upgraded from 14" GYM to 15" LT

[tvoneicken]

Today I finally completed an upgrade from the dreaded 14" Goodyear Marathons to 15" LT tires. I have the 5 bolt 4.5" lug pattern which made 16" wheels impractical without changing the hubs, which was more than I wanted to bite off. Also, my tire guy says that 16" tires wouldn't have fit, but I didn't investigate that too closely.

What I got are 5x Sendel Mod 15x6 5-4.5 wheels from tredit.com shipped to my local tire shop for ~$540 and 5x Yokohama Geolandar LT235/75R15 load range C tires for ~$920 mounted and all.

The tires fit well, but are pretty tight at the very front of the wheel well (~1.5" space left). For the spare we had to bend the vertical retaining brackets a little bit, but it does fit well. I gained about 1 inch in clearance under the trailer, which I'm really happy about. I had to adjust the hitch to keep the trailer level.

Overall I'm very happy with the outcome, we'll see how it all handles and lasts... I'm attaching a bunch of pix. The first one shows the difference in tire size, two more show before/after 14" vs. 15", and the last one shows the clearance at the tire front.

[Ridgerunner3]

This gives me a 15" LT tire option that I did not know existed. Please keep us posted on how they perform.

[GregU]

I am looking to do the same thing with my 23' 2008 CCD International. The front tire clearance worried me as well. Airstream told me it probable could not be done without a new axle and to take my AS to the dealer. The dealer told me he had never done this and to call AS. Thank you for your posting and please let us know how it works out.

[tvoneicken]

I'm heading to the grand canyon at the end of this week, approx 600-700 miles, so I can report whether I make it there ;-) and whether I feel any difference...

[GregU]

I may delay my Oct 9 appointment to have my Airstream worked on until you get back with your report. I noticed you went to Yoko Geolander LT235 instead of LT215 like the GYM OEM. Was this for the extra load capacity? How close is the new tire to the side of the fender. I now have about 2" of side clearence and the wider wheels and tires will probably take up some of that. Also did you buy the H/T-S (GO51) Yokos?
I just finished a 5500 mile tow on four Goodyear Marathons. When I pulled into my driveway, I noticed that I had major separation in two of the four tires but no air loss. The steel belts were exposed on both tires. They were original 2008 GYMS. I also have a utility trailer that spends most of its life in a garage. I have GYM's on it also with 1000 miles on them. I pulled it out to check those tires and I was astonished to find two of the four GY Marathons also had broken belts from just sitting. I guess I must be the luckiest guy around to have four GYM go bad without a single blow out. Like you, I am very careful about my tires. I measure pressure every day or so when on a trip and have weighed my fully loaded 23' CCD trailer and tow vehicle to insure that I am nowhere close to overloading. I guess you will have to count me in as having the opinion that the GYM tires are junk. I ran LT tires on the utility trailer for 15 years without a single tire separation.
Thanks in advance for keeping us informed on your tire upgrade.

[BAB]

Met a fellow A/S on the way back from a 3000 mi trip a week ago. He and his wife had bought an incredibly (almost) new 10 yo Classic. Very carefully maintained. When I met them, they'd just had a "catastrophic" failure of one of their GYM's (wheel well damage) from steel belt. We had a long conversation about going up one wheel size so he could go to the LT tires. He was surprised that I'd pulled the wheels off my brand new 2012 Intl to go with the bigger wheels and the Michelin's. Based on our conversation, he was pretty much convinced that he needed to follow the example of a bunch of us with concerns RE: GYMs. End of story. Had an email from him late last week. AFTER we had our dinner/conversation they headed home. Had a SECOND catastrophic failure of another tire. Then....only 4 miles from home....had a THIRD catastrophic failure of another tire. So, that's 3 out of 4 tires. Wondering if he may have something else (like out of alignment situation?), but he's had more than enough. Could also be a case of what looked like really good rubber but had some rot happening. I'm delighted with my decision to upgrade. Over a 3,000 mile haul -- I had ZERO issues with tires. Watched the pressure (I installed monitors when I upgraded), checked appearance, banged sidewalls, etc. At times, I was pushed to hit 75 (left lane trying to move over)....tires look and feel perfect. Best of all is a reduction in "nervous driver syndrome"...

[tvoneicken]

GregU: if I were you I wouldn't wait. I went for LT235 over LT215 for a couple of non-scientific reasons. I saw that others gravitated to that, I wanted a little extra ground clearance, and "bigger is better". So I started asking whether I could get LT235 to work and never looked too much into LT215. I ended up sending the tire guy a list of possible tires and he recommended the Geolandar.

I went to an independent tire shop where I got good service. Had the wheels shipped there by tredit. The tire guy first mounted one tire and fit it onto the AS. We put a block under the tire and dropped the AS onto it so that tire carried the load and verified that there still was quite some space all around. Only after that did he mount the other 4 tires. If the first one hadn't fit it would have been relatively easy to repackage everything and ship back (or find a different tire for the same wheels).

At this point I've only driven 12 miles, but they include highway and 1-lane winding mountain road, plus turn-around in the driveway. No issues I can see so far and I don't expect much new on our trip. The next question really is about longevity/wear and that'll take a while to find out.

