Concerned about tow vehicle

[telebuck]

Hi all,

We are the new happy owners of a 2012 23D serenity. But have a concern about our tow vehicle.. A 2007 Jeep Commander, 4.7l v8 with tow package. Its rated for 6500lbs, which seems ok (though maybe marginal) for our 6000lb serenity.
We had a reese straight dual cam system installed, as well as a brake controller.

So far weve taken two trips... One of about 700 miles from the dealer, and another more local 200 mile trip. so far its towed pretty well, though we did have one incident of sway where it felt like our tail was wagged abruptly back and forth as a semi was passing on the highway (also had side winds travelling northbound in NW Ohio) I applied the manual trailer brakes and it came under immediate control.

The One incident has caused me to do lot more digging regarding weights, vehicle and trailer loading, etc. One thing i didnt pay enough attention to, I fear, is the tongue weight. Was just looking at the Commander ratings and it says it can take a max tongue weight of 650lbs, whereas the serenity's hitch weight is 720lbs (unloaded).

I know i will have to take the whole rig to a weighing station to be sure, but is this a hopeless cause? Is the discrepancy between the tongue weight a total deal breaker for this tow vehicle? Or might the weight distribution hitch fix things by shifting more weight to the forward axles.

Any thoughts? I would prefer to make this setup work, but would much prefer to be safe.

Thanks!

[Nuvite-F]

Welcome to the forums, and happy Independence Day!

I agree that your tow vehicle is definitely on the marginal side for your trailer.

Fortunately you are not far from the premier integrator of big trailers and little tow vehicles, CanAm RV of London, Ontario. Can-Am RV Centre | New and Used Travel Trailers, Motorhomes and Fifth Wheels | Towing & Hitch Specialists | Top Airstream Dealer

A call to Andy Thompson and likely a trip up there will no doubt result in an improved tow rig. Or, if he thinks your tow vehicle is inadequate for your trailer, he can point you in the right direction for a better one.

Good luck!
.

[Naper]

Call Andy he will give you good honest advise.

[Wayne&Sam]

Yup, Andy.

[telebuck]

Thanks to all for the suggestion... Looks like I have a call to make tomorrow.

[ROBERT CROSS]

Doesn't matter what we think.... CanAm will soothe your soul.

You wouldn't be asking if doubts weren't creeping in.

IMHO...your tongue weight is....never mind.

ps...don't rely on published weights.


Bob

[Road Ruler]

It may just need fine tuning. Who knows? X4.... Andy

[telebuck]

I have a message in at Can-Am, looking forward to talking with them...

In the meantime, i have a bit more hard data. I took the rig to the CAT scales today, and here are the readings...

1st weighing, full rig with weight distribution:
Front axle - 2440
Rear - 3520
Trailer axles- 4440

2nd weighing, full rig but with weight distribution not engaged:
Front - 2180
Rear - 3860
Trailer - 4360

3rd weighing, just the commander
Front - 2580
Rear- 2700

Ok, so borrrowing from the calculations of another post (thank you, and apologies for not providing a full cite), here is what i think these mean.

Gross combined weight is 10400, which is under the commanders GCWR of 11,800

Tongue weight (without WD): (FA2 + RA2) - (FA3 + RA3) = 760
Tongue weight (with WD): (FA1 + RA1) - (FA3 + RA3) = 680

I am still a bit unclear about the vehicles's max tongue weight rating. The owners manual says 650, but says nothing about weight distribution. Folks on the commander owners forum seem to think this must be a non-WD rating. The hitch ball added wit the reese strait-line says it can take a tongue weight of 800lbs (corresponding to the 800lb bars).

In terms of max axle weights, the Commander has a front GAWR of 2950 and a rear GAWR of 3650. With WD i come in at 3520 on the rear, which is close but under the max.

In terms of the tongue weight as a % of the trailer weight, its 14.8 % without WD and 13.3% with WD. The 23D layout is a bit different than the others in having a higher tongue weight for the overall trailer weight.

One big caveat to the above. I did fill the fresh water tak about half full, and filled the tow vehicle with gas and camping gear, but then had a lapse of thinking,atmthe scales and forgot to jump back in before they weighed it (also missing my wife and kid). So all the above are missing about 400lbs of passengers (doh). But that shouldnt affect the tongue weight calculations much, and adding 400 to the gross combined weight i am still 1000 pounds below the max.

