Short Bed Ext. Cab vs Long Bed Four Door

[svt440]

Hey everyone. I have a 30' fifth wheel that weighs in around 8400lbs dry. Currently towing it with a 2003 2500HD Silverado Duramax. Truck is an extended cab, short bed (the shortest truck you can get aside from a two door short bed). I felt it get a little squirmy a few times at 65mph that made me nervous enough to back off the gas. Did it a couple times in a couple of hours. One thought I've had, is buying a newer four door, long bed, 3500 srw. My thoughts are, with the longer wheel base and the heavier suspension, I will be over trucked (at least for an 8500-9000lb setup) and not feel like I'm the minor like I do in my current truck. I know a dually would most likely eliminate that possibility all together (I see these things with the hammer down running 70+mph on the freeway with tri-axle fifth wheels!) but I'm really preferring a srw and given the fact that I have a lighter fifth wheel, I feel like a 3500 srw should be more than enough truck.

Question is, will I notice much difference between the combination of a greater wheel base, and the heavier suspension, or will it not change much? I know the HD series trucks are similar to a 1 ton, (or so I read), so I'm wondering if my only gain in this situation will be the longer wheel base. Any thoughts or experience? <- preferred! Thanks guys!

[cmeade]

Old-Biscuit wrote:
I have a 3500 QC Longbed SRW and tow a 14K 5th wheel.

Great combo/set up.

You would do well with a 3500 SRW as tow vehicle.

Yes the 3500 suspension is heavier and non-towing it rides like a truck cause it is a truck.
Loaded up/towing.......smooth relaxing stable oh yeah!

X2 except we have a megacab, B&W, and Bilstein 4600 shocks.

[Old-Biscuit]

I have a 3500 QC Longbed SRW and tow a 14K 5th wheel.

Great combo/set up.

You would do well with a 3500 SRW as tow vehicle.

Yes the 3500 suspension is heavier and non-towing it rides like a truck cause it is a truck.
Loaded up/towing.......smooth relaxing stable oh yeah!

[Bedlam]

If you are getting squirm while towing, there is something wrong with your hitch setup. Going to a longer wheelbase may mask the problem, but not address the cause. My F250 extended cab short bed diesel was very stable towing a tall bumper pull toy hauler weighing 11K+ lbs. I used a 1200 lb L-bar WDH with one friction anti-sway device and kept my towing speed at or bellow 65 mph due to tires and most of the locations I towed.

I would look at the following:
1. Actual pin weight verses actual loaded trailer weight
2. Verify your tow vehicle is leveled under load with sufficient front axle weight
3. Verify the trailer is level or slightly nose down when hitched
4. Run your rear trucks tires at maximum PSI
5. Allow your overloads to take some of the load if you use air bags for leveling