"C" or "E" which one

[purman]

I'm hoping some Tundra people can help me out here. We have a Sequoia with 275 / 65 / 18 on it. We drive it as an everyday driver with the 4 kids, but use it to tow 3-5 thousand miles a year too. we put about 20,000 miles a year on it.

So the last time I put Yokohama geolanders on it in a "C" rating. I would like a "D" for towing but I can't find a "D" rated tire in that size that has tread that will be good in the snow. We live at 7000 feet and have snow in the winter and also take the kids to ski school for 2 months out of the year. So i need a good snow tire as well..

The "C" rated tire I have now seemed to work pretty well. I am a little reluctant to go to an "E" rated tire as the ride might be to stiff or hard.

So did I just get lucky with the "C" tires towing. Is the "E" rated to stiff for a 1/2 ton. Does anyone know of a "D" rated tire with snow tread in that size?
Thanks

[Steamy1]

I have E-rated Michelin Ice on our 2000 Land Cruiser, and E-rated Michelin A/S2 on the Tundra. I even have Michelin LT MS2 16" E-rated tires on the Bambi.

Very please with how they roll, and do not feel too stiff to me. I will always go with E rated tires.

[aftermath]

Jason,

I also drive an 08 Tundra and I am running a set of E Yokohamas. So far, so good and I did notice an ever so slight difference from the original tires. I like the ride and am glad I made the switch. I haven't experienced any negatives when pulling my Airstream and I do like the tread design as I also live in a snowy climate. They are quiet on the dry pavement too.

[rbs]

What pressure do you carry in the tires when not towing?

[Wabbiteer]

I went from Goodyear M/S C's to a set of load range D Michelins as take-offs from a gentleman who wanted mudder tires on his new Dodge. They had 3500 miles on them and I paid $90 each with mounting & balancing. Now, some seven years and 70,000 miles later I wish I hadn't, they beat the truck up pretty bad.

I ended up running them a long while under-inflated for our bad city streets since the ride is so harsh - they transmit a lot more punishment into that suspension that I can't afford to replace as easily as slapping tires on.

Alignment is harder to be happy with since they don't negotiate as delicately with the steering wheel. True, on smooth pavement at interstate speeds there is/was decidedly less wiggle but most of the luxury feel went out of them after they passed 30,000 miles wear.

In cold weather it takes an extra long time for them to warm up so any <15 minute interstate trips its a noisy clunking ride. The first three winters they did okay in snow, the last three I get more and more nervous about trusting them, something about a stiff sidewall erasing feedback of when its turning into a sled.

Anyhow - Load 'C' tires already have the stiffness and carrying capability most of our standard pick-ups are designed around and I am looking forward to going back to 'C' range tires... Just wish I'd bought last year at this time since everything has gone up $50 each since. If the vehicle was designed around D's or E's go for it, if it came with C's remember they built trade-offs into it up front.

[dkottum]

There is a trade-off when changing to stiffer-sidewall tires. Smooth ride is sacrificed for towing stability (less side-to-side movement of the tire, therefore noticeable sway control).

doug k

[Steamy1]

Originally Posted by rbs

What pressure do you carry in the tires when not towing?

I keep it at 50 psi front and back on the Tundra; 80 psi on the Bambi, though keeping in mind that I have the correctly rated wheels and metal high pressure valve stems.

[purman]

So we have a yeah and a neah, So far I think I might stay with the "C" anyone else running "E" rating on an every day driver?

[SteveH]

I don't see the benefit of using an "E" rated tire on a 1/2 ton vehicle of any kind because the suspension/axle/frame, etc., are not rated to carry as much weight as the tires. Just my opinion.

[dkottum]

SteveH, the benefit of stiffer sidewalls on 1/2 ton is less side-to-side movement when towing. It's a benefit you will feel immediately compared to the standard passenger rated tires.

doug k

[SteveH]

Originally Posted by dkottum

SteveH, the benefit of stiffer sidewalls on 1/2 ton is less side-to-side movement when towing. It's a benefit you will feel immediately compared to the standard passenger rated tires.

doug k

Doug, Yes I can understand the stability aspect, but not the extreem of going ot an "E" rated tire. I would think a "C", or maybe a "D" rated tire would be more than adequate.

I run "E" rated tires on my 3/4 ton, and see very little difference in stability between 65 lbs of pressure (the max pressure of a "D" rated tire) and 80 lbs of pressure, max for the "E".

