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jkcru · 09-22-2008, 07:56 AM

I would consider switching to the single wheel and tire system that replaces the dual wheels with a wider softer single.

Bluto · 09-22-2008, 10:45 AM

Vinnie,
My TV is a Chevy diesel, crew cab, long bed dually. When my truck is empty I run the tires at 60 front and 45 rear. My trailer is a lot lighter than yours but here's what I do when towing my 23'. Front 65 psi and rear 55. When I hook up my equipment trailer with skidloader and attachments on board I have the rear tires at 70-75 and front at 65 psi. There are tables available from tire manufactures and dealers that address the issue of tire pressures vs weight on them. I can't locate it but maybe someone can post that for you. Another thing I do is look at the foot print of the tread to the road surface. I take some chalk and mark my tire across the tread about two inches wide, Drive my truck a short distance and look at those marks I made on the tires. I do this as a guage to see if I'm over inflated. If it's way over inflated for the load you are carrying then the more of the chalk will remain near the edge. Under inflated and it will all be gone on the edge. I like to see some chalk on the edge after the drive but not much. Using both the chart and the chalk is how I came up with the best inflation and ride for my tow vehicle.
Now there is a product out called Sulistic shackles that are suppose to help provide a smooth ride on an empty HD truck. But, they also raise the aft end about an inch and a half when installed. My truck is high in the back now and I don't want to do add to that.
As far as air bags go, the Firestone's are to help your springs cope with more load and do not soften the ride. I have had the air bags on my old Ford but it did not make the ride softer. Most of the time I ended up with very little air in them because the more you add the stiffer the ride. I only used them when I overloaded the bed with wet
sand or dirt that was super heavy. You may be wasting your money on that type of air helper spring. As far as I am concerned, I think the dually truck is the best stable platform you can buy to tow with and once you adjust your Reese system and air pressures of your tires to match your load you will never look back. By the way, I have the Reese system and my trailer follows my truck threw turns as if it was on rails. Good luck, and enjoy your truck.

crispyboy · 09-22-2008, 10:58 AM

If you were adding airbags to the rear of the truck - then why wouldn't you get rid of a few leaf springs? Pump up the airbags when your going to haul a lot of weight.
I have no experience with this system just my assumptions.

SteveH · 09-22-2008, 12:19 PM

Quote:

Originally Posted by Inland RV Center, In

How many miles a person may tow, has nothing to do with Physics.

When weight is added to the back end of the dually, some weight then is removed from the front end.

Now if you have a Peterbilt, then that's a different story.

We all know, or should know, that when you reduce the weight on the front end of a tow vehicle, huge trucks excepted, that the steering to some degree has been compromised.

Sometimes it takes years for that persons day to come, but Physics says it will.

Is it his luck, or his poor decisions that haven't caught up with him?

When you settle a claim, as I have, with a family, that had it's parents killed in a rollover, because they used that "magic truck", then perhaps you may feel differently than I.

Andy

Andy,

Again, you are right. Physics don't change, and everyone knows the physics of a one ton dually truck are quite a bit different from the average family sedan, which most of the weight distribution hitches were originally designed to work with.

I know we have "discussed" this before, and here we go again....a sedan, or even an SUV, is designed to carry it's load in the middle of the vehicle between the axles, where as a truck is designed to carry it's load over the rear axle. No "magic truck", just a different designed vehicle from the frame thru the suspension, and to include the body.

Ford built a pickup in 1962, I believe it was, that had the body and bed built together as one piece like a sedan. It was a complete failure and they reverted back to the split cab and bed the next year. That was because trucks are different and loaded/used differently than sedans, and the one piece, sedan type body just did not work well on a truck.

A large trailer with a heavy tongue being pulled by a sedan without a WD hitch, I'll agree, is a disaster looking for a place to happen. However, trucks pull large heavy trailer withour WD hitches all day long, every day of the year, and there are rarely problems caused by the lack of WD hitches.

I'm not advocating that one should get out on the highway with a half ton truck towing a 34 footer without a WD hitch, but a one ton dually is not anything like a 1/2 ton, save the cab. And, I'm not even saying that one should do it, but what I'm saying is, it is done daily without incident.

Diesel1 · 09-22-2008, 12:29 PM

Quote:

Originally Posted by vlamica

Diesel1.. are you afraid that the low tire pressure will heat up those tires to temps that might cause a blowout? The tongue weight on my airstream is upwards of 1200 lbs. The truck is heavy too.. i usually run 65psi in all tires as they will heat up to about 70+.

