Effects on towing with larger diameter tires

[TWX]

On my Jayco Jayflight SLX7 174BH Baja I'm considering replacing my stock 15" wheels and 215/75/15 tires with 17" wheels and 255/75/17 tires that will match what's on the tow vehicle. Principal reason is to allow for sharing of spares between tow vehicle and trailer, and secondarily for increased ground clearance.



The difference in tire diameter would be 4.4", which means a 2.2" lift.


I am reasonably certain that the tires will clear the wheel wells on the factory Baja-lifted trailer. I'm interested in thoughts on the effects of crosswinds and general handling with this change. the sidewall height change is not as substantial due to the wheel change, but isn't ignorable either.


I've already contacted lippert regarding brake drums and wheel mounting pattern, there's a 6 on 5.5" brake drum with the same spindle dimensions as the 5 on 4.5" drum currently equipped. The bigger bolt pattern is ostensibly for a 4400# axle, but from what I gathered in corresponding with Lippert, the dimensions on the spindle are the same amd it sounded like when they make axles, the higher-rated axle still uses the bulk of the same parts as mine, so using this drum should be no problem.

[Jagiven]

Bad news cannot run P rated tires on a trailer, and cannot run. ST tires on a TV. LTs on the other hand can swap back and forth with the right load derating.

I have ran LTs in the past and they preformed very well.

When I looked at up sizing tires on a tt, I called the frame manufacture. They informed me how much clearance was required between each tire and the wheel well.

Good luck.

[TWX]

Originally Posted by Jagiven

Bad news cannot run P rated tires on a trailer, and cannot run. ST tires on a TV. LTs on the other hand can swap back and forth with the right load derating.

I have ran LTs in the past and they preformed very well.

When I looked at up sizing tires on a tt, I called the frame manufacture. They informed me how much clearance was required between each tire and the wheel well.

Good luck.

Yeah, trailer is going to have LTs regardless. I'm more concerned about tire size than I am concerned about tire brand, since if I'm at the point where I need a second or third spare I'm just trying to get out of there.


Very likely I'll run steel wheels on the ground for greater durability but my spares will probably be on lighter aluminum wheels to reduce weight.

[Jagiven]

We use to have a guy named Greeny?? He was a transporter towing mostly Jaycos at the beginning. He said trailers with aluminum rims towed better than those with steel rims. FYI, trailer rims are designed differently than vehicle rims. I know you cannot run standard TV rims on a trailer. Not sure about the otherway around.

We upsized wheels on a Nomad switched to LTs on steel rims. Used a different design equalizer between axles that gave more lift. I think it caused a 2-3" overall lift. Pulled great. I suspect we had to adjust the WDH.

[TWX]

Originally Posted by Jagiven

We use to have a guy named Greeny?? He was a transporter towing mostly Jaycos at the beginning. He said trailers with aluminum rims towed better than those with steel rims. FYI, trailer rims are designed differently than vehicle rims. I know you cannot run standard TV rims on a trailer. Not sure about the otherway around.

We upsized wheels on a Nomad switched to LTs on steel rims. Used a different design equalizer between axles that gave more lift. I think it caused a 2-3" overall lift. Pulled great. I suspect we had to adjust the WDH.

As far as I can tell the principal difference is wheel offset. I have a plan to deal with that.

[Flyrotor]

I for one think running LT’s on a trailer works great if you have the right setup

[TWX]

Hmmm. Weirdly in the the tire size I use, the SL-rated tires actually have higher load ratings than the LT-rated tires. Like, 200-300# more.


SL-rated Load Index is "115" or 2721#.