Michelin LTX 235/75R15 XL Upgrade?

[Steve Bryant]

If you plan to keep your trailer for any length of time and I were going to buy new wheels, especially aluminum wheels, I wouldn't consider anything other than 16" wheels. You can still buy the Sendel 16" diameter for under $120 each from multiple sources, here's an example. Even if I were going to stay with steel wheels, I'd move to 16" wheels (steel if necessary for the price point) for the following reasons:
1. 15" tires have not been produced for light trucks for over a decade.
2. The demand for light truck replacement tires is what drives the availability of suitable replacement trailer tires other than those used for light duty, short distance hauling.
3. I've owned three travel trailers since the 1980s and ST tires are not what they used be as we all know.
4. I think that the tire manufacturers look at ST tires as being a niche market and that's why most of these tires manufactured in the past decade have been made in China.
5. Tires like the 275/75 15 LX are less likely to be available in the future than they are now.


Now, if I only took short trips, had a very lightly loaded trailer, planned to keep the trailer only a short time longer, I'd be tempted to stick with 15" rubber. Otherwise, I'd do this differently. I do agree that most travel trailers do not need load range E tires, but that's not a question posed by the original poster.

Steve

[RLS]

Originally Posted by Steve Bryant

If you plan to keep your trailer for any length of time and I were going to buy new wheels, especially aluminum wheels, I wouldn't consider anything other than 16" wheels. You can still buy the Sendel 16" diameter for under $120 each from multiple sources, here's an example. Even if I were going to stay with steel wheels, I'd move to 16" wheels (steel if necessary for the price point) for the following reasons:
1. 15" tires have not been produced for light trucks for over a decade.
2. The demand for light truck replacement tires is what drives the availability of suitable replacement trailer tires other than those used for light duty, short distance hauling.
3. I've owned three travel trailers since the 1980s and ST tires are not what they used be as we all know.
4. I think that the tire manufacturers look at ST tires as being a niche market and that's why most of these tires manufactured in the past decade have been made in China.
5. Tires like the 275/75 15 LX are less likely to be available in the future than they are now.


Now, if I only took short trips, had a very lightly loaded trailer, planned to keep the trailer only a short time longer, I'd be tempted to stick with 15" rubber. Otherwise, I'd do this differently. I do agree that most travel trailers do not need load range E tires, but that's not a question posed by the original poster.

Steve

Very good insight. The only thing to consider, is if going from a 14" to a 16" wheel is will it fit? I agree 100% if a person is thinking about switching to a 15" wheel they should go to the 16" one IF it will fit. They need to make sure first. JMHO

[field & stream]

A critical part of the "if it will fit" issue is the bolt pattern -- 14" wheels tend to be 5-bolt pattern, and the 15"-16" tend to be 6-bolt. Also, the 14" wheels tend to be on the trailers with less weight per axle (i.e. the current dual axle 23' or older and lighter trailers) which definitely don't need the E-rated 16" tires.

[Ridgerunner3]

Steve, Maybe I am not understanding your comment about 15" LT tires not being manufactured in over a decade.

Michelin does not make a 15" LT tire but, there are several tire manufacturers that still make LT235 75 15 Load Range C tires. Tire Rack sells 20 different models of that tire. They also sell one load range D in that size. There are also a few LT Load Range C & D in 14" wheel sizes.

[Steve Bryant]

Bud,
Good eye and good catch!!!

I misspoke. I should have said that light trucks (let's say half-ton, full size trucks or larger) have not been sold by the OEM factories (let's say GM/Ford/Chrysler/Nissan/Toyota/etc.) for over a decade. For example, on the GM light trucks (Silverado/Sierra) the last year that two wheel drive versions were equipped with 15" wheels was 1998 and for the half-ton two wheel drive SUVs (Suburban/Tahoe/Yukon) the last year for 15" wheels was 1999. The four wheel drive versions of all of these vehicles have come equipped with 16" wheels since 1988 (pickups) and 1992 (SUVs). It's my recollection that the other domestic and import OEMs changed to a minimum of 16" wheels at about the same time. Now, it's not uncommon to see 17 through 22 inch wheels for full size (or even "compact") trucks from the factory. On passenger cars, the trend is toward large diameter wheels and ridiculous aspect ratio tires for anything above a bare bones sub-compact models.

