LT tires

eagleeye · November 16, 2006

the aluminum stock wheels on my 2005 GMC sierra 1500 quad cab came with General Ameritrac P245/70R17 tires. We pulled a travel trailer 8500 miles this year that weighs about 6500 lbs loaded and I noticed the rear tires wore down about 1/4" and the front tire wore uneven more on the outsidetread area, I kept the tire pressure at 44 psi. Would a shift to LT rated tires help and are the aluminum wheels designed to handle LT tires. I'm still under warranty and don't want to void it by using tires not designed for these wheels.

95Sierra2500 · November 16, 2006

I don't know why you've got P tires on there anyway, since personally I think they're for cars. What's the max pressure rating on your tires? If you're towing that much weight, you should be running the max pressure when the tires are warm. As for voiding your warrenty, I highly doubt you'll do that by switching to a better tire (Load range E is a MUST with the weight you're towing, preferably a 10-ply).

chanswork · November 17, 2006

I personally think there is bad engineering with the gm vehicles running 245/70/17 tires. I've noticed alot of the one's I get from my friend that lifts trucks...they all wear uneven on the front end. The outer edges are always worn with only a few thousand miles on them.

I don't think it's the tire problem, it should be GM's problem in design. With the bigger 265/70/17 tires some upgraded models have show a little less on the edge wearing but it still occurs. The only way I see this problem stop is when I upgrade to 275/55/20 tires. With a really wide tire, the edges seem to stop wearing out prematurely. Does any GM-Techs or Enthusiasts know the reason for this? Even when the tires are perfectly balanced, aligned and pressurized...still does it.

As far as LT tires vs Passenger tires, the LT's hold alot more air and are much stronger for towing purposes. You can definately go to a bigger 265/70/17 LT tire if you wish. This will reduce the premature wearing of the edges and also handle weight better than the Passenger 245/70/17 tire. The only downside to this is the ride quality on a LT tire is not as good as a Passenger tire, much harsher.....probably the reason GM uses Passenger tires instead of LT on light duty trucks. Going to a 265/70/17 LT tire will not affect warranty, that tire size comes standard on upgraded models from GM.

eagleeye · November 17, 2006

I don't know why you've got P tires on there anyway, since personally I think they're for cars. What's the max pressure rating on your tires? If you're towing that much weight, you should be running the max pressure when the tires are warm. As for voiding your warrenty, I highly doubt you'll do that by switching to a better tire (Load range E is a MUST with the weight you're towing, preferably a 10-ply).

<{POST_SNAPBACK}>

Max pressure for these tire is 44 psi. The truck is rated to pull 7700 lbs of trailer weight and 770 lbs of tonque weight.

eagleeye · November 17, 2006

I personally think there is bad engineering with the gm vehicles running 245/70/17 tires. I've noticed alot of the one's I get from my friend that lifts trucks...they all wear uneven on the front end. The outer edges are always worn with only a few thousand miles on them.

I don't think it's the tire problem, it should be GM's problem in design. With the bigger 265/70/17 tires some upgraded models have show a little less on the edge wearing but it still occurs. The only way I see this problem stop is when I upgrade to 275/55/20 tires. With a really wide tire, the edges seem to stop wearing out prematurely. Does any GM-Techs or Enthusiasts know the reason for this? Even when the tires are perfectly balanced, aligned and pressurized...still does it.

As far as LT tires vs Passenger tires, the LT's hold alot more air and are much stronger for towing purposes. You can definately go to a bigger 265/70/17 LT tire if you wish. This will reduce the premature wearing of the edges and also handle weight better than the Passenger 245/70/17 tire. The only downside to this is the ride quality on a LT tire is not as good as a Passenger tire, much harsher.....probably the reason GM uses Passenger tires instead of LT on light duty trucks. Going to a 265/70/17 LT tire will not affect warranty, that tire size comes standard on upgraded models from GM.

