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Towing tire question

Rhombus

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All, I just purchased a 2020 Solaire 249 RBS. Will be pulling with my Ecodiesel using. ProPride 3P hitch. Empty weight is ~5500 lbs and gross is ~7400 lbs.
I’ve run Cooper ATP’s for year. https://www.discounttire.com/buy-tires/cooper-discoverer-atp-ii/p/88138 these have always been great tires, standard load range. I’m considering upgrading to Cooper AT3 XLT’S, which are old range E1. I know these will not add to the max loads for my truck, but I do have seceral questions please:

- are these overkill? I.e., will the ATP’s be sufficient with my setup?
- if I DO go with these, will they beat me to death?

appreciate any thoughts. Thanks.
 

Nsleone

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All, I just purchased a 2020 Solaire 249 RBS. Will be pulling with my Ecodiesel using. ProPride 3P hitch. Empty weight is ~5500 lbs and gross is ~7400 lbs.
I’ve run Cooper ATP’s for year. https://www.discounttire.com/buy-tires/cooper-discoverer-atp-ii/p/88138 these have always been great tires, standard load range. I’m considering upgrading to Cooper AT3 XLT’S, which are old range E1. I know these will not add to the max loads for my truck, but I do have seceral questions please:

- are these overkill? I.e., will the ATP’s be sufficient with my setup?
- if I DO go with these, will they beat me to death?

appreciate any thoughts. Thanks.
You’ll be fine on the ATP’s, they have a load index of 115 which is 2679 pounds per tire, plenty of weight carrying capacity. It never hurts to improve safety but I’d say it’s not necessary :)
 

Rhombus

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You’ll be fine on the ATP’s, they have a load index of 115 which is 2679 pounds per tire, plenty of weight carrying capacity. It never hurts to improve safety but I’d say it’s not necessary :)
Thanks very much
 

IvoryHemi

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The load carrying capacity is not the issue with the SL tire, it’s the soft sidewalls.

Towing a tall, long box such as your 249RBS, you will want a stiffer sidewall to help with side to side motions.

Absolutely skip the ATP.

Yes ‘E’ will be a stiff tire, I find ‘XL’ is a good compromise.
 

Nsleone

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The load carrying capacity is not the issue with the SL tire, it’s the soft sidewalls.

Towing a tall, long box such as your 249RBS, you will want a stiffer sidewall to help with side to side motions.

Absolutely skip the ATP.

Yes ‘E’ will be a stiff tire, I find ‘XL’ is a good compromise.

Wouldn’t the load rating drop if the sidewall was to soft? I’m still on the factory Bridgestone’s which have a 113 rating, not sure on the category it doesn’t say on tire rack.
 

IvoryHemi

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Wouldn’t the load rating drop if the sidewall was to soft? I’m still on the factory Bridgestone’s which have a 113 rating, not sure on the category it doesn’t say on tire rack.

The factory Bridgestone’s are SL. Load capacity is fine, but it’s not only about weight when towing.

SL tires are ok for say a 7k open car trailer, where is there is no wind resistance. A travel trailer that is a 11’ tall, 28’ long box has significant wind sail that will create side to side rocking motion in the tow vehicle. A stiffer sidewall will help that
 

Pertzbro

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You can always lower the air pressure when not towing to a more normal 35-40psi and that should help with how stiff they ride.
 

AngelPhoenix

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You can always lower the air pressure when not towing to a more normal 35-40psi and that should help with how stiff they ride.
I thought/heard that too but further research suggests that's not a good idea. Those tires are built/designed to run at high PSI, running them at 2/3rd or half of that will mess with them. I mean, imagine running your P-rated tires at like 20 PSI. It's not an exact equivalent comparison but gives you some idea. You'll get less miles out of them, could throw them out of round over time, etc.

There's probably people that do this without issues, but also probably others that have had issues. If you're towing frequently enough and heavy enough to go for LT tires, you're probably not daily driving your truck as much as someone who wants to stay away from LT tires entirely, if at all possible (me).
 

Lpsouth1978

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I thought/heard that too but further research suggests that's not a good idea. Those tires are built/designed to run at high PSI, running them at 2/3rd or half of that will mess with them. I mean, imagine running your P-rated tires at like 20 PSI. It's not an exact equivalent comparison but gives you some idea. You'll get less miles out of them, could throw them out of round over time, etc.