Additionally, are the wheels that a 1/2 ton is equipped with rated for 80 pounds of pressure?

If you actually NEED the weight carrying capacity of an "E" rated tire with the 1/2 ton truck, I would think you are overloading everything else on the truck.

Not trying to be argumentative here, just stating my thoughts.

[Protagonist]

Originally Posted by SteveH

I run "E" rated tires on my 3/4 ton, and see very little difference in stability between 65 lbs of pressure (the max pressure of a "D" rated tire) and 80 lbs of pressure, max for the "E".

Are you saying that you actually inflate your tires to 65psi with D-rated tires, and 80psi for E-rated tires?

That's not how it should work. No matter what the maximum pressure is for a tire, go by what the vehicle owner's manual says for tire inflation. I very much doubt that a 3/4-ton pickup's owner's manual would recommend anything higher than about 40psi even fully loaded. By inflating the tires to the maximum listed on the tire regardless of the weight of the vehicle, you lose a lot of traction because only the center portion of the tread is making good contact with the road, not the full tread width.

Using my own Interstate as an example, the tires have a maximum pressure of 80 psi listed on the tire, but the owner's manual calls for a maximum of 61psi. I do not exceed 61psi actual inflation, and even after driving 520 miles straight, stopping only for fuel, the tires were still cooler to the touch than was the asphalt they rested on.

My Interstate has a GVWR of 11,030 pounds. Inflating the tires to 61psi, that means that the load of the vehicle is distributed over 180 square inches of tread (6 tires, average of 30 square inches per tire). If I inflated to 80psi, the weight of the vehicle would then be distributed over just 138 square inches of tread, or just 23 square inches per tire. Traction would be cut by 24%. Big difference!

[SteveH]

Originally Posted by Protagonist

Are you saying that you actually inflate your tires to 65psi with D-rated tires, and 80psi for E-rated tires?

That's not how it should work. No matter what the maximum pressure is for a tire, go by what the vehicle owner's manual says for tire inflation. I very much doubt that a 3/4-ton pickup's owner's manual would recommend anything higher than about 40psi even fully loaded. By inflating the tires to the maximum listed on the tire regardless of the weight of the vehicle, you lose a lot of traction because only the center portion of the tread is making good contact with the road, not the full tread width.

Using my own Interstate as an example, the tires have a maximum pressure of 80 psi listed on the tire, but the owner's manual calls for a maximum of 61psi. I do not exceed 61psi actual inflation, and even after driving 520 miles straight, stopping only for fuel, the tires were still cooler to the touch than was the asphalt they rested on.

My Interstate has a GVWR of 11,030 pounds. Inflating the tires to 61psi, that means that the load of the vehicle is distributed over 180 square inches of tread (6 tires, average of 30 square inches per tire). If I inflated to 80psi, the weight of the vehicle would then be distributed over just 138 square inches of tread, or just 23 square inches per tire. Traction would be cut by 24%. Big difference!

Yes, I'm saying I inflate my rear truck tires to 80 PSI. The sticker on the door recommends 65 PSI front, 75 PSI rear and that is what they compute to be able to carry it's rated weight. I go 70 front, and when towing 80 rear because it's hot here, and almost any time we go somewhere, we travel long distances at what many people would consider high speed.

I know that heat is a tire's worst enemy, and hot weather, heavy load, and high speed is combination that will distroy a good tire that is underinflated.

I also run my trailer tires (225, 75X16 E) at 75 PSI for the same reason.

No one can say what will happen tomorrow, but to date I have never had a trailer or tow vehicle tire failure that was not due to a puncture.

[Protagonist]

Originally Posted by SteveH

The sticker on the door recommends 65 PSI front, 75 PSI rear and that is what they compute to be able to carry it's rated weight.

I am surprised. I wouldn't have thought it was that high. Not doubting you, just saying. If your vehicle's data plate calls for 65/75, then an E-rated tire really is the minimum you should use, because the tire maximum should be at least as high, if not higher, than the vehicle-recommended maximum. Don't know about the 5psi overinflation you use, but other than that, sounds like you've got it worked out just right.

[SteveH]

The GVWR of the truck is 9200 lbs, and the RAWR is 6400 pounds. It's an '08 GMC 3/4 ton, 4X4, crew cab, Duramax Diesel/Allison drive train.

I like to go a little higher with air pressure than needed when towing for a little added stability. I know lower pressure in the tires would carry the weight, in theory, but that's what I do, haven't had problems, and want to keep it that way.