Tires ??

[Mooney]

225's are not an option for us right now, as our rims are a mere 5 inches wide....the 225s really need at least a 6" rim, but could work with a 5.5" one....

I've ordered the Marathons, with specific instructions that I want North American made tires, no Asian junk.

Here's a cool website I found, with links to all the DOT code plants the mfgs. use, and where they are from .

http://www.tireaccidents.com/tire_plant_codes.htm

...only problem is I hit the PRINT button before realizing that the file is 26 pages long.....

at least I'll know if they listen or not (and I am not taking Asian junk tires again, on ANYTHING).

Michelin tires, including the LT versions are (or were, in 1997 when I was at the corporate HQ in South Carolina for training) built for a smooth ride and comfort, which is mainly a funtion of the sidewall. Their sidewalls are made with a very "soft" area, pretty much centered on the sidewall, where they are fairly weak. We used to do a lot of sidewall blowouts (always a "My wife had my car and..." situation ) with Michelins.

Michelin, BF Goodrich, and Uniroyal are all owned by the same company (Michelin).... Michelin marketed as the "premium" i.e. Caddys, Mercedes, etc.

BFG was marketed as the performance brand i.e. muscle cars (how many have we seen with BFG Radial T/As? I bet you've seen a ton whether you know it or not), off roaders, etc.

Uniroyal was the "reliable yet inexpensive" tactic.... a good value for the
"dollar conscious" buyer....

Good marketing strategy, especially since they are not typically cross-promoted as being under one corporation.

BONUS POINTS: What is the Michelin Man's "name"????? no cheating, does anyone know?

[Hematite]

Off the top of my head I seem to remember his name is Bibendum or something like that. At least that's what I remember from probably the '70's. And no I never worked for the company, I just thought it was a curious name! Is that correct?

[Hematite]

rich2500 brought up another manufacturer of ST tires: Denman. I know of Denman through the old car hobby. I checked and Denman has the ST tires made in Mexico which is likely much better than made in China. I didn't find any negative opinions about Denman, either.

http://www.sunlineclub.com/forums/ph...pic.php?t=1999

[Hematite]

The Denman Express ST Radial is claimed to be the best trailer tire on the market. Considering all the other ST tires are Chinese manufacture, that's not hard to belive! LOL!

http://www.denmantire.com/catalog/22.pdf

[emam]

I looked on my rims and cant find anywhere that says 55lb psi max?

When I had the guy put the tires on the rims, stock 5" wide rims, I asked him if the 225's would fit and he looked something up and said "Yep, no problem."

I would think if there was going to be a problem, he would have tried to upsell me into gettting bigger rims. Something I'd like to do anyway, but havent yet dropped the money.

[henryj]

I have been reading various tire threads here and elsewhere with interest as I expect to replace my current tires for the first trip next spring. I had never thought of using LT tires, but it sounded like a good idea, so I did a little research and decided to write a dissertation to clear up some of the confusion.

First some definitions. The tires we drive down the highway come in 3 categories. P, or passenger, tires are OEM on everything from a Civic to a 1/2 ton and SUV. A typical size on a 1/2 ton would be P235/75R16. Although it is rarely stated, these tires are load range B, or LRB, and inflated to 35 psi.
LT, or light truck, tires are OEM on 3/4 ton and larger pickups. Most of these tires come in LRE with a fair number of aftermarket LRD and virtually no LRC. They can be inflated to 80, 65 and 50 psi respectively. A typical size on a 3/4 ton is LT245/75R16 LRE.
ST, or special trailer, tires come in a broad range of sizes and load ranges and Carlisle still makes a lot of bias tires as well. My 2499 has a typical mid-size ST205/75R15 LRC. inflated to 50 psi and mounted on a 5" rim width.

So here's what I found, mostly on websites like tirerack.com and Carlisletire.com with some googling for other info.

1. Availability
The big attraction of LT tires on a trailer is that many of us use these tires on our trucks and are very happy with their performance. There is also a huge replacement market of high quality tires for the choosing. However, the first thing I found was that LT tires in typical trailer sizes are even more scarce than ST tires. I could not find any LT205/75/R15 for my trailer. When I moved up to LT215 only two tires came up. Michelin's LTX M/S has an LT215/75R15 LRC tire, but its max. load at 50 psi is less than the max. load of an ST205 and it weighs 10 lb. more! Hmm, maybe ST tires really are stronger. Goodyear's Wrangler HT also comes in an LT215/75R15, is an LRD tire and at 65 psi carries over 200 lb. more than the ST205. However, it is also significantly heavier than the ST205 and at 50 psi it too carries less weight than the ST205.

