Tires

[Fishalaska1]

Originally Posted by Bamaman

I installed 16" Bridgestone R250's immediately upon getting my trailer to the home campground.

The problem with the 17.5% G rated tires is that most fifth wheel trailers cannot handle a tire that tall. They don't have the clearance. It'd have to be a really big, heavy unit to allow such a tire.

You cannot believe how thick the tire sidewalls are on my Bridgestones. I think they weighed about 12 lbs. more each than the China Bombs that came on my trailer.

I was talking to the Costco tire dept. manager, and he's never seen a Duravis tire failure--and they're usually in extreme service F350's and F550's with service bodies and small cranes. And 16" LT/E tires are fine for the vast majority of fifth wheel trailers.

[FastEagle]

Originally Posted by Fishalaska1

Attachment 141511

You have to shop around. In this reference you will find a couple of tires sized 215/75R17.5 in LRF & LRH that are both 30.4" tall.

UR-275 | Maxxis International

[Fishalaska1]

Not much difference in heigth in a 16" 235 and a 17.5" 235

[Texastbird]

In the original size Maxxis makes a ST tire. They are working out good for me in a smaller size on my TT.

[Travelwrench]

Decided on the Maxxis same size thanks for input

[FastEagle]

Originally Posted by Fishalaska1

It is .5 inch difference in height from a 235/80R 16 to a 235/75R 17.5. Divide that by 2 since it is round and you have 1/4" taller needed for clearance.

17.5" Upgrade Information

Rethink the distance from point A to point B when measuring the outside diameter. The taller tire will be 1/2" taller in the wheelwell and 1/2" closer to a tire on an opposing axle with the same OD.

[FastEagle]

On most forums I get into trouble with the mods when I start criticizing untrue responses about replacement tire selections. Basically there is no regulation that says what size or design to use. There is no regulation that allows lowering the vehicle manufacturer's selection of Original Equipment tires. There is no regulation that says you as an owner can lower the safety standards. Unknowingly to some and anti regulatory responses by others are sometimes taken with a grain of salt.

I write a blog about tires but don't often publish it. It's unsponsored and does not violate most forum rules but, I tend to PM it to those that want to read more. I'm currently working on a multi-page research post about this subject. There are 30 - 40 research documents involved and numerous tire industry standards that have to be all tied together to complete a valid and comprehensive post.

The only valid response I have for not recommending the use of replacement tires with less load capacity than the Original Equipment tires is; It's not supported by anyone.

[Fishalaska1]

Divide that 1/2" by two. Half of it is on the bottom and half on top because it is round.

[Phill6004]

Thanks for all the wonderful input. DW and I just completed our second 30 day trip in our 2016 Crusader 321 RES, factory equipped with 235 80R 16 Tow Max tires. After three (3) tire failures in 4000 miles, I am done with cheap tires. The really great new's; no one was injured and our 5th wheel sustained only minor damage. I drive 63 MPH tops, visit CAT scales regularly, religiously check pressures, use a laser thermometer at each refueling, and I am meticulous about avoiding curb strikes. I have lost "ALL" confidence in Tow Max ST tires.....

[FaithBowls]

Why do people always think the choice is between st and lt? St means special trailer. Lt means light truck. Both designations are pretty meaningless if you ask me. What's more important is the rating, which indicates the number of plies and therefore tells you how strong the tire will be. An e rated st or e rated lt - the st will be stiffer but neither are strong enough. Go for G rated tires.

[FastEagle]

Originally Posted by Phill6004

Thanks for all the wonderful input. DW and I just completed our second 30 day trip in our 2016 Crusader 321 RES, factory equipped with 235 80R 16 Tow Max tires. After three (3) tire failures in 4000 miles, I am done with cheap tires. The really great new's; no one was injured and our 5th wheel sustained only minor damage. I drive 63 MPH tops, visit CAT scales regularly, religiously check pressures, use a laser thermometer at each refueling, and I am meticulous about avoiding curb strikes. I have lost "ALL" confidence in Tow Max ST tires.....

This is not a pro or con for your situation with tires. It's just useful information.

If your first tire failure resulted in a complete tire failure before the vehicle came to a complete stop all subsequent failures of the OE tires was predictable. The remaining tires had to carry 100% of the trailer weight. Internal damage was surely inflicted upon the tandem tire and may have transferred to the other tires as well. It's an often overlooked condition. Tire damage is cumulative and irreversible.