Thanks Vinnie

1200 lbs sounds like a lot of tongue weight to me, is your trailer 12,000 lbs? the tongue weight should be 10-12% of total trailer weight. At the Ford Arizona Proving grounds we did duribility testing on Ford pickups. All trailer towing was done at max GVW & we used equilizer hitches. But we did not exceed 12% of the trailer weight on the tongue.10% was what we wanted. We weighed trailer, then just the tongue , and ajusted the load till we got 10% on the tongue. If you get your tongue weight right you will not be able to overcome the laws of physics and raise that 925 lb powerstoke up in the air. Unless you have a 12,000 lb Airstream.

Airslide · 09-22-2008, 03:28 PM

Hello Diesel1,

Yes.. she is a heavy girl. The slideout adds considerable weight. I was surprised as I originally thought it would be something like 800lbs but its actually upwards of 1200. The trailer has a loaded max weight of around 9200 lbs. So its not 12k lbs but feels like it when your towing. I understand your testing. I actually worked for Volvo and spent some time at APG out in Wickenburg. We put the cars through all kinds of tests towing. This truck is also heavy and long. Not only is it the diesel motor but its a crewcab. It would take some very bad things going on to get the front end of that truck up in the air. I just want to be safe, not damage all those rivets on the trailer and have trouble free towing. Maybe a few less leafs and 500lb bars? Not sure. I will have it weighed to be sure where all the weight is.

Thanks Vinnie

Diesel1 · 09-22-2008, 05:47 PM

That interesting, I worked at VAPG for the first three months of 2006. We were slow here and I got sent there.
At VAPG we were working on ride quailty for the 2008 Super duty, which is much improved over the trucks you or I have. That was accomplished in part with longer springs. Also the spring leaf varried in thickness from the end to the middle. I don't think you will accomplish much in the way of ride quilty by removing spring leaves. I think to get much noticably difference you would need new spring packs. The old F350 are just rough or choppy compared to new trucks.

Mikethefixit · 09-22-2008, 06:10 PM

vlamcia
Before ya go all crazy on us,and lose the leaves out of the springs. Try the bars first. I would leave the tire pressure at 80 psi or what ever is on the sidewall of the tire. Next I would see how much weight U are transferring. You may have the chains way to tight. I have 7 links in my chains are I and using the very last one. If I go up one the ride gets so choppy you can't stay in the seat. I am think this so called dealer didn't have a clue as to how to set up this hitch. They just threw it together and sent ya down the road.
So do the little things first before ya start tearin down the truck and replacein things ya don't need.
Let us know We are Waiting,LOL
Roger

Cracker · 09-22-2008, 07:02 PM

Quote:

Originally Posted by Dooley

Vinnie,

My TV is a Chevy diesel, crew cab, long bed dually. When my truck is empty I run the tires at 60 front and 45 rear. My trailer is a lot lighter than yours but here's what I do when towing my 23'. Front 65 psi and rear 55. When I hook up my equipment trailer with skidloader and attachments on board I have the rear tires at 70-75 and front at 65 psi. There are tables available from tire manufactures and dealers that address the issue of tire pressures vs weight on them. I can't locate it but maybe someone can post that for you. Another thing I do is look at the foot print of the tread to the road surface. I take some chalk and mark my tire across the tread about two inches wide, Drive my truck a short distance and look at those marks I made on the tires. I do this as a guage to see if I'm over inflated. If it's way over inflated for the load you are carrying then the more of the chalk will remain near the edge. Under inflated and it will all be gone on the edge. I like to see some chalk on the edge after the drive but not much. Using both the chart and the chalk is how I came up with the best inflation and ride for my tow vehicle.
Now there is a product out called Sulistic shackles that are suppose to help provide a smooth ride on an empty HD truck. But, they also raise the aft end about an inch and a half when installed. My truck is high in the back now and I don't want to do add to that.
As far as air bags go, the Firestone's are to help your springs cope with more load and do not soften the ride. I have had the air bags on my old Ford but it did not make the ride softer. Most of the time I ended up with very little air in them because the more you add the stiffer the ride. I only used them when I overloaded the bed with wet
sand or dirt that was super heavy. You may be wasting your money on that type of air helper spring. As far as I am concerned, I think the dually truck is the best stable platform you can buy to tow with and once you adjust your Reese system and air pressures of your tires to match your load you will never look back. By the way, I have the Reese system and my trailer follows my truck threw turns as if it was on rails. Good luck, and enjoy your truck.