And yes, they're H/T-S, you can see that in the second photo, actually. I'll get the side clearance for you tonight...

[jcanavera]

Originally Posted by BAB

Met a fellow A/S on the way back from a 3000 mi trip a week ago. He and his wife had bought an incredibly (almost) new 10 yo Classic. Very carefully maintained. Wondering if he may have something else (like out of alignment situation?), but he's had more than enough. Could also be a case of what looked like really good rubber but had some rot happening. I'm delighted with my decision to upgrade. .

I would have loved to see the age of those tires. If they were the originals, then there is no doubt why those things let go. As most of us know, you can't trust the "look". If you are buying used, you need to look at that manufacture date on that tire. Too bad he learned that lesson the hard way.

Jack

[Skater]

Originally Posted by BAB

AFTER we had our dinner/conversation they headed home. Had a SECOND catastrophic failure of another tire. Then....only 4 miles from home....had a THIRD catastrophic failure of another tire. So, that's 3 out of 4 tires. Wondering if he may have something else (like out of alignment situation?), but he's had more than enough.

In addition to the comment jcanavera made about tire age, there's another factor at work here - when you blow one tire, the camper's weight is now on the remaining 3 tires, so they get stressed even further.

[tvoneicken]

Ok, update on the LT235/75R15 Yokos. I'm not sure I'd recommend them. So far I've driven ~600 miles from CA to the grand canyon. The rig feels more prone to sway and I suspect the tires. I've changed too many variables to be able to tell for sure: new TV tires, new TT tires, 1" higher TT, adjustments to the hitch to accommodate higher TT...

What I feel is that when a semi passes me the TT gets pushed over more resulting in me getting closer to the truck and requiring a bigger steering correction. I have a hard time believing that 1" in height causes this and suspect that it's the tires that are softer. I'm currently a couple PSI below max inflation and I'll pump them up to a few PSI above max for the way back to see whether that helps.

Live and learn... but if you're looking for R15 tires, you may want to check for something stiffer than the Yokos. Although, of course, I may be completely wrong in my diagnosis... Is there any metric for sidewall or tire stiffness I might be able to look up?

[mstephens]

Quite as number of people changed from GYM to MICHELIN LTX in the past year. I know I am very happy with mine. What tipped you over to try the Yoko instead of the Michelin?

[r carl]

Originally Posted by tvoneicken

Ok, update on the LT235/75R15 Yokos. I'm not sure I'd recommend them. So far I've driven ~600 miles from CA to the grand canyon. The rig feels more prone to sway and I suspect the tires. I've changed too many variables to be able to tell for sure: new TV tires, new TT tires, 1" higher TT, adjustments to the hitch to accommodate higher TT...

What I feel is that when a semi passes me the TT gets pushed over more resulting in me getting closer to the truck and requiring a bigger steering correction. I have a hard time believing that 1" in height causes this and suspect that it's the tires that are softer. I'm currently a couple PSI below max inflation and I'll pump them up to a few PSI above max for the way back to see whether that helps.

Live and learn... but if you're looking for R15 tires, you may want to check for something stiffer than the Yokos. Although, of course, I may be completely wrong in my diagnosis... Is there any metric for sidewall or tire stiffness I might be able to look up?

You got the wrong ones. These are the heavy duty ones.
Yokohama*RY215

[tvoneicken]

Originally Posted by mstephens

Quite as number of people changed from GYM to MICHELIN LTX in the past year. I know I am very happy with mine. What tipped you over to try the Yoko instead of the Michelin?

There are no Michelin LT tires for 15" wheels. They're all 'P'=Passenger.

[tvoneicken]

Originally Posted by r carl

You got the wrong ones. These are the heavy duty ones.
Yokohama*RY215

Mhh, thanks for the pointer! I'll check them out when I get back home and have some more time.

[mstephens]

Originally Posted by tvoneicken

There are no Michelin LT tires for 15" wheels. They're all 'P'=Passenger.

I may have forget the "X" when I typed. The set I bought were Michelin 235/75R15 LTX M/S. You can look at them here: LTX M/S2 | Michelin Tires

Michelin refers to them as tires for light truck and SUV.

[tvoneicken]

Originally Posted by mstephens

I may have forget the "X" when I typed. The set I bought were Michelin 235/75R15 LTX M/S. You can look at them here: LTX M/S2 | Michelin Tires

Michelin refers to them as tires for light truck and SUV.

You most likely bought your tires before Michelin discontinued the model. Follow your link, click on "specs" (top center), you will see that the only tire in the size you quote is "part #36210 -- P235/75R15/XL 108 T". Sadly there is no LT...R15 in the list. My tire shop checked with the Michelin rep.

We can, of course, speculate whether the P models actually differ from the LT models or whether that's just a marketing gimmick... I honestly have no idea...

[CapriRacer]

Originally Posted by tvoneicken

........We can, of course, speculate whether the P models actually differ from the LT models or whether that's just a marketing gimmick... I honestly have no idea...

You'll have to trust me on this, but they are different.