To sum up availability, Goodyear's LT215/75R15 LRD is the only LT option that can even be considered.

2. Tread Depth
ST tires have a shallow tread depth, 9/32", to reduce tire squirm and possible sway. The LT is 13/32"

3. Rim Width
The 2499's 5" rim is the minimum recommended for the supplied ST205 and is rated at 50 psi. The LT215 requires at least a 5.5" rim and 55 psi to match the ST205 load capacity. This is not a big concern as trailer rims are spec'd to the lowest common denominator. A 5x15 rim is rated at 1820 lb. at 50 psi because that's the rating of the ST205 tire it will most likely carry. No manufacturer would bother rating it higher when there is no suitable tire available. You could probably get away with an LT215 on this rim, but read on.

4. Construction
ST tires have more rubber in the sidewall to make a stiffer carcass less prone to sway. There is also some additional protection from inadvertent curb impacts. Mounting the softer LT tire on a smaller than recommended rim at 15 psi under its recommended max. will promote sway.

5. Weight
I have no idea where the extra weight in an LT tire goes. The extra rubber on the tread doesn't seem possible to account for all of it, but size for size ST tires are lighter and stronger than LT tires. The LT215 tire weighs 8 lb., or 1/3 more, than the ST 205. With a larger more appropriate rim size easily 20 lb. of weight will be added to each axle by the LT215. Adding unsprung weight is never a good idea. Unsprung weight is the weight of the components that sag down when the frame of a vehicle is jacked up. Unsprung weight is accounted for in manufacturing and messing with it by increasing tire and wheel size causes the ride quality to deteriorate. The heavier tire and wheel don't want to bounce as much on bumps giving a jarring ride, but when they do bounce they have an added momentum that really works the suspension to create a rough ride and far more wear and tear generally on the whole coach.

6. Braking
The bigger heavier LT215 tire and wheel is harder to get rolling and harder to stop once it is rolling. Think of this as a "flywheel effect." It can be easily demonstrated by any number of kids' toys.

7. Pressure
ST tires should always be inflated to their max. psi. On my ST205 LRC tires that is 50 psi. So what do I do with the LT215? Inflate them to 55 to get the ST's equivalent load capacity and they are soft and mushy; inflate them to 65 and they ride hard and stiff on top of the unsprung weight they've already added.

8. Load Capacity
The extra load capacity of an LT tire is often cited as a reason for switching. This is a myth. LT tires are just not available in sizes appropriate for our trailers. And the big strong LTs on our trucks would never fit into the trailer's wheel wells nor have any clearance between the leading and trailing tires, not to mention that those tires alone weigh up to twice what the ST205 does. Furthermore, none of us can use the extra load capacity. My 2499 has two 3500 lb. axles with four 1820 lb. tires. While this may seem a little close for comfort at first glance, my road ready weight distributed hitched up coach has an axle weight of just 4720 lb. Even Kitty's fully decked out 2499 (see another thread) has almost 2000 lb. reserve capacity in the OEM ST205.

9. Sway
Trailer sway results from a complex interaction of factors. Besides tongue weight, TV wheelbase, TV rear overhang, TT wheelbase, proper anti sway, wind, speed etc... there's also tires. I don't think LT tires by themselves will cause a well balanced rig to sway, but if I'm coasting downhill at 70 mph and have to brake for a deer, I want everything to be on my side.

10. Conclusion
Unfortunately, for me, the promise of LT tires does not stand the test of a critical analysis and I'll be sticking to an OEM quality ST replacement tire, probably Goodyear Marathons to have a tire that is readily available across North America. In deciding which tire is best for your situation, set up two columns of pluses and minuses. In my columns all the pluses are under the ST and all the minuses are under the LT. Tires are at best a compromise. For my type of driving and the roads that I travel I think Sunline picked the best overall tire at ST205/75R15 LRC.

One situation where I would still consider LT tires is a large 5th wheel with 16" rims that would take the same LT tire as my truck uses. I don't think there would be any significant minuses and some pluses in that situation.