I couldn't agree more and I have so stated on the forums in the past - although I do run about 65 front and 50 rear when light - then go to 55 rear when towing. The only difference is that my dually is dedicated to either towing the Airstream or travelling unloaded as our long-trip Cadillac. With that in mind, I changed the rear springs to an alternate GM spring set that is roughly equivalent to a 2500 series spring set - which also served to lower the rear end about 4 inches or so. I use 1,000 lb equalizer bars with a Reese hitch, for a measured (Sherline) hitch weight of 940 lbs, however I load the bars somewhat lightly. The weight reduction on the front axle - when loaded - is around 200 lbs or so before tensioning the bars and it doesn't change appreciably with the bars tensioned. With that heavy Duramax diesel, 4wd, A/C, and retrofitted Goodyear steering axle tires, I'm still carrying over 4,400 lbs on the front axle - which is only about 400 lbs below maximum. Don't take me to task for the exact numbers - but I can assure you I'm close, based on actual scale weights. The only comment I would make with reference to some of the earlier responses is that Goodyear does not recommend pressures below 45 psi - and that tidbit of information is in their inflation charts. I love the stability and the associated ride and handling - even as I endure my wife's looks of irritation on bumpy roads - and, check as I may, after five years of towing I haven't found a single loose rivet.

Airslide · 09-22-2008, 08:37 PM

Roger,

So when i saw my rig pull up at the dealer service dept and things were all said and done the service advisor told me that she is all set to go. The first thing i noticed was the back of my truck was sitting like it does when its empty and the front of the trailer is raked upwards. I just wanted to get out of there and asked the guy as he did a quick walkaround what links i should keep it on and he told me as he pointed to the third link from the end.. "this one" and if it settles go one more! LOL.. what a dork. Like i said i just wanted to get out of there. I towed it from Gilroy through the bay area up north. The steering of the truck was noticeably heavier and im sure the rear tires of the trailer were busy carrying the weight of the truck. I will get it weighed and then consider the one link option (if any)..

Thanks Vinnie

Mikethefixit · 09-25-2008, 08:22 PM

Hey VINNIE
I'm sorry I had to look for your reply, I've been busy and had not had time to reply and the thread disappeared. Yes defineatly weight that outfit.Sounds like to much wieght is going on the steering. That outfit should be almost perfectly level. Just as a quick check when hooked up, lay a 2 ft or what ever box level fits in the threshold of the door. Open door lay the level parrell in the doorway or on top of the fridge.
I'm a retired trucker (owner-Operator) <<< that means I paid the bills. I hauled steel and meat(not at the same time of course) So I know how to balance loads and transfer wieght.
It just sounded to me like and adjustment problem that can be taken care of wiff a little experiminting. That truck likes heavy loads so just get the steering and drive close to each other by weighing and tweekin on the hitch. The trailer is what it is.
Let me know how it comes out.
Roger
PS I attempted to attach a recent photo but its the wrong size I think.

Airslide · 09-25-2008, 09:00 PM

So Mike, with your experience, do you even think i need to run the bars at all? When i hitch the truck up to the trailer and adjust the hitch bolt to the proper height the truck now sits perfectly level and so does the trailer without the bars.. If thats the case even with 60 lbs in the tires what am i using the bars for? Just to say i have them so im safer? It seems like this truck could care less about the load bars even with the 1200 lb tongue weight?

SteveH · 09-26-2008, 05:56 AM

Quote:

If thats the case even with 60 lbs in the tires what am i using the bars for? Just to say i have them so im safer? It seems like this truck could care less about the load bars even with the 1200 lb tongue weight?

vlamica,

The bars on a weight distributing hitch move the trailer tongue weight foward on the tow vehicle eliminating the tendancy for the tongue weight on the bumper from lifting the front axle, or reducing the weight on the front axle of the tow vehicle. It's probably not mandatory with a truck the size and weight of yours, but it will help. Any time you reduce the weight on the front axle, a possibility of loss of stearing exists. It's not an issue in static condition, and may not be an issue driving down a flat road, but if there are irregularities in the road surface, the varying weight on the bumper from the trailer tongue weight, will vary the weight on the front axle of the tow vehicle, and presents the possiblity of loss of control.