There's probably people that do this without issues, but also probably others that have had issues. If you're towing frequently enough and heavy enough to go for LT tires, you're probably not daily driving your truck as much as someone who wants to stay away from LT tires entirely, if at all possible (me).
Even Discount Tire recommends inflating E rated tires to the pressure stated on the door jam of the vehicle. It is my understanding that just because an E rated tire has a MAX of 80psi, it is not necessary to run it at that all the time, not even recommended to do so. I keep My tires at 45-50psi for daily use and increase the pressure to 60-65psi when towing the TT. I did not notice a significant change to ride quality at this psi (my truck is primarily my daily driver with some TT pulling).
 

AngelPhoenix

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Even Discount Tire recommends inflating E rated tires to the pressure stated on the door jam of the vehicle. It is my understanding that just because an E rated tire has a MAX of 80psi, it is not necessary to run it at that all the time, not even recommended to do so. I keep My tires at 45-50psi for daily use and increase the pressure to 60-65psi when towing the TT. I did not notice a significant change to ride quality at this psi (my truck is primarily my daily driver with some TT pulling).
Maybe if they were the same size as the tires they're replacing, but E's are almost always bigger than stock (unless it came with E's, which no 1500's do these).

And I wasn't saying you should run them at max PSI, but running them at half that seems like it would be as bad as running most any tire at half it's max. I'm sure there's more nuance here that's beyond me. And the make and type of tire (H/T, A/T, etc) probably factors in too.
 

RRSBighorn

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I have a 27' tandem TT that I pull, 7k GVWR, I am usually around 6k lbs loaded. I have had issues with slight trailer sway since I got my 2019 Ram. I have made many changes to trailer suspension, setting up Wt distribution correctly, and put new D rated trailer tires on, original equipment was C rated, which matched the 3.5k axles fine. I added the D tires to get stiffer sidewalls hoping to control some of the sway. I took a 3k trip to Yellowstone last Aug and the truck was better, but a little wind and I had to slow it down, didn't like how the setup tracked, kind of an unsettling feeling, more of a squirminess feel than a sway issue. Anyway, about the pressure you should use, here's what Goodyear says about what pressures to use for their trailer tires. I have a 205/75R15, (see attached) and according to this I could run 50 psi (same as the C tires) to get 1820 lb load rating per wheel. I didn't see this before my trip as I ran 65 psi on someone's recommendation.

So now I'm looking at replacing my Bridgestone Dueller 275/55R20 113 as I feel the sidewalls are too soft. I didn't want a D or E rated tire, because I only tow ~3k miles a year, so the Continental Terrain Contact H/t 117H XL (50psi max) are 1 step above SL load (44psi max) metric tires but not as stiff as LT C-E ply rated tires. I don't drive offroad didn't want All Terrain and wanted highway tires that were quiet, but wanted stiffer sidewalls for towing.
The Continental TerrainContact H/T is a highway tire. This means that it is designed with on-road stability and dynamics in mind, but also longer treadlife, and high levels of comfort. Thanks to the super-strong casing, this model can also be used for hauling heavy payloads or towing large trailers.
See Review here: https://www.tirede ets.com/continental-terraincontact-h-t-review/

I will play with tire pressures, but I don't think I will keep the truck and trailer tires pressured to their maximum, I will try to find the right balance of ride and stabiliy. Obviously when not trailering, I will probably have less pressure in the truck tires. I assuming that the pressure vs load rating is probably similar on all tires, I'm going to see if Continental has some chart like the Goodyear attached.
 

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Bt10

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In another thread, someone posted a formula on a tire site link that helps you calculate the optimum psi with a given load. For an E range tire on a 1500, use the formula to find the pressure that is optimal. The door sticker will work fine as well; that's why the tire shops recommend it. Maybe I'll try to find it, sometime, maybe... :giggle:
 

RRSBighorn

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In another thread, someone posted a formula on a tire site link that helps you calculate the optimum psi with a given load. For an E range tire on a 1500, use the formula to find the pressure that is optimal. The door sticker will work fine as well; that's why the tire shops recommend it. Maybe I'll try to find it, sometime, maybe... :giggle:
I couldn't find any info on Continental, Discount tire websites, or Google search, there's not a lot out the about changing OEM tires to a higher Index/range and tire pressure. But I finally found this on an Airstream Forum, it seems that Discount Tire uses this chart when switching load or index ratings to higher than OEM. I couldn't find it on their current website, but this attachment may help someone for future reference.
 

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Pertzbro

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the MAX PSI is for MAX weight limit. It is not the suggested inflation amount but actually the maximum amount of air that tire can hold for maximum weight rating.
 

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