Anyways, sorry for being so expansive, but appreciate any thoughts from the experts.

[Friday]

Is the hitch rated for WD? You can always add some more twist to the bars to manage the tongue weight, and usually they will specify if the hitch is WD capable. WD puts some unique loads on the receiver, and if it isn't built for it you might need to get some reinforcements...

You are going to get some buffeting when big rigs go by... did it just give a wiggle, or did it start oscillating? Getting used to how your vehicle responds to the trailer is kind of scary... there is no hard rule, but generally sway is revealed more when the rear of the trailer is too heavy... the 1000lb difference in WD axle weight give you a lot of room to add more WD.

How is the attitude of the whole rig? Mostly level? Rear of TV and hitch way down? If the trailer isn't flat or a bit nose down, you are starting out bad and will have a heck of a time adjusting it.

I'm sure you can get this setup to work... maybe a bit of tweaking advice from Can-am. People are pulling your rig with station wagons...

[rodsterinfl]

Hey Telebuck congratulations on your new AS. As everyone said Andy will probably have a work-around.

I looked up the Commander specs. I would assume you have a 2007 Limited since it is the only model listed with the 4.7 Liter. You have 1200 lbs payload, a 6500 lb tow capacity and a 64 sq ft max frontal trailer rating. Your wheelbase is 109 inches with a 188" TV and a 276" AS. Your sway is due most likely to the length of the wheelbase. You would need anti-sway control and Jeep recommends it for all Class IV towing along with tow mirrors. The only issue would seem to be the extra 100lbs tongue weight and the fact that you have a max 450 lbs for people and gear in your Jeep after subtracting 750 for tongue weight. The weak point is the hitch so perhaps there are some options.

[telebuck]

Thanks Friday. The receiver is class IV from the jeep factory, and they recommend weight distribution, so i am pretty sure its capable of handling WD, but I will keep the reinforcement issue in mind.

When weight distribution is applied the rig is quite level, both the TV and Trailer.

In general when towing on the highway I usually feel a little push and then slight pull of the front of the TV toward the passing semis. But this feels very minor and completely controllable. I have only experienced one really noticeable incident as described above.. A distinct and very quick wagging of the tail of the TV (i dont know if that was the reese sway control kicking in?). Two quick tugs and then i was able to stop it with the manual brake controller. But it was enough to make me question things.

The more I look into things, the more comfortable i am feeling (learning a lot about weights, packing, etc.). Discussion with Andy at CanAm ( and visit if necessary) should do the rest of the trick.

[telebuck]

Thanks Rodsterinfl. Yes this is a 2007 Limited. The sq ft frontal area is something i had not heard of. How is that calculated... Width times height of the trailer? Roughly speaking the 23 foot would be around 76 sq ft (8 ft wide x 9.5 ft tall, including the AC).

The paylooad is also tight... Will definitely not be loading the Commander with anything heavy. It seems that the airstream would be the place for things assuming i keep from adding to tongue weight. Tongue weight seems a bit high as a percent of the trailer weight (13+%) so maybe some additional weight in the middle/rear of the trailer would be OK.

[Friday]

The dual-cam is a pretty good set up for sway control... as long as it has been adjusted correctly it should be workable. Unless there is some history of the hitch failing, Class IV and WD rating is plenty for the setup you have. Don't get too carried away with tail-loading... you can get surprising results if you start towing up a grade and the thing starts to teeter backwards... make note of where the water is migrating too as well as you go from fresh to grey/black. In my 22 it all goes from just forward of the axles to behind the axles. 30 gallons of water (or more) is a lot... you do have room to tighten the WD though.

The comment about the short wheel-base is a good one... any issue is going to be magnified the greater the difference. We bought a 2011 4Runner, never even towed with it, because it was so sketchy handling in the mountains... we traded a Tacoma on it, which worked great... ended up trading the 4Runner on a Sequoia (expensive year). My weights are close to yours for the trailer, but I have 1000lbs more vehicle. I don't use sway control or WD... have towed in crazy mountain winds, 2-way highway all the way, lots of big rigs, and it's never wiggled or waggled. I am around 500lbs on the hitch... so I don't see the point in adding 150lbs of hitch to WD 200lbs to the TV... I may add friction sway to my Airsafe, just because everyone gets so freaked out about no sway control... I dunno - I tow in ridiculous mountain terrain and it just bobs up and down behind me on the bouncy hitch... maybe I am just lucky.

If Andy gives you some pointers, let me know... like I said, I'm not way off what your setup is...

[slowmover]

Andy is the man. I hope to make that 1,700-mile trip someday to get some pointers. Nothing like an expert.

You've done a nice job with the RG formulaic chart. I'd venture that the TW question is prior to the application of WD on your Jeep . . plenty of 2-3000 lb trailers can go right over a TW restriction, and even on a 1T truck the limit is from 350-500/lbs (at the point where a WDH is required). That a WDH when properly set up is only going to leave 60-80% of TW on the RA after application (highly vehicle dependent) means a great deal. Not to mention additional TT axle weight which helps with braking the entire combination.

VPP hitch, trailer disc brakes, best brake controller: all of these enable the tow vehicle to perform as it should (when all it dialled in correctly).



Weighing #1 -- TT attached and Weight Distribution Activated

Let Front Axle Load be "FA1" 2440

Let Rear Axle Load be "RA1" 3520

Let TT Axles Load be "TT1" 4440

Then, while in same position on scales, take
Weighing #2 -- TT attached and Weight Distribution Not Activated

Let Front Axle Load be "FA2" 2180

Let Rear Axle Load be "RA2" 3860

Let TT Axles Load be "TT2" 4360

Then, drive off scales and drop TT. Return to scales and take
Weighing #3 -- TV only -- TT Not Attached

Let Front Axle Load be "FA3" 2580

Let Rear Axle Load be "RA3" 2700

From the above values, you can calculate:

TV weight = FA3 + RA3 5360

Gross Combined Weight = (FA1 + RA1 + TT1)
- should also be equal to (FA2 + RA2 + TT2) if scale weights are correct

[10,400]

TT Weight = Gross Combined Weight - TV Weight

[5040]

Tongue Weight = (FA2 + RA2) - (FA3 + RA3), or

[760]

Load Transferred to TT Axles
when WD System in Activated = TT1 - TT2

[80]

We want to see the TV FA return to the laden/unhitched value of 2,580-lbs, ideally. 180-lbs may not seem much, but as a percentage of the weight "removed" with WD unapplied, it can make more sense. And with a bit more leverage, the load on the TT axles will also increase (improve).

500-lbs of passengers will be distributed over the TV axles, but not equally.

I see no reason your combination can't be made to tow well, especially if other Commander owners are happy with the drivetrain, towing or not. Chasing details on WDH seems a pain, but you've already done much in using "the formula" with scale tickets.

Once well-adjusted, the possible variations of weights & loadings for your two vehicles will come down to a quite small range of possible hitch adjustments. Tire pressure on the TV might change a bit (rear), but the TT is always sidewall maximum.

Further, diagnosing any "maladies" with the way the combination "feels" to you is greatly simplified once weights are verified, adjustments made, etc., as they then stand out noticeably. This adds greatly to confidence . . which at 60-mph should never be taken for granted.

Welcome!!


.

[mandolindave]

I traveled from Aspen to vail one winter and saw 6 cars spun out in the median.
Five were Jeeps. It was a different situation from towing but the short wheelbase was the cause. I think that the trailer would move the TV around when turning, braking, and a variety of situations. I would never WANT to tow with any SUV, other than the Suburban.

[Friday]

Originally Posted by mandolindave

I traveled from Aspen to vail one winter and saw 6 cars spun out in the median.
Five were Jeeps. It was a different situation from towing but the short wheelbase was the cause. I think that the trailer would move the TV around when turning, braking, and a variety of situations. I would never WANT to tow with any SUV, other than the Suburban.

Jeeps tend to come with large tread-block tires that look like they'd be great in the snow, but fail miserably on the ice... add in the 'wider than they are long' factor, and you've off to the cabbage patch...