<{POST_SNAPBACK}>

Thanks the LT265/70/17 information was what I was looking for. MMCM,USN,RET

C & A s Dad · November 17, 2006

Bill, I was in almost the same situation. Pulling a 6500 lb/900 lb tongue wt camper with a Yukon XL 1500 with 4.10 gears. I researched the LT and P thing for too long before I made my decesion. I tow about 6 to 8 times a year and 4 to 6 of those trips are 35 miles or less one way. I will make 1 to 2 trips a year of 300 to 400 miles one way. I could not give up the ride quality and went with Bridgestone Dueler HL Alenza's. Their wt rating (2,469lbs)is a little higher than other P tires. I have towed twice with them with one of the trips being 200 miles one way. They are so far supperior to the Firestone Wilderness LE s that I took off that I could not believe it. I run them at 42 in the rear and 40 in the front. I also have an Equal i zer Weitght Distribuition hitch and Air Lift Springs inserted in my rear coils.

I am assuming you are using a weight dist hitch unless of course you are pulling a fifth wheel.

I think it comes down to how much time the truck spends towing vs how much it is used for normal transportation. I also read on some RV forums that the 1500 series wheels in some cases are not designed for the higher PSI LT tires. I really cannot comment much on this but there is some who say they are not designed for these higher PSI s.

Do your research and talk to a couple of good tire shops that you trust.

Dave in Mpls · November 17, 2006

All good advice above.

I will say, if you decide to upgrade to a 265/70/17 LT, your tire choices will be severely limited. I am in the same boat right now looking at replacing the tires on my '04 Z71 Suburban with the stock size (265/70/17) and am totally unimpressed with the options for a LT tire, particularily in a C load rating.

Your mileage may vary!

Let us know what you decide to go with.

Frank Sub · November 17, 2006

Hi C & A s Dad--My Suburban and trailer are about the same as yours. I am currently running the originial Firestone LE P265/70R16. Would be interested in any specific items you noticed improved with the Bridgestone Dueler HL Alenza.--Frank Sub

C & A s Dad · November 17, 2006

Frank, my Firestones had 47K on them but they were somewhat "cupped" on the inside. The truck was not out of alignement and they had been rotated but as you know there is a lot of conversation about these trucks cupping tires. The tread depth was great but they had become very noisy even to the point that I thought I had a bearing going out. The Duelers are so quiet I cannot believe the difference they made. It made my truck seem new again as far as ride and noise.

As far as towing, It is hard to tell because I was towing on the Natchez Trace which is an extremely smooth road. However, it was simply more stable and just "sat in the road" so much better. After about 100 miles on the Trace that day, I told my wife that I could drive all day with the way it was pulling. It was also raining like crazy but all felt really good.

I would not tell you to throw away a set of Firestones if they are still in good shape, but I would tell you to look closely at the Dueler HL Alenza when you do need to replace the Firestones.

chanswork · November 17, 2006

There are alot of options available for LT265/70/17 tires. Ford and Dodge both have an OEM LT265/70/17. Ford uses a Pirelli and Dodge uses Michelins and both are load range E. Go to tirerack.com and you can see what's out there and read some of the reviews their customers have posted.

eagleeye · November 18, 2006

Bill, I was in almost the same situation. Pulling a 6500 lb/900 lb tongue wt camper with a Yukon XL 1500 with 4.10 gears. I researched the LT and P thing for too long before I made my decesion. I tow about 6 to 8 times a year and 4 to 6 of those trips are 35 miles or less one way. I will make 1 to 2 trips a year of 300 to 400 miles one way. I could not give up the ride quality and went with Bridgestone Dueler HL Alenza's. Their wt rating (2,469lbs)is a little higher than other P tires. I have towed twice with them with one of the trips being 200 miles one way. They are so far supperior to the Firestone Wilderness LE s that I took off that I could not believe it. I run them at 42 in the rear and 40 in the front. I also have an Equal i zer Weitght Distribuition hitch and Air Lift Springs inserted in my rear coils.

I am assuming you are using a weight dist hitch unless of course you are pulling a fifth wheel.

I think it comes down to how much time the truck spends towing vs how much it is used for normal transportation. I also read on some RV forums that the 1500 series wheels in some cases are not designed for the higher PSI LT tires. I really cannot comment much on this but there is some who say they are not designed for these higher PSI s.

Do your research and talk to a couple of good tire shops that you trust.

<{POST_SNAPBACK}>

Thanks Trey, I do use a weight dist hitch to pull our 2003 Airstream 25 Safari. Have read up on Timbren spring kits and air lifts but thought maybe all that was needed was LT rated tires. I'll check out the Bridgestone Duelers as I'd hate to ruin the ride quality of the GMC.