In the '40s through '80s, cars, half-ton light trucks and travel trailers all had wheel and tire sizes that were pretty common. Current trends cause the vehicle and trailer wheels/tires to diverge away from each other plus there are far fewer RVs manufactured now versus a decade ago. All of these factors combine to relegate replacement travel trailer tires to a small niche market that likely has a very small profit margin for tire manufacturers. On the other hand 3/4 ton trucks still often come with 16" wheels and the 225/75R16 tires are nearly the same diameter as the 235/75R15 tires, which is great for those with 6 lug wheels. I don't know what to say for folks with 4 lug wheels, but I'm going to look into that out of curiosity.

Also, I want to mention that I apologize for not just answering your question and instead, going on a bit of a rant. It's just that I have strong feelings about this situation and I've done a lot of personal research on the topic.

Steve

Originally Posted by Ridgerunner3

Steve, Maybe I am not understanding your comment about 15" LT tires not being manufactured in over a decade.

Michelin does not make a 15" LT tire but, there are several tire manufacturers that still make LT235 75 15 Load Range C tires. Tire Rack sells 20 different models of that tire. They also sell one load range D in that size. There are also a few LT Load Range C & D in 14" wheel sizes.

[Luigi123]

About to pick up a 2008 30ft Classic ltd that have the original tires with limited use and under cover. I will bring it home over 975 miles. I run LTX Michelins on all my vehicles and appreciate the ride, traction, and especially the long wear. My question what size do I ask either Cosco or Discount Tire to order and do I need to order new rims? I see the size most common spoke of is the 235/75R/16 LTX need some quick guidance here as I travel on the 30th of July to bring here home? I appreciate all or any of your guiding thoughts.

[Colin H]

Originally Posted by Luigi123

About to pick up a 2008 30ft Classic ltd that have the original tires with limited use and under cover. I will bring it home over 975 miles. I run LTX Michelins on all my vehicles and appreciate the ride, traction, and especially the long wear. My question what size do I ask either Cosco or Discount Tire to order and do I need to order new rims? I see the size most common spoke of is the 235/75R/16 LTX need some quick guidance here as I travel on the 30th of July to bring here home? I appreciate all or any of your guiding thoughts.

I purchased Michelin LTX MS2 235/75-15 tires from Tire Rack a couple of months ago for $143 each. They have a 2180 lb load rating so they should support your trailer just fine, without buying new wheels.
Good luck,
Colin

[Sylver Slypr]

Originally Posted by Colin H

I purchased Michelin LTX MS2 235/75-15 tires from Tire Rack a couple of months ago for $143 each. They have a 2180 lb load rating so they should support your trailer just fine, without buying new wheels.
Good luck,
Colin

I got tires here 6 mos. ago cheapest I could find,fast service,no problems 235/75R15 36210 Michelin LTX M/S 2

[Steve Bryant]

I agree with Colin that the P235/75R15 tires are still available and that they are adequate to most Airstream Travel Trailers (including mine). However, the thing that still concerns me is the future availability. If you look at Michelin's own chart on the LTXM/S2 tires, the only 15 inch size is this P235/75. I am going to be replacing my axles and I need all of the ground clearance I can get. I'll order 32 degree down starting angle. As I do this, I'm trying to think about what tire sizes will be available well into the future and I don't think that any 15 inch size will be available for more than five years from now as I stated earlier.

If I could still buy LT tires in two or three sizes from two or three manufacturers with a tire weight rating of 2,000 pound or more, I'd probably rethink my plan to go with 16" wheels and stick with the wheels that I've got. I just don't think that anything other than inferior ST tires are going to be available into the future for 15" wheels.

Steve

[Sylver Slypr]

Originally Posted by Steve Bryant

I agree with Colin that the P235/75R15 tires are still available and that they are adequate to most Airstream Travel Trailers (including mine). However, the thing that still concerns me is the future availability. . I just don't think that anything other than inferior ST tires are going to be available into the future for 15" wheels.

Steve

You also have to remember that there are literally millions of light trucks with 15' wheels on the road now and they will have a market share for quite a while.

[Colin H]

Originally Posted by Sylver Slypr

You also have to remember that there are literally millions of light trucks with 15' wheels on the road now and they will have a market share for quite a while.

Yeah, I have 3 myself, plus all of my assorted trailers
Colin

[Krazyjohnny]

I am on the cusp of purchasing new tires for my 07' 27 foot FB Safari. I have the 15 inch wheels of course and have not had the same results finding the multitude of different LT tires in 15 inch as mentioned above. The Michelin LTX MS2 with the XL load rating is 1985 lbs per tire. My GVWR is 7600. Once I derate (10%) for being passenger tires they do not qualify for the correctly rated tire for this trailer. Is there somethng I am missing ? We bought the trailer new 07' and this is our first tire change since we bought the trailer. We have had no issues with the Goodyears, but reading here has got me started thinking for sure.

[DMT]

1985 x 4 = 7940

7940 - 794 = 7146

[SteveSueMac]

Originally Posted by Top

Yes they are.

Ok. I am either a sheep or a smart consumer (you be the judge but don't tell me your opinion :-) )

At this site you linked, the tire is rated at 2183. Dividing by 1.1 derates the tire to 1984. On 4 tires that's 7938 capacity. Divided again by 1.15 for 15% headroom (on the already 10% derated tires) leaves 6902 capacity.

Last trip to scales, trailer weight (both axles on one scale) was 5880 (call it 6000 to be safe). Tongue at 1140. This includes:

Full WD applied
ProPride hitch
1/2 fresh water full
2 full 30 propane tanks
Camp loaded (gear, clothes, dishes, liquids, etc)
Empty gray and black tanks.

Am I correct in assuming that putting these tires on would still give me 900+ lbs capacity in the trailer? If so, I'm starting to think I should get a set of 4 and pop them on the trailer before a long trip this month. You all have me freaked out about the GYMs despite their 10.000+ lb capacity.....I really don't like the idea of going up to 16s but if these 15s can do the job well...I'm really tempted.

Thoughts/comments/suggestions highly welcomed!!! :-)

Edit: trailer is 27FB Flying Cloud 7600 max weight

[DKB_SATX]

Originally Posted by SteveSueMac

~~

Am I correct in assuming that putting these tires on would still give me 900+ lbs capacity in the trailer? If so, I'm starting to think I should get a set of 4 and pop them on the trailer before a long trip this month. You all have me freaked out about the GYMs despite their 10.000+ lb capacity.....I really don't like the idea of going up to 16s but if these 15s can do the job well...I'm really tempted.
~~

I think you're understating, even. "900+ pounds of reserve capacity AFTER a conservatism factor of 15%" would still be fair to say.

I only have about 3200 miles on the Michelins, in a year of travel in hot weather and cool, but every time I have measured (which is generally every stop) they have been closer to the ambient temperature than the Carlisle STs they replaced, and they maintain air pressure MUCH better over time.

I'll be putting a set of the Michelins on the 28' rear-bed Argosy when that's ready for the road.

[Krazyjohnny]

DMT,

Your math is the same as mine. I have not seen any manufacturers spec of a higher rating for the Michelin LTX ms2 XL than 1985 lbs. Where did the above poster come up with the 2183 figure? If that is listed somewhere credible I would feel better using them on our trailer.

[DKB_SATX]

Originally Posted by Krazyjohnny

DMT,

Your math is the same as mine. I have not seen any manufacturers spec of a higher rating for the Michelin LTX ms2 XL than 1985 lbs. Where did the above poster come up with the 2183 figure? If that is listed somewhere credible I would feel better using them on our trailer.

It's the number that's stamped on the sidewall...

[Krazyjohnny]

I will have to look at that on my wife's truck when I get home. I will also look at the tire store. If that is truly the case I will definately go that route and be done. That still allows for 200+ lbs over GVWR for the trailer. Has anyone done the math on how much the tires are actually carrying? If the toungue weight is 1000 lbs and we can just be "Simpleton's" saying that is carried by the tow vehicle, then the using the GVWR of 7600 lbs as the trailer weight, would that mean the trailer wheels are carrying 6600 lbs? 7600-1000=6600.

[switz]

The 27FB Flying Cloud and Internationals both have a GVW of 7,600 pounds. Their tongue weights are 791 pounds and 770 pounds respectfully. Rounding the tongue weights up slightly to 800 pounds, which will really be lower than reality, your rear axles, with the trailer freestanding fully loaded to maximum GVW, would be supporting 6,800 pounds. Allowing for a 1/3 transfer of tongue weight would bring the trailer axles load to 7,080 pounds.

Four derated Michelin LTX (P) 235/75R15 XL tires could carry 7,940. which is more than a 10% safety margin. The reality will probably be tongue weights approaching 1,000 pounds or heavier and that just increases the safety margin.

[Krazyjohnny]

I will be getting these this weekend if time allows. 4 new Michelin LTX MS2s. Thanks for confirming my feeble math skills.