Trailer Tires

[Roy W]

I have a travel trailer with 225/75/15 load range D tires on it. The tires are two year old Goodyear Marathons and I have had numerous ply separations on them. The actual weight of the trailer is well within the weight carrying capacity of the tires. (9200 lbs less 1000 lb hitch weight equals 8200 lb axle weight) I am contemplating going to a E range tire (Denman or Maxxis) of the same size thinking that it should run cooler (80 psi) even though I don't need the extra carrying capacity. I'm just getting tired of changing tires on the interstate with semi's going by 3 feet away. Any thoughts/comments..??

[NutNbutGMC]

I have a travel trailer with 225/75/15 load range D tires on it. The tires are two year old Goodyear Marathons and I have had numerous ply separations on them. The actual weight of the trailer is well within the weight carrying capacity of the tires. (9200 lbs less 1000 lb hitch weight equals 8200 lb axle weight) I am contemplating going to a E range tire (Denman or Maxxis) of the same size thinking that it should run cooler (80 psi) even though I don't need the extra carrying capacity. I'm just getting tired of changing tires on the interstate with semi's going by 3 feet away. Any thoughts/comments..??
I run the Marathons (load range D) on a boat trailer, about 3500 lbs. and have had no problems, although I visit a boat forum and some folks have the same issue as yourself.

I'd be much inclined to also swap over to an E range with an 8-ply side. I'd almost suspect the Marathons may be outclassed by your trailering. Not that that is a bad thing, but a more rugged tire may very well prove to be beneficial.

$0.02

[chipper]

My experience with Marathons over the past 10 years is they are "JUNK". I have had numerous seperations. I wouldn't have them again if you gave them to me.

[jsmiracle]

Roy W,

I friend of mine's father has been towing a TT for many (25+) years. His current TT is a 2004 model. He had a tire blowout on a 600+ mile (one way) trip. He was very disappointed. I will find out more about specifics and post them, if you'd like. I would likely steer clear of that specific tire model/manufacturer. It was OEM on the TT and only 2-3 seasons old.

The spare he had also blew out, but I don't think it was in great shape.

Jim M.

[88 K30]

My uncle just had 3 tires blow in 2 trips on his 3-4 year old trailer. The guy at the Goodyear shop that happended to be 1/4 mile from the last blowout (and sold him 2 new tires) looked at the tires and told him that the problem was a moisture problem. He said moisture from the ground gets into the tire when parked for extended periods and helps cause ply separation. He told my uncle he should park his trailer on top of plywood with a blue tarp (or plastic, etc.) between the tires and the plywood to help prevent moisture from getting into the tires. Not sure how true this is, but it seems reasonable?

[OC_DMAX]

I had Goodyear Marathons on several trailers with no problems. I have heard that within the last year or two, that they are now being made in China (internet rumor maybe, I never substantiated it). The last Goodyears that I had on my trailer were made in Canada (I believe). I don't trust any tire made in China (whether it is badged Goodyear or not). I needed to replace the Marathons on my 5th Wheel, so I went a different route.

Last year I switched out the 15 inch rim Goodyear Marathons with new 16 inch Rims and Michelin XPS Rib tires (225x16). Many in the various RV forums have had exception performance from the Michelin tires. The Michelins were made in Germany. I had the opportunity to handle both tires (Marathon and XPS Rib) while not mounted to the rims. All I can say is there is a substantial difference both in sidewall stiffness and in overall weight (I suspect you can guess the better tire).

[rustyk]

My uncle just had 3 tires blow in 2 trips on his 3-4 year old trailer. The guy at the Goodyear shop that happended to be 1/4 mile from the last blowout (and sold him 2 new tires) looked at the tires and told him that the problem was a moisture problem. He said moisture from the ground gets into the tire when parked for extended periods and helps cause ply separation. He told my uncle he should park his trailer on top of plywood with a blue tarp (or plastic, etc.) between the tires and the plywood to help prevent moisture from getting into the tires. Not sure how true this is, but it seems reasonable?

Somebody needs to inform the Goodyear shop that rubber is basically waterproof. UV from the Sun can accelerate deterioration of the tires, but, gimme a break...water? My motorhome sits on the ground (limerock) and the tires, loaded far more (although they're over-built at Load Range F - LR "E" is specified) than his trailer have done well. My "Bazanga-Meter" hits the pegs with a statement like that...

