1 New tire VS 3 older tires

[TMax]

Guys,

I had to replace one of my tires due to road damage while the other three tires have another 15K left on them. They've been about 40K so far. Anyway, am I going to screw up a diff or a tranfer case because the new tire has more tread depth than the other three? I moved the new tire to the rear to lessen wear thinking that the front end is tougher on tires considering the weight of the mighty Cummins. Anybody see an impending problem here with the different circumferences?

Thanks!

TMax

 

[jgillott]

Do you have a limited slip or locker in the rear?

 

[TMax]

I just have the LS no locker.

 

[TMax]

Andres,

I think I would have a problem the other way since I have larger tires on there than stock.

 

[jgillott]

My gut reaction would be to run that new tire on the front or buy a second new one to match the one you just bought and mount them on the front or rear as a matched set. I'd be personally a little uneasy about the LS Diff over time with that tire on the rear. It may never cause a problem, but I worry about that kind of stuff.

 

[DEM123]

Put your spare on, probably brand new and never been down!!

 

[DHess]

I maybe old school but I go with the theory that tires on the same axle should be the same HEIGHT - and on a 4x4 all four tires the same HEIGHT. Tires should turn the same nimber of revolutions over a given distance. I think the tire dealer should have made you a deal on two tires and an even better deal on four.



Dave

 

[TMax]

Dave,

I agree with you except for the fact that I really wanted to see what kind of mileage I could get out of these tires. They are wearing like iron and I hate to cut them