Henry

[Mooney]

Originally Posted by Hematite

Off the top of my head I seem to remember his name is Bibendum or something like that. At least that's what I remember from probably the '70's. And no I never worked for the company, I just thought it was a curious name! Is that correct?

DINGDINGDING!

Nice work Rick!! As always, I am impressed by the breadth of knowledge in this 'net group!

I can't wait until next week when I get the new treads put on (IF they are USA or Canada made) when I bust out the list of tire plant codes and check the DOT numbers.

I honestly don't care if I anger them, it is a Goodyear retailer (under the Goodyear name)- they should have at least a little say in the supply chain (and they have a couple weeks to get it right) and they promised that they would be "local" tires.

Henry, as always- NICE POST!

[JohnB]

Henry

Very good typing and info. Thank you.

On your one point:

Henry Wrote:

9. Sway Trailer sway results from a complex interaction of factors. Besides tongue weight, TV wheelbase, TV rear overhang, TT wheelbase, proper anti sway, wind, speed etc... there's also tires. I don't think LT tires by themselves will cause a well balanced rig to sway, but if I'm coasting downhill at 70 mph and have to brake for a deer, I want everything to be on my side.

I fully agree and second your point 9. I can also add to it. TV Tires and wheelbase have an interaction on the suppression of sway. I myself ended up in the middle of a tire pressure experiment. On my K2500 Suburban, Reese DC and T2499 I had the rig totally optimized on TT tongue balance, hitch setup and WD. The rig was solid in every condition I subjected it to in 15,000 miles of towing. There was just no sway effects at all even in 35 mph cross winds.

Then my Steel Tex LT tires wore out and I researched tires to replace them with. I had at least 2 fellow camper towing buddies using Michelin, LTX LT 245/75R16’s on their 2500HD and F250 crew cab PU’s. They sore by that tire as others did as well. So going premium tires and not wanting to cut corners, I bought 4 for the K2500 Suburban. It has a 130” WB. As I rode out of NTB with them on, non towing, WOW the ride was great, non towing.

Then on the first camping trip towing, the entire rig had an instability with medium to high cross winds. I aired the tires as I always did on the Steel Tex, 50 psi front, 80 psi rear which use to be a rock stable rig. Those pressures also match with the K2500 Suburban’s axle ratings for max load. Now confronted with an unstable rig, I had to figure this out as in my book any sway is unacceptable. The instability felt like the back of the truck was shifting. I also had Quadrasteer in the Burb and thought it was acting up so I shut it off. Same issue.

Next was to recheck the WD and hitch setup and reconfirmed TT tongue weight. All where optimized right where they should be. Finally after digging enough I discovered it was the front end tires of the truck flexing and pivoting on the hard rear tires. Once I realized this the air pressure experiment began. 60 psi created the global shift I was after however it was still not as stable as the Steel Tex. I did 65, 70 and 75 psi on the front and ended up at 65 psi. Since 60 psi was the global shift point, the extra 5 psi was safety factor. 70 psi did not make it any more stable but did start a front end bounce type of wander and 75 even made that issue worse.

After more research I found other 2500 Suburban towers having the similar issues using the Michelin’s. They are too soft for towing. Yet the 2500 HD PU towers with longer WB’s had no issues and again swear by them while I was swearing at them….

They also gave me a goofy tread wear problem. See here after only about 2,500 miles towing. These where on the rear and the front had similar affects just not as pronounced.

Here is the rear:






Here is the front:


Here is the Steel Tex spare with 50K miles on it


If I would of kept that truck, those tires would have been traded with only 5,000 miles on them. I had to rotate them every oil change, 2000 miles to keep the wear pattern at bay. One of my 2500HD buddies was needing new ones and we where going to make a deal but I sold the truck before then. When I went from a 27 foot camper to a 32 foot camper with the K2500 Suburban, and those same LTX’s, I never regained the confident solid rig I once had with the Steel Tex. Amazing enough a 27 foot TT and 32 foot TT yielded the same feeling in the Suburban with the LTX. However I then knew how much closer to the edge 32 feet was and that was another factor in getting a different TV.

Point in all this, tires and inflation pressures are a large component in a tow rigs anti-sway program. While they do not cause sway, they do have an effect on preventing it from magnifying and keeping it in check when using friction type anti-sway type hitches. Exp. Reese DC, Equal-I-zer, Blue Ox, friction sway bar.


And Greg, thanks for the info on Michelin, BFG and Uniroyal.

John