Bluto · 09-26-2008, 07:58 AM

Quote:

Originally Posted by SteveH

vlamica,

The bars on a weight distributing hitch move the trailer tongue weight foward on the tow vehicle eliminating the tendancy for the tongue weight on the bumper from lifting the front axle, or reducing the weight on the front axle of the tow vehicle. It's probably not mandatory with a truck the size and weight of yours, but it will help. Any time you reduce the weight on the front axle, a possibility of loss of stearing exists. It's not an issue in static condition, and may not be an issue driving down a flat road, but if there are irregularities in the road surface, the varying weight on the bumper from the trailer tongue weight, will vary the weight on the front axle of the tow vehicle, and presents the possiblity of loss of control.

Steve,
I agree with you, and in addition the other problem that will be seen when the load on the front end is changed is the wear on the front tires. When you lighten the front end too much by loading up the receiver, the tread wear will start to show odd scalping spots along the outside edges of the front tires.

SteveH · 09-26-2008, 09:30 AM

Quote:

Originally Posted by Dooley

Steve,
I agree with you, and in addition the other problem that will be seen when the load on the front end is changed is the wear on the front tires. When you lighten the front end too much by loading up the receiver, the tread wear will start to show odd scalping spots along the outside edges of the front tires.

Yes, and the reverse, with most independent front suspension vehicles, when you load the front too much with the WD hitch, you will start to see the scaloping (cupping) on the inside edge of the tires.

mandolindave · 09-26-2008, 10:11 AM

Quote:

Originally Posted by overlander63

The heat in the tire that leads to a blowout is caused by flexing of the sidewall, either from underinflation, or overloading. A standard one ton truck is designed to haul a minimum of 2000 pounds in the bed, and usually more than that, with only two tires in the back. That means each tire on a duallie will be carrying about 500 pounds of cargo at 80 psi. As far as the load, you shouldn't have a problem. Now, a secret: Reduce the tire pressure to about 50, hook up the trailer, and drive it around for a few miles, then crawl under the truck and look at the space between the dual wheels. If along the widest part of the tires, you see rub marks on both tires, they are touching each other under load. Add some more air and repeat your drive.

A friend of mine was advised to increased the PSI of his toy hauler tires,
so as to increase his MPG. After blowing out two tires, he went back to manufacters specs. SO, can over inflating lead to the overheating of tires as well ???

Airslide · 09-26-2008, 10:12 AM

I agree with you guys. I still plan to get everything weighed and get the real story.

Cracker · 09-28-2008, 01:05 PM

One additional problem with the GMC Dually - at least the 2003 model - is that the front tires have a problem with "scalping" on the outside edges - loaded or not. I went through two sets of tires before switching to a Goodyear "steering axle tread design" tire that came out early in 2007. These tires weigh almost double that of a standard tire and, like the tires for over-the-road rigs, they can be re-grooved when the tread wears down. The cost reflects that capability, but after running them for over a year I haven't seen any signs of unusual wear. Essentially the tire tread has very heavy shoulders - with no sipes (i.e. - "cross-cuts') - while the remaining tread consists of simple deep parallel grooves about an inch or so apart. I believe the cost was around $245.00 each. My driving with this rig used to consist of roughly 30% towing and 70% bobtail - most all of which was highway. With the cost of fuel being so ridiculous, it's become more of a dedicated towing rig - while we use the "baby" vehicles for long trips.

Airslide · 09-28-2008, 07:48 PM

Those are good points. with the independant front suspension this truck is running i would imagine you will get some bounce causing repeated negative/positive camber just by design. When i lift the truck with a floor jack the angles get seriously positive really quick. The bars will help with that for sure. The tires you mention are interesting. Im running the Toyo "open country" tires. They are $175.00 a piece anyways for what i see as being a standard truck tire. I was trying to keep them all matching and thats whats on the back but the fronts are getting close to replacement time.

Vinnie

Cracker · 09-29-2008, 05:14 PM

I stopped rotating the tires some time back due to the weird wear patterns I was experiencing on the front tires. They created too much of a mis-match with the duals. Subsequently, the rear duals are still in excellent condition - with over 60,000 miles on them. That said, I now consider the front tires to be totally independent of the rear duals with respect to design. Thus the dedicated "steering axle" tire.