Replacing 2500 oem GY 20" Tires for better weight rating...

cjackg · October 1, 2014

I am considering replacing the oem Goodyear LT265/60R20E tires on my Silverado 2500HD 4x4 in order to increase the weight rating to 3750 and maybe get a better ride with less vibration. The only Michelin tires I could find that might fit are the LTX 275/65R20 MS2 or AT2.

There seems to be plenty of room underneath for the bigger tires but I sure would like to hear from someone that has "been there and done that"!

Is this tire upgrade likely to require lifting the truck? Any help will be appreciated!

ifixedit · October 1, 2014

I sell large commercial truck tires for a living and would love to help you out with some pickup tires but we stick with the big stuff. I did look up your original OEM size and it doesn't come up, but Goodyear like some other brands does have a habit of making a few odd sizes the others do not. The thinking is when you wear them out you can't find the size in another brand anywhere else forcing you to buy Goodyear's again. Are you sure if the Goodyear's you have now aren't 275/60R20's?

In any case the difference in size between what you have now and what you want to put on is very close with the new ones maybe being only slightly larger. You are correct, going to the 275/65R20 the load capacity per tire is 3750 lbs., but what is a bit odd as well is the tires on your HD should have come stock 10 ply rated for the load capacity you want in the first place. It doesn't sound like you did, but sometimes people will put on lower rated (and less expensive) 6 or 8 ply rated tires just for the reason of giving a softer ride as the sidewall of the tire is softer, I don't recommend doing this though as it's a safety concern, you want 10 ply rated for sure.

Before you buy, I always recommend to my customers wanting to change from the OE size to bring the truck to the tire shop of your choice and have them mount one or two tires up, install them on the front steer axle in particular and check for clearance issues such as when turning tightly to make sure they do not contact the frame or rub the inner fender well, this is the only safe and sure way to know for sure if they will work, otherwise we're guessing. If the shop really wants to help you out and sell you tires, they should be willing to take the few extra minutes to do this for you. I think in your case you should be fine but best to check for sure.

If you do not have 10 ply rated tires on the truck now, it will probably ride a bit rougher with them, but Michelin is known for having a softer sidewall than other brands and are bought in many cases for their ride. Best bet don't buy any cheapies or the ride will for sure suffer. Usually the rule of thumb is the more flexible the sidewall the better the ride.

I hope this helps.

cjackg · October 1, 2014

Your comments are definitely helpful.... The oem tires are definitely LT265/60R20 Load Range E but the Max Load as shown on the sidewall is 3195 lbs at 80psi, which worries me pulling a 16000 lb Fifth Wheel. I have ordered the Michelins through CostCo and guess I will see how it goes....

ifixedit · October 2, 2014

Well, if they say load range "E" you at least do have 10 ply tires now as I would have expected on an HD. The 275/65 and 265/60 numbers are what's referred to as the aspect ratio of the tire, the height in relationship to the width of the tire. In this case one set of numbers slightly trades off for the other, so if I were to guess, your new size will be slightly taller (larger in diameter) and just a bit wider as well, height probably more noticeable than width, but should work in your case as even on my 03 Silverado there's all kinds of room in the wheel wells yet with the stock tires and wheels on it.

A couple of things: First I hope you are at least taking the tires somewhere to have them mounted and not doing it yourself as you want them properly balanced. Michelins are certainly not at give-away prices right now so you want them set up to perform at their best right off the get go. If you do decide to mount them yourself, Michelin as many other major brand tire manufacturers do, they mark the sidewall with a yellow dot (but some times although very rarely, with a white dot instead) and red dot. If by chance both a white and yellow dot appear on the tire, use the yellow dot. The yellow dot indicates the light point of the tire, you want to line the yellow dot up with the valve stem on the wheel which is the heavy point of the wheel. Don't worry about the red dot or any other colored dots. When you are towing go with what is caled for "Max" inflation PSI on the sidewall for both the front and rear tires, don't over-inflate or under-inflate. Being you are going to a larger in diameter size tire it's going to throw off your speedometer some, it saying 65 MPH and you may be actually going 70 MPH. I don't know on the newer trucks if it's possible but to correct this the speedometer needs to be re-calibrated to the new tire size, on large trucks this is common and is done via the computer. If this is possible on your truck all you need to know is how many revolutions per mile the tire is turning and this info is generally included in the given tire's specs.

Good luck with your project!

Big Whiskey · October 3, 2014

Your stock tires are 32.5" tall, while the new 275/65 tires will be 34.1" tall. That's a change of about 5%, so your speedometer will be off that much as well. The new tires will only by 10mm wider than stock, which isn't much. As far as fitment goes, there are lots of guys running that size on 1500's with just a 2" level kit, so you should be fine on your 2500HD. You may need to crank your torsion bars just a couple turns, but nothing major.

cjackg · October 5, 2014

I am considering replacing the oem Goodyear LT265/60R20E tires on my Silverado 2500HD 4x4 in order to increase the weight rating to 3750 and maybe get a better ride with less vibration. The only Michelin tires I could find that might fit are the LTX 275/65R20 MS2 or AT2.

There seems to be plenty of room underneath for the bigger tires but I sure would like to hear from someone that has "been there and done that"!

Is this tire upgrade likely to require lifting the truck? Any help will be appreciated!

For anyone interested.... Costco installed a set of Michelin LTX 275/65R20 MS2 tires on my 2500HD today and they fit just fine with no clearance issues, changes or mods whatsoever. My Max weight rating jumped from 3195 to 3750lbs per tire and they ride even smoother than the oem GY tires. The only negative effect is I will probably need to have the Speedometer recalibrated and now my truck sits even higher than before!

http://www.gm-trucks.com/forums/gallery/image/10092-michelin03/

http://www.gm-trucks.com/forums/gallery/image/10093-michelinlabel/