[Roy W]

I appreciate the comments. I agree, water intrusion causing ply separation doesn't make sense. To the contrary, I'm more inclined to agree with a case stating that a tire sitting for extended time on dirt tends to pull the oils out of the tire which leads to premature cracking in that area.

I considered converting to 16" tires which admittedly gives a greater selection of tire capacities, but I think I'm going to go the 15" load range E route and Denman tires. Having had load range D Marathons on my bassboat trailer and experiencing the same ply separation problems, my tire dealer convinced me to try the Denmans. That was three years ago, many miles later, and no problems.

Thanks again for all the thought provoking info.

[EdHale]

I have 4 Marathons on my boat trailer (5 including a brand new spare). The original set lasted 5 years about about 60,000 miles. I rotate and balance all 4 each year. At about the 5 year mark I ran over something and cut one and the other three just sort of gave up after that. I now have a set that is 2 years old and all of them look perfectly fine. My spare was purchased earlier this summer. All 5 of these tires purchased over the past 2 years say "Made in New Zealand" on the tire. They are 13" load range C tires. Nothing is on them about China.

[Dusty Trails]

My father and I took my his TT down to get tires put on it while I was getting a set on my Sub. I specifically asked for tires made in U.S.A. when I called the shop initially, given all the B.S. surrounding items made in China, and the salesman said they were. When we got there, I found "Made in China" right there on the sidewalls of all four Goodyear Marathons. My father decided to go ahead and put them on since we dragged the TT down the hill. My parents probably will not travel much, or far, before they replace the TT with a new 5th wheel, so it shouldn't be much of a concern. Incidentally, the old Marathons were made in the U.S.A. and one had a 12" strip along the inside rib of tread that had worn completely through the the top steel belt.

The Michelins I put on my Sub were made in Canada. We'll see how they hold up.

[Roy W]

Just a couple of quick facts about Goodyear Marathons. I attended a big RV Rally held in the infield of Daytona Speedway a couple of years ago. One of the seminars I attended was put on by Goodyear. I learned the following directly from the mouth of a Goodyear presenter.

"Goodyear Marathons are speed rated to only 65 mph, and the weight carrying capacity is reduced by 10% for every mile per hour above 65 mph."

"Following a number of tread separation issues in the late '90's, Marathons were improved by adding another circular belt under the tread. The tread separations had been caused by the tire ballooning (growing in diameter) at speed. The new improved tire is designated by the letter S with a circle around it on the tire sidewall."

All they could do was tap dance around the barrage of questions raised.

[NutNbutGMC]

The attraction for me to the Marathons are the availability of the 14" diameter tire. Most trailer tires now are not available in anything less than 16", maybe a few 15", but I need the 14" tire. Otherwise, I'd not use them. I have a ramp in my front yard so I don't travel very often.

[OC_DMAX]

All "ST" trailer tires are rated for only 65 mph. The load ratings on the side of the tires are only for 65 MPH. When comparing an LT tire, the load ratings for these tires are typically for around 100 MPH. The faster you go with the tire at load, the more heat that is generated. You can see which tire has more margin built into the design (when comparing ST and LT tires at the same MPH).

Did anyone ask them about the manufacturing origin of the current Marathon tires?

[EdHale]

Current manufacturing location for the 13" Marathons, I know because I have 5 of them, is New Zealand. They may be making them other places also, but New Zealand is definitely on all 5 of mine. Ed

[rustyk]

One thing that can happen with tires sitting on the bare ground is that there can be a variety of "nasties" that water can carry to the tire - such as fertilizer, insecticides, and herbicides. Any may lead to issues with the tire compound.

And keep in mind most RV manufacturers go with minimums...a friend of mine bought a very upscale 38' motorhome ($250K range) a couple of years ago, and after weighing it with full liquid load, there as less that 500 lb. payload capacity left on the tires. He and his wife took 300 lbs. of that, leaving 200 lbs. He took on the manufacturer, and they (grudgingly) replaced the wheels and tires. Larger wheels and tires can make a big difference in longevity.

