(BTW I am aware of the various "issues" concerning Carlisles, Marathons, and ST vs LT, having read many tire threads here over the years. Moving right along then-- :)My 2002 built OEM Goodyear Marathons (marked made in Canada) have just been replaced with Carlisles (marked made in China) built in 2014, and I have noted some differences in their "plies" as marked on the tires. Perhaps some of the experts here can explain it all. Thanks.Both are ST225/75R15 "For Trailer service only" The Marathons are Load range C and the Carlisles are Load range D. They show the weight ratings 2150 at 50psi and 2540 at 65psi, so that is clear.If it matters, here is another set of markings:Marathons- C11L DOT PDHH MROR 2602Carlisles- AQ29 DOT AQHH 2114Now the plies as marked on the tires: Marathons- Tread 5 plies 2 Poly cord + 2 steel cord + 1 nylon cordSidewall 2 plies poly cordCarlisle RH- Tread 4 plies 2 poly + 2 steel Sidewall 2 plies polyIn the recent thread about Carlisle RHs ISTR it was posted that they have a nylon cap or whatever, unlike the older Carlisles, but I am unclear on that. If they have nylon now, why isn't that marked like on the Marathons?Here is the Carlisle blurb on that. Mine are the Duratrail technology Radial Trail RHhttp://www.carlisletransportationproducts.com/product/tires/trailers-toy-haulers-towablesOK different topic, but I don't want two threads. For weight carrying, I only need Cs at 50 PSI, but now I have these Ds carrying the same weights. I know my truck tires have "adjustable" PSIs based on the load they carry up to a max rating.What about the STs? Do I pump the Ds to 65 or go with something less since they will not be "loaded" fully? Thanks.

In the recent thread about Carlisle RHs ISTR it was posted that they have a nylon cap or whatever, unlike the older Carlisles, but I am unclear on that. If they have nylon now, why isn't that marked like on the Marathons? Carlisle sells 5 different ST tires according to their website. Sport Trail LH Radial Trail RH Sport Trail Ultra Sport Radial USA Trail are you sure your tires say Carlisle Radial Trail RH ? OK different topic, but I don't want two threads. For weight carrying, I only need Cs at 50 PSI, but now I have these Ds carrying the same weights. I know my truck tires have "adjustable" PSIs based on the load they carry up to a max rating.What about the STs? Do I pump the Ds to 65 or go with something less since they will not be "loaded" fully? Thanks. you have two things going here. 1. The advantage of the D tire comes only at those higher pressures. 2. Carlisle says;-Maintain air pressure at the maximum PSI recommended on the tire sidewall. The Warranty is void if the tire or wheel fails due to damage from improper inflation pressures, exceeding the maximum speed limit, or overloading the tire beyond the maximum load capacity stated on the sidewall. Protect that new tire warranty and run them at 65 psi if the wheels are rated for those higher pressures.

Thanks guys. Ok I will run them at 65 lbs even though they will not be "worked" to that level of weight carrying. I was worried about the middle of the tread wearing from "over-inflation" and maybe the trailer being bounced too much back there.Yes, I have the "Radial Trail RH" tires and the "plies" are as marked on the tire is as stated in the OP. The 12 year old Marathons lasted this long because they were mostly out of the sun and only had about 10K miles on them. However they did have a couple of flats from nails/screws and one with a sharp rock that needed a patch, so one of those repaired ones sort of disintegrated the other day. People were passing me beeping and pointing, so that was my clue! Pieces of tire going from my trailer as seen from the driver's side mirror! Luckily I got to a road-side turn off spot before the wheel rim was damaged. Saved by Good Sam since I didn't feel like changing the tire with my spare (which I could have with a lot of work) and I have paid up to Good Sam over the years so I thought I would just get some of my money's worth. :) (Thanks, Mill Bay Towing) Anyway, after that little episode, I got all new tires figuring my luck had run out on those old ones! (Instead of getting just one new one) It turned out that local shops' availability and prices left me no choice but these Carlisles. (at KalTire) I figure I can ignore the usual "issues" on that brand because of the low mileage they will ever get.

BFL13 wrote:Thanks guys. Ok I will run them at 65 lbs even though they will not be "worked" to that level of weight carrying. I was worried about the middle of the tread wearing from "over-inflation" and maybe the trailer being bounced too much back there.Yes, I have the "Radial Trail RH" tires and the "plies" are as marked on the tire is as stated in the OP. The 12 year old Marathons lasted this long because they were mostly out of the sun and only had about 10K miles on them. However they did have a couple of flats from nails/screws and one with a sharp rock that needed a patch, so one of those repaired ones sort of disintegrated the other day. People were passing me beeping and pointing, so that was my clue! Pieces of tire going from my trailer as seen from the driver's side mirror! Luckily I got to a road-side turn off spot before the wheel rim was damaged. Saved by Good Sam since I didn't feel like changing the tire with my spare (which I could have with a lot of work) and I have paid up to Good Sam over the years so I thought I would just get some of my money's worth. :) (Thanks, Mill Bay Towing) Anyway, after that little episode, I got all new tires figuring my luck had run out on those old ones! (Instead of getting just one new one) It turned out that local shops' availability and prices left me no choice but these Carlisles. (at KalTire) I figure I can ignore the usual "issues" on that brand because of the low mileage they will ever get.At this point there are not any issues on the NEW Carlisle RH. FYI-The old tires were Carlisle Radial Trail. The NEW tires are signified by the "RH" designation after the name. The tread design is similar too. They improved the tire but did not purchase new molds for the new design. If you go here it looks like subtle tread pattern differences-ClickySome of the images are of the old tire-some are the NEW tire.

