How much does truck length affect towing stability?

[Fallon]

I've looked at the charts for capacity occasionally. Pretty much all the diesel option will fit my capacity needs. I'm mostly looking for people's experience on how smooth & stable the various length options are while doing it.

My current F250 has the utility box on it because that's what was on it when I found the deal. I use the storage because it's there, but I'm not planning on getting another utility bed. If anything other than a regular bed, I'd go with a flat bed. Easier to access stuff on a flat bed without climbing in & easier to toss a spare impliment on with just forks. It's a pain to rig up an impliment with chains to get it in it or out when there is a trailer blocking the back.

Pretty stuck on a 3/4 ton SWD. They stay under the 26,000 CDL limits that the 1 tons don't. No need for the extra wheels to maintain either.

I do as agree on the air ride too, given the varying loads it will be hauling, or not. I expect I'll be looking at grampas old RV hauler with a higher trim level anyways. Assuming it will end up being another F250 as Ford has most of the market share here in CO & I'm looking slightly used. Not opposed to a Chevy if the right one turns up. For some irrational reason I dont like Doge though. Never have really figured out why & I've never owned one.

 

[nikerret]

A single wheel 3500/F-350 would ensure you have the better pulling truck, especially, if you’re thinking flatbed. Also, at that light weight, you don’t need a diesel. The current gas offerings are great. I have a 2014 F-350 dually flatbed with the 6.2L gas. Regularly pulling 10K to 15K, sometimes more. Flatbed is nice. Gas gives you much more payload to use that flatbed.

A 2500/F-250 would be fine, you won’t notice enough to matter on length. Again, you’re not pulling that heavy. Having enough trailer to move your load where it needs to be on the deck is more important than a longer truck.

 

[zzvyb6]

Well, I AM ex expert on towing from an engineering and experience standpoint. I worked 40 years in all aspects of Vehicle Dynamics. So the answer to you question is simple and I will add some additional advice.

1) Wheelbase: Longer is better.

2) What is more important though, is distance from tow hitch to rear axle. Shorter is better. Negative is even better (That's why a 5th wheel hitch is so much better than any other form of towing). This is because as the towing vehicle turns, the hitch point moves laterally in a direction opposite from what the steady state position will be. Hence, this produces a tendency to oscillate or 'overshoot'. As speed increases, the stabilizing effects of wheelbase diminish too, leading to the tendency to sway and even jackknife.

3) Nothing beats a GOOD set of tires properly aired up. Not bargain tire constructions, they don't have the lateral stiffness required to keep the truck and trailer on the desired path. There are special trailer tires made with VERY high sidewall stiffness, bruise resistance, and storage (aging) resistance.

4) Truck tires on the tow vehicle always have a Catch 22" They need 80 psi (for example) to carry the axle and hitch load, but they have the highest lateral stiffness (sideslip restraint) at about 50 psi. But, at 50 psi, they may overheat from sidewall flexing and separate the tread from the carcass.

5) A tow vehicle with dual rear tires on each side is the safest condition because now the tires can be run at 50 psi with each of the 4 tires carrying only 1/2 the load compared with a single tire equipped axle would have.

6) A dual or triple axle trailer is safer because A) the load per tire is less and B) the trailer axle separation distance(s) introduces a yaw angle and yaw velocity twisting resistance (scrub), which is a big stabilizing factor.

7) Vehicles I've worked on for towing capability, work best with 'frame level' operation. This means keep the truck frame level (horizontal) as well as the trailer frame.

8) Air shocks for load leveling are not always the best way to go because: The towing vehicles suspension is designed to droop a bit when payload is added and the suspension geometry is altered to increase stability. That's why a truck usually looks a bit high in the back. When loaded, it should be level for best stability and driveability. Also, the level control shocks or airbags increase the rear roll stiffness, which shifts the combination's stability margin in a (bad) rearward direction.

That's the Expert opinion, I'm pretty sure some 'others' may contest some of this, but this is what you will hear from me in Court in case you wreck and don't want to accept the blame.

 

[RustyA]

F-350 will have one more leaf in rear springs and overloads are standard. Be sure to add camper pkg so you get the rear sway bar, it can make a difference in the wind or heavy loads on uneven surfaces. My 2011 350 Crew 4X4 shortbox spent the weekend pulling a 22 ft deckover 14K trailer all weekend hauling large round bales. I figure it was 15-17K total weight and my 6.2 gas just purred along...6 speed auto with engine braking in tow/haul really pulls stuff nice.

 

[dstig1]

Only thing I will add is that the most popular configuration for F250/350s is crew cab (4 door) and short bed - by far. That seems to be what everyone is buying so if you want the long bed, you will have to work for it. I wanted the supercab/long bed to keep the length down also, and it took months to find that, especially since i did not want diesel. Buying new would probably be easier to get what you want if it isn't that config, but used is tough.

 

[4570Man]

Getting rid of the bumper pull trailer is the best thing you could do for stability. A gas truck will be fine for limited towing. A diesel will definitely get better mpg but it doesn’t sound like you’re towing enough to matter. Despite what the GVW says a 3500 dually is a huge step up from a 3500 SRW. I’ll put twice as much on my ton dually as a SRW truck will handle. Or you could take the ridiculous overkill approach. Really I bought that with a different idea in mind. My trailer out weighs that load.

 

[HCJtractor]

I switched from an 06 F350 crew cab longbed to a 08 F250 extended cab shortbed, both diesel. And I pull a bigger tractor than yours with a deck over goose neck. I really can’t tell that much difference pulling or handling. But my newer one sure is easier to drive and park without the trailer. But the shorter wheelbase seems a little more “choppy” when hitting road bumps, but that’s not a big deal. And I do miss the bigger back seat to stash stuff. Frankly, I don’t think it really matters which you pull with.

 

[nikerret]

Also, get the pulling gears; ie, 4.30 vs 3.73 (Ford gas), if towing is important. It makes a huge difference.

 

[Renze]

. Also, the level control shocks or airbags increase the rear roll stiffness, which shifts the combination's stability margin in a (bad) rearward direction.

Look, i dont claim to be an expert on vehicle dynamics, but i did design trailers, convert vehicles, and help design testbenches for air suspension trailing arms do ive seen a few things: Your statement is theoretically correct, but is a wild exaggeration when applied to the subject discussed.

That's the Expert opinion, I'm pretty sure some 'others' may contest some of this, but this is what you will hear from me in Court in case you wreck and don't want to accept the blame.

On the internet, everybody is an expert. Who cares

 

[EddieWalker]

In my personal experience, duel rear tires make the biggest difference that I've experienced. It's like the rear end of the truck and the trailer are locked into the road. You just feel the difference, and it's significant.