to lock down the other end of the L bracket also.

As for the bending of the attachment brackets, I'm thinking spacers and extra bolt and spacer at the top end should cure that. (Grade 8 bolts are the way to go here.) If that is not enough, I would suggest welding a 3/8" X 1 to 1 1/2" bar along each side forming a C channel. (Or I could re fabricate the whole thing out of stainless steel) Yes, I have a machine shop.

Now, if any of you experts (I'm not trying to be funny here, you guys know a whole lot more than I do about this) are still available for comment, I would love to have your advice on this.
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Old 08-20-2014, 12:00 PM   #400
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Post #9 is how I got my L-bracket link plates to stay still.

30,000 miles later, they still work fine.

I have the E4, but similar concept.

http://www.airforums.com/forums/f464...ort-34484.html




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