Thanks. Mine say on the sidewall markings that they have "Duratrail Technology" and are RH, so no doubt they are the best ever! :) Anyway I wonder about the "4 plies" instead of the "5 plies" for the tread like on the old Marathons (Never mind that being Load Range D, everybody calls them "8 ply" :) ) Of course then there is "belts" vs "plies" Way too complicated!

ST Tire "Plies" Question and a PSI Question | Good Sam Community

BFL13
Explorer II
Feb 27, 2015
Thanks. Mine say on the sidewall markings that they have "Duratrail Technology" and are RH, so no doubt they are the best ever! :)

Anyway I wonder about the "4 plies" instead of the "5 plies" for the tread like on the old Marathons (Never mind that being Load Range D, everybody calls them "8 ply" :) ) Of course then there is "belts" vs "plies" Way too complicated!
CKNSLS
Explorer
Feb 27, 2015
BFL13 wrote:
Thanks guys. Ok I will run them at 65 lbs even though they will not be "worked" to that level of weight carrying. I was worried about the middle of the tread wearing from "over-inflation" and maybe the trailer being bounced too much back there.

Yes, I have the "Radial Trail RH" tires and the "plies" are as marked on the tire is as stated in the OP.

The 12 year old Marathons lasted this long because they were mostly out of the sun and only had about 10K miles on them. However they did have a couple of flats from nails/screws and one with a sharp rock that needed a patch, so one of those repaired ones sort of disintegrated the other day. People were passing me beeping and pointing, so that was my clue! Pieces of tire going from my trailer as seen from the driver's side mirror! Luckily I got to a road-side turn off spot before the wheel rim was damaged.

Saved by Good Sam since I didn't feel like changing the tire with my spare (which I could have with a lot of work) and I have paid up to Good Sam over the years so I thought I would just get some of my money's worth. :) (Thanks, Mill Bay Towing)

Anyway, after that little episode, I got all new tires figuring my luck had run out on those old ones! (Instead of getting just one new one) It turned out that local shops' availability and prices left me no choice but these Carlisles. (at KalTire) I figure I can ignore the usual "issues" on that brand because of the low mileage they will ever get.

At this point there are not any issues on the NEW Carlisle RH. FYI-The old tires were Carlisle Radial Trail. The NEW tires are signified by the "RH" designation after the name. The tread design is similar too. They improved the tire but did not purchase new molds for the new design. If you go here it looks like subtle tread pattern differences-Clicky

Some of the images are of the old tire-some are the NEW tire.
BFL13
Explorer II
Feb 27, 2015
Thanks guys. Ok I will run them at 65 lbs even though they will not be "worked" to that level of weight carrying. I was worried about the middle of the tread wearing from "over-inflation" and maybe the trailer being bounced too much back there.

Yes, I have the "Radial Trail RH" tires and the "plies" are as marked on the tire is as stated in the OP.

The 12 year old Marathons lasted this long because they were mostly out of the sun and only had about 10K miles on them. However they did have a couple of flats from nails/screws and one with a sharp rock that needed a patch, so one of those repaired ones sort of disintegrated the other day. People were passing me beeping and pointing, so that was my clue! Pieces of tire going from my trailer as seen from the driver's side mirror! Luckily I got to a road-side turn off spot before the wheel rim was damaged.

Saved by Good Sam since I didn't feel like changing the tire with my spare (which I could have with a lot of work) and I have paid up to Good Sam over the years so I thought I would just get some of my money's worth. :) (Thanks, Mill Bay Towing)

Anyway, after that little episode, I got all new tires figuring my luck had run out on those old ones! (Instead of getting just one new one) It turned out that local shops' availability and prices left me no choice but these Carlisles. (at KalTire) I figure I can ignore the usual "issues" on that brand because of the low mileage they will ever get.
JIMNLIN
Explorer III
Feb 27, 2015
In the recent thread about Carlisle RHs ISTR it was posted that they have a nylon cap or whatever, unlike the older Carlisles, but I am unclear on that. If they have nylon now, why isn't that marked like on the Marathons?

Carlisle sells 5 different ST tires according to their website.
Sport Trail LH
Radial Trail RH
Sport Trail
Ultra Sport Radial
USA Trail
are you sure your tires say Carlisle Radial Trail RH ?

OK different topic, but I don't want two threads. For weight carrying, I only need Cs at 50 PSI, but now I have these Ds carrying the same weights. I know my truck tires have "adjustable" PSIs based on the load they carry up to a max rating.

What about the STs? Do I pump the Ds to 65 or go with something less since they will not be "loaded" fully? Thanks.

you have two things going here.
1. The advantage of the D tire comes only at those higher pressures.

2. Carlisle says;
-Maintain air pressure at the maximum PSI recommended on the tire sidewall.

The Warranty is void if the tire or wheel fails due to damage from improper inflation pressures, exceeding the maximum speed limit, or overloading the tire beyond the maximum load capacity stated on the sidewall.

Protect that new tire warranty and run them at 65 psi if the wheels are rated for those higher pressures.
jaycocamprs
Explorer
Feb 26, 2015
I would run the D's at 65psi.

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