16" wheels/LT tires

[Streamside]

Originally Posted by SRW

After reading this post I called Michelin's Customer Care at 1-800-847-3435 naively expecting to confirm that what I had been told in an earlier call was indeed correct.

The Michelin rep (Bill) said that although Michelin did NOT make a tire specifically for use on travel trailers they were aware that the Michelin LT XPS RIB tires were being used with travel trailers, and in fact was providing good service.

He also said if a consumer wanted to use a Michelin tire on a travel trailer the XPS RIB was the best choice due to its stiffer sidewall.

He went on to say that most likely the reason that Michelin did not "recommend" their LT XPS RIB for use on travel trailers was due to a lack of testing, and that would no doubt change in the future.

Hmmmm.

I agree with your thought...."Hmmmm." Sure would be nice if it came in the 225/75 15 for those of us that don't need to cash out the farm just for a good set of wheels and tires.

thanks for your digging and I too have emailed M for further clarification. When (if) I get a response, I will post here.

thanks and keep digging

[SteveH]

I believe when the time comes I will go to this 15" tire:

Michelin LTX M/S2

Click on the "specs" section and read the weight capacity and size. This would let us go to a Michilin LT 15" tire with the capacity to haul our trailers, and not have to change wheels.

[Wayne&Sam]

Originally Posted by SteveH

Click on the "specs" section and read the weight capacity and size.

But the max pressure is only 50psi.

[Antique Pedaler]

There must be some livestock trailer owners on this forum. Around this part of the world they run Michelins up and down the highways at the speed limit with four horses, tack and a few bales of hay on the trailer and never seem to have any problems.

[Gene]

After reading Steve's post, I looked at the Michelin website and see that most LTX tires are no longer rated as mud and snow even though many are called LTX M/S. They have pretty good snow type tread, but they are called all season. I wonder if something has changed in what you can call mud and snow? The mud and snow LTX tire is called LTX Winter.

Another strangeness is that LTX doesn't necessarily mean light truck anymore. Some are passenger and some are light truck tires—check for prefix P or LT. Long ago Michelin X was the car tire, and then came the light truck Michelin X called LTX.

The P tires carry less weight than the LT tires.

Now LTX doesn't always mean what it used to and M/S means all season, though I have tires that are M+S, i.e., mud and snow (I hope).

Some people want to get the RIB, but it is definitely not a snow tire. It's called a summer tire and the tread looks it. They also state it is not for heavy rains, it's for "mildly wet conditions".

Gene

[SteveH]

Originally Posted by Wayne&Sam

But the max pressure is only 50psi.

But the WEIGHT CAPACITY is 2184 Lbs at 50 psi. My Airstream weighs 6700 pounds which is well within the 8736 pound capacity of four of these tires.

There are actually some folks on here that advocate running "D" rated tires at under the max pressure to get a smoother ride for their trailer.

[Phoenix]

Well, we finally converted from 15-inch to 16-inch wheels so that we can run LT instead of ST tires and get the blowout nightmares behind us. Special thanks to those of you who provided advice and gave me the confidence to finally make the switch.

The following is a compilation of others' experiences and opinions, and personal research on 16-inch wheels and tires. Hopefully, the photos and details below will help others with 19-foot Bambi's that have been contemplating this conversion, to decide for yourselves if this is the permanent fix you seek. (Other Airstreams seem to have more clearance in the wheel wells, so this isn't such a hard decision to make.)


A Little Background...

Without going into a lot of detail, we had a blowout on our 2005, 19-foot Bambi near Mexican Water, Arizona in July of 2008. We were on Highway 160 just east of the junction with Highway 191, on the Indian Reservation (that's about half way between Kayenta, Arizona and Cortez, Colorado, near the Four Corners area), when we saw one of our three year old, Goodyear Marathons (that used to be on our trailer) come shooting out of the wheel well like an ICBM coming out of an underground silo, smoking and slinging chunks of rubber, and head out across the desert. Because we were on a wide sweeping curve, I decided to pull half off the shoulder to keep from being side-swiped by cars and semi's. Bad idea -- The dirt is Lake Powell sand (really soft, like sugar) and the trailer immediately sank up to the frame with the bare rim and what was left of the bead, partially buried in the sand. There was no way a jack was going to get under the frame. So, I figured I'd just pull back up on the shoulder. No way, now I'm stuck in the sand.

Well, anyway, four and a half hours later, after a mile hike on a desert highway in 110+ degree heat with no hat, no water and wearing sandals, and a high-speed ride locked in the back of an Arizona Highway Patrol car in search of a slightly elevated ridge 15 miles away that had cell phone service so that I could call our insurance company, a tow truck finally arrived to figure out how to change our tire and get us back onto solid ground. By the way, having lived in Arizona for over 30 years, I already know the following:

1. Stay with your vehicle; don't hike to the nearest gas station in the heat of the day, especially when they don't have a tow truck and their pay phone is broken.

2. Wear a hat and sturdy shoes, carry extra water, and stay out of the sun as much as possible; don't go hiking on the highway in 110-degree weather in sandals, without the hat and ice water you left in the truck.

3. Don't accept rides from strangers (unless they are police). The highway patrolman said that he would take me to a phone. When we drove right past that gas station/restaurant at about 80 mph, I realized that I was locked in the back of a car with no door handles, not wearing a seat belt (there weren't any), and I didn't know where we were going. (Uhhhh, HELP!)

4. Weigh your decisions carefully. If you are on an Indian Reservation in Arizona and you need a tow truck to come from 90 miles away, on the Sunday afternoon of a three-day holiday weekend, do you want to it to come from Colorado or New Mexico? (I'd like a local, please...)

Uh-oh, I'm making a short story long, now... Sooooo, $450 dollars later, we were back on the highway, headed for Cortez, Colorado in search of the elusive 15-inch ST trailer tire that isn't a Goodyear Marathon. And, the only regular tire store in town that has a 15-inch ST tire is... the Goodyear Store. Well, you get the idea.

Anyway, later, back in Phoenix, I researched tires and decided that 16-inch wheels and Michelin XPS Ribs were the bullet-proof solution to blowouts. So, our tire-guy, Paul (old-timers always have tire-guys, yard-guys, paint-guys, etc. It comes from being so old that they finally remember you when you keep coming back in for more stuff. This can be accelerated by owning an Airstream that has lots of tire failures, so they can remember you faster!) -- Oh yeah, so Paul helps us pick out some 16-inch wheels. However, a couple of days later when everything arrives (how did you guess, all special order stuff) and we get the XPS ribs installed, they won't fit into the wheel wells. (I'll explain why later in this saga.)

So, plan B: Special order the 15-inch, Maxxis ST tires.

Jump ahead two years -- I finally got Centramatics from Santa (and Andy), and I decided to install them a week ago, on a beautiful Saturday afternoon. I figured it would take about 15-minutes per side. So.., three hours later, I got one side on, after playing with the Centramatics for awhile and wrestling with the one tire. Then, I finally remembered that you have to let the air out first. And, I found out how long it takes to pump a tire up to 80 psi with a little, portable air compressor. (By the way, that's about an hour.)

Now, I'm pooped... It's 4:30, so I decided to take the trailer up to Discount Tire before 5:00 PM when they close, and they can install the other Centramatic. By now, I'll gladly pay double what I was trying to save, just to have them do it; and that's for just one side! So, they got the wheel off, and... the belt was separating. Dang! At least, I got the extended warranty. After the big blowout, I was running scared, and I paid extra for the warranty, when I normally would just take my chances. It paid off this time. Unfortunately, I thought the Maxxis tires were the "final fix" for blowouts. Now, I'm back at square-one. -- So, that's how we revisited converting to 16-inch wheels and XPS Ribs.


A Little Analysis...

Alright, before we spend a hunk of money on this, I need to figure out why the 16-inch wheels didn't fit two years ago, and why they should work now.

After rethinking what happened before, I remembered that I told Discount Tire not to jack up the trailer on the axles, and they put the jack on the shock mounting bolt and jacked up the wheel, instead of the trailer. So, the wheel was still all the way up in the wheel well, which reduced the clearance between the hub and the outer edge of the wheel well. Also, they ordered 7-inch wide truck wheels that had a slight offset (don't remember how much). So, if I order 6-inch wide trailer wheels with zero offset, this time (which is what Airstream recommends), the cross-section width of the tire should be narrower.

Comparing the cross-section width of the 225/75x16 Michelin XPS Rib versus the 225/75x15 Marathon, both on 6-inch wide rims, the width is nearly identical. In fact, almost all of the other dimensions are the same, except for the tread width (the XPS Rib is a little wider) and the overall tire diameter (again, the XPS Rib is about 1 inch larger, which translates to 1/2 inch loss of clearance in radius, per side). So, if I can get the XPS Ribs into the wheel wells, there should be plenty of clearance (I just need to remember to let the air out).

OK, time to try this out -- It should work this time.

Discount recommended the Sendel T02 or T03 wheel (see exact specifications near end of this entry), and I decided to get XPS Ribs instead of the Michelin LTX M/S 2 light truck (LT) tire. Basically, I figured if I was going to do this, I should get the best. I know that I am almost certainly going to end up throwing away a weather-checked tire in about five years, that still has lots of tread left; but it will be worth it to end this tire madness. No more new tires every two years after a blowout on the road. No more wheel well damage. No more worrying when the speedometer creeps up to 65 on the highway when you aren't looking. -- Nope, it's worth the extra money, for the peace of mind.

So, we got the new wheels and tires, today. Attached are photos, and the exact wheel specifications appear below. As near as I can tell, the wheels visually appear to be the same size, even though I know that they are just slightly bigger around. The slight interference getting them into the wheel wells seemed the same as with the 15-inch wheels and tires they replaced (both deflated). And, the height on the trailer is very slightly higher and closer to level, with the new tires; although, if you didn't know I switched wheels, you probably couldn't see the difference by looking at the trailer from across the street.

If you decide to consider this conversion, it's entirely your choice. However, I personally regret having waited two more years and buying two extra tires to come to this decision. The XPX Ribs are the most expensive tire I have ever purchased, but my wife and I look forward to the coming years on the road with "normal" tire problems (nails and stuff), instead of catastrophic failures. Goodbye Marathons!

=====================

Wheel size: 16x6
Bolt Circle: 6x139.7 (same as 6x5.5)
Offset: 0 (zero)
Center Bore: 4.25
Load Rating: 3,200

Note: The clean tires in the photos are the XPS Ribs, and the dirty ones are the Maxxis tires. The last photo is of our wheel boot. It isn't supposed to fit 16-inch truck wheels, but it fits better on the new 16-inch Sendel wheels than on the OEM Airstream 15-inch wheels.

[dscluchfc]

Hey Phoenix! Good to see you on the forums again and get an update on your tire sagas. I had one of my own in June 2010.

Coming back from Yellowstone, I had to buy 4 new tires in Roy UT as I caught two of the ones I had on separating and bulging. Because I had to buy under duress, I got 4 Carlisle tires and went to the Load Range E tire.

I have since researched the tire thing and have determined to go with 16s and get the Michelin next time I need to do this.

I hope you and your family are doing well in 2011.

[UAPachyderm]

I just made the change as well. I regret I waited until my third ST blowout and second wheel well repair before making the change.

Sent from my iPhone using AIR Forums

[Phoenix]

Update: Took a long weekend including Valentines Day and went on a little roadtrip north of Phoenix, through Prescott, Yarnell, and down by Lake Pleasant. On a lightly travelled 2-lane highway, I got in our Airstream for a couple of miles to see how the new XPS Ribs and Centramatics rode, while my wife drove at 55-60 mph. If I closed my eyes, I couldn't tell the difference between riding in the Airstream and riding in our 2008 Tundra CrewMax; i.e., very smooth, with a little bit of road feel (I could feel little irregularities in the road surface, but definitely no wheel/tire balance problems). Unfortunately, I never rode in the back before we got the new wheels and tires, so I have no idea if this is an improvement or not; and my wife won't ride in the back again. We have some friends that also have a 19-foot Bambi with the OEM wheels and tires, and I may see if he'll give me a ride in their Airstream for comparison.

In any case, in my opinion, the comments about Load Range E tires inflated to 80 psi riding hard and damaging a TT is just a myth. Just my seat of the pants estimate, but I really doubt that Load Range D tires inflated to 65 psi would feel any different. If I get a ride in our friends Airstream, I'll update this post, again.

It sure was a relief not worrying about tire failure while we were on the road.

Also, I got an infrared thermometer at Harbor Freight, and after about 50 miles at 60 mph, the hubs were 5 degrees hotter than the ambient air temperature, and the tires were 10 degrees above that. Surprisingly, the front tires of our Tundra were the same temperature as the Airstream tires, and the rear pickup tires were 10 degrees above that. Not sure this means anything, but it was nice to know that the new tires run cool, too.

Ambient Air Temp = 75 degrees
Airstream hubs = 80 degrees
XPS Ribs (TT) = 90 degrees
Tundra/front = 90 degrees
Tundra/rear = 100 degrees

[Inland RV Center, In]

Originally Posted by Phoenix

In any case, in my opinion, the comments about Load Range E tires inflated to 80 psi riding hard and damaging a TT is just a myth. Just my seat of the pants estimate, but I really doubt that Load Range D tires inflated to 65 psi would feel any different. If I get a ride in our friends Airstream, I'll update this post, again.

Airstream and Argosy trailers, "MUST" have a soft ride.

If not, damages will occur.

Excessive rated tires, excessively inflated, along with unbalanced running gear, are just some of the known causes of damages, for over 50 years.

Service department records, pertaining to those damages, speaks for itself.

Andy

[moosetags]

I recently got the 16" wheel/Michelin E package at Jackson Center. I specifically asked about what tire pressure they recommended. I was told that they recommend 80 psi. I made the conscious decision to run Lucy's at 72 psi.

Brian

[Gene]

I was told the same thing at the service center that Brian was told. I told them to inflate to 68 lbs. and they did. On D range tire, 65 lbs., the maximum recommended for that tire, is appropriate for the heavier trailers, so their logic must be to always inflate to the maximum for any tire. No one inflates their truck or car tires to the maximum unless they are carrying a really big load. Check the pressure needed to support the weight of a fully loaded trailer and go with that.

After many, many miles the Michelins are wearing evenly showing no signs of under- or overinflation.

Gene

[HowieE]

99% of the trailer s out there are running with over inflated tires because the tire dealers just inflate to the MAX.

If you know the weight of your trail and refer to the manufactures inflation chart you will find the correct pressure for your tires. Your will be surprised at what you find. My tri axle with E rated tires calls for less than 40#.

Since the Government requires all manufactures to make each given size tire to the same standards this chart will work for other makes of tire of the same size. http://www.goodyear.com/rv/pdf/rv_inflation.pdf

[SRW]

Howie:

I have not seen this chart before, and very much appreciate your posting.

My LT's came from Discount Tire, and they did indeed say inflate to the maximum.

Figuring the weight of my Airstream riding on four LT225/75R16 tires the inflation pressure should be 65psig not the tire's max pressure of 80psig.

Interesting, that the chart you posted is dated 01/01/2005 and although a footnote says that the info is in, "the process of being revised" the same chart is in Goodyear's RV Tire and Care Guide dated 08/05/2008.

Thanks,

[48Bob]

I used a similar chart after weighing our fully loaded Safari to determine the correct pressusre, and it was well below the maximum.

[HowieE]

Originally Posted by 48Bob

I used a similar chart after weighing our fully loaded Safari to determine the correct pressusre, and it was well below the maximum.

Please tell others because as I noted above most people are running grossly overinflated tires.

[48Bob]

The key is to weigh the trailer as it would normally be loaded, then possibly add 100-200 pounds as a safety margin, and then use the appropriate chart to determine the correct inflation pressure.

[Action]

Originally Posted by CrawfordGene

......, so their logic must be to always inflate to the maximum for any tire. No one inflates their truck or car tires to the maximum unless they are carrying a really big load.

Most trailers are supplied with tires that just meet the max load. And the towed load is usually a small window. (Not so with passenger car and ALL TRUCKS) So a trailer manufacturer will not supply a tire that has a lot of extra weight carrying capacity. It is just wasted extra money. Multiply that by the number of units a manufacture puts out and that eats into profit. So including a tire that the max load is say 1880 pounds and the actual load runs between 1750 and 1850, well just max out the tire pressure to handle the max loads encountered.

Versus the other extreme which is a pick up truck. The load swing for a truck can be huge! (Many hundred pounds) And the tires supplied have to handle that load. To compensate the inflation charts are created to handle the swing in loads.

Now replace tires and the consumer may step up and get a larger capacity tire fo rthe extra $. Then you have some room to play with pressures depending on load other than max pressure.

Andy's post above has some merit regrding ride quality if the over capacity tire is maxed out in pressure. In my non-professional opinion this is only if you max the pressure in an over capacity tire. I don't buy the advise of a over capacity tire with less than max pressure to match the actual load will do any damage. However I get to live with my decisions and everyone else gets to live with theirs.

>>>>>>>Action

[SRW]

The inflation chart for RV LT225/75R16 XPS RIB tires on the following Michelin web site lists the same inflation/weight capacities as the Goodyear LT chart.

Michelin North America RV Load & Inflation Tables

LT's seem to have the same weight carrying capacities - at least if they are made by Goodyear and/or Michelin?