[tanker]

Our Travel Trailer came with Goodyear Wrangler LT225/75R16-E tires. Each tire capable of carrying 2680 lbs. @80 psi. They certified the axles @6000 lbs. each. The tires are the week link in the chain, only capable of carrying 5360 lbs. per axle @80 psi. These tires have an outside diameter of 29.3".
The ride on this trailer was so rough that it broke 3 television's in two years, loosened various screws etc.
We looked into several air ride suspensions and settled on the "Kelderman Air Ride". However I still did not like the load carrying capability of the Wrangler LT tires, so I did more home work and found that my same trailer now being sold with Goodyear Marathon ST235/80R16-D tires. Each tire capable of carrying 3000 lbs. @65 psi. I switched to the Marathon tires mentioned here. Now I have a true 6000 lb. axle with 15 psi less air. These tires have an outside diameter of 30.8".
The trailer rides like a dream with the "Kelderman Air Ride" suspension and the larger tires with less air pressure.
We weighed my rig on a certified "Cat" scale at a Flying J Truck Stop. Loaded like we are going on a round-the-World trip! I carry 9960 lbs on the trailer tandem, and with the LT's I was limited to 10,720 lbs. So we were closer than I like to the maximum rating of the tires. Now I can carry 12,000 lbs on the trailer tandem. With a margin of an additional 2040 lbs. of carrying capacity over the 9960 lbs.
Just a note here as well. I had Marathon tires on our previous two travel trailers and never had a flat or blowout. However I did have three Goodyear Wrangler LT225/75R16-E tires that came on our present travel trailer fail. One at a truck stop in Wyoming, while refueling the sidewall blew out. Goodyear covered it under warranty in Salt Lake City, then I had two more that had ply separations and they also were replaced by Goodyear a year later. Hopefully Goodyear has their act together on a better Marathon tire, as I have heard many many horror stories of their failures in the past. Is this why our trailer was built new without ST tires? Sure makes me think so.
Just thought I'd add my 2 cents here with what I experienced with trailer tires.

[Inspector]

I just returned from a six week trip into the moutains of upper Utah and Wyoming. Before I left I inspected my tires on the fiver and discovered that the new tires that I put on in May were already weathering. I took the fiver back to the store that I bought the tires from and they gave me a full credit and I had them put on a set of Michelin 235 16R LTX light truck tires. Other than making sure that the tires remained at the proper inflation (80lbs) I had no problems.
The set that I had put on in May were Carlisles. I had them ordered and put on at Discount Tires in St. George. They are a reputable dealer and I have purchased tires from them for many years. I thought (mistakenly) that a set of ST tires on my fiver in this climate ( St. George Ut.) would be a better choice but having seen them weather so quickly has changed my mind. I might add that the manufactures dates on those tires were within three months of installation on my fiver.
I had LTs by another manufacture on the trailer prior to the Carlisles and had no problems with them. I had dicided to take them off as they were going on 5 years old and some sidewall weathering was apparent.
To be sure I will be watching the Michelins closely and taking every precaution to keep them in good condition.
I use a water based tire dressing and always keep them covered when Im not on the road.
I always check tire pressure in the morning before towing when the tires are cold.
I have had problems in the past with tires especially Goodyears and will probably never use them again.
I hope that Michelins LTs hold up as well as the last set of LTs. did.
Denny

[Mountainman]

You didn't mention what brand of tire dressing that you used. If you don't mind me butting in, I would like to recommend 303 Protectorant, a product I have had excellent experience with. I think you'll find that it does a super job on sidewalls used periodically on all surfaces.

[NutNbutGMC]

..... I would like to recommend 303 Protectorant, a product I have had excellent experience with. I think you'll find that it does a super job on sidewalls used periodically on all surfaces.303 has several lines of proucts that I too would recommend. The 303 products were initially developed for aerospace applications (i.e. 303 Aerospace Cleaner,303 Aerospace Protectant, 303 Vinyl & Fabric Convertible Top Cleaners and 303 Fabric Guard), not that aerospace is a special disciplne of use. I use the 303 vinyl application on the interior of my boats.

http://www.303products.com/

As for the tires, outside of a chemical treatment, there's no better way to protect them than to shield UV exposure with a material cover. I also lift the frame on my trailer and set it on blocks to get some / or all of the weight off of the sidewalls. I don't necessarily lift the tires completely off the ground but I'll lift and wedge concrete blocks under the frame (enough to take the bounce out of the trailer when one walks through it).

US$0.02

[mark45678]

I upgraded to 225/75/16" E range tires on my 31 ' holiday rambler . WHen the trailer was new it was a option to up size to 16" wheel and get away from "st " tires... It would have had 225/75/15 LR D tires that where ST rated . As stated above ST tires are only good for 65 mph , thats fairly slow if you have a oversized tow rig.

I would also put in a set of cushend equalizer to help with road shocks due to higher air PSI. A shock on each wheel makes a HUGE differance if you dont have shock on your trailer GET SOME !

Dexter sells EZ-FLEX its the cheapest product of its kind and works , trailair works better but at 3 times the price !

Monro and dexter sell shock kits that are bolt on kits also .

[Roy W]

Just an update on my original thread on having problems with Goodyear Marathons. I decided to switch from ST225/75/15 load range D tires to ST225/75/15 load range E tires made by Denman. I really didn't need the extra load carring capacity of a E load range tire, but I was tired of the problems I was having with the Marathon D range, and figured a 80 psi tire would at least run cooler. The result was something I hadn't planned on. I started on a 2000 mile trip on the new load range E tires at 80 psi. About 50 miles into the trip I started to experience severe trailer sway which I had never experienced before. I mean it was BAD. The long and short of it was the tire pressure had increased to 90 psi while on the road, and the increased pressure had reduced the tire footprint to a very small contact area on the road. Reducing cold pressure to 70 psi, which increased to 80 psi when hot eliminated the problem.

I have never experienced a 10 psi increase in hot pressure in ANY tire before, but these do. The strange thing is that the tire itself is almost cool to the touch. At least I learned how to deal with the problem, and even the 70 psi cold starting pressure is well within the load carrying capabilities of the tire, and at 70 psi the tire profile is still acceptable with no roll under.

[a5150nut]

Roy,
A company I worked for issued me a brand new Ford 1/2 ton equipped with 4 wheel disc brakes and 4 load range E tires instead of a more expensive 3/4 ton. With the tires at 80 psi all you had to do was think about changing lanes and it was over two lanes right now. Severe overstear to the point of dangerous. Ended up lowering tire pressure to 55 psi to get the truck to drive normally.

[Inspector]

The dressing that I use is a water base milk looking stuff that smells like grape juice. I get it from Discount Tire here in the west. I think that the key here is to make sure that you don't use a dressing that has a mineral base in it.
Denny

[88 K30]

Somebody needs to inform the Goodyear shop that rubber is basically waterproof. UV from the Sun can accelerate deterioration of the tires, but, gimme a break...water? My motorhome sits on the ground (limerock) and the tires, loaded far more (although they're over-built at Load Range F - LR "E" is specified) than his trailer have done well. My "Bazanga-Meter" hits the pegs with a statement like that...

I did get an update on this issue since my original post. My uncles tires didn't have water in them. The plys were separated. I found out that the trailer was not being stored on pavement, but on dirt/mud over the winter. The contstant damp and freezing and thawing over the winter cracks the rubber and allows water in which freezes and thaws more and separates the plys, and on and on. Apparently, the separation of the plys caused the blowouts. Of course, most everyone else probably stores their trailer on pavement (or at least gravel), so it probably isn't the problem.

[7.4 VORTEC]

I deal with tire consultants that work with actual tire companies. The main reason for tread seperation is not water, heat, UV, sitting on mud, lack of tire dressing, etc. Notice who has the most blown out tires when you're traveling the interstate?? RV's, camper trailers and boat trailers. These vehicles usually sits for a long time, then goes on a camping trip, fishing trip etc. When tires sit, the rubber compound and oils dry out. It is the actual driving and using of the tire that help heat up the rubber and release emollients and oils to lubricate the rubber. So many trailers and RV's sit for months at a time, only to be loaded to the max and taken on that great adventure we all hanker for. Please note!!, no amount of tire dressing, taking the weight off the tires, protecting from UV, etc is going to help. Only when you drive the vehicle can you get the tires hot enough to "self lubricate" themselves.

Learn to read your tires "birthdate". It will be stampled on the sideway near the rim (could be on either side of the tire) and will list the week and year of the tires date of manufacture.
You need to find the embossed stamp of "DOT" and you'll see a series of numbers and or letters. The last four digits are the week and year. For example, you may see "2802". This stands for the 28th week of 2002. The first two numbers will never be more than 52.

Please note, especially for RV's and trailers that aren't full timers. Any tire that sits a lot and is over 5 years of age is much more likely to have a belt seperation or blow out. You just have to realize that tires wear out, wether they are being used or not. If you budget a little each year, at the end of 5 years you can replace your tires for safety and piece of mind.

The most dangerous tires are the ones with full tread depth and over 5 years of age. The full tread depth and great looking condition is what often makes people assume the tires are in great working condition, but in actuality are a time bomb.

I just bought a 30' travel trailer and I am amazed at how "cheap" some things put on RV's are, regardless of the RV's cost. The two most notorious culprits are tires and mattresses.
I bet prisons have better mattresses than whats in a new RV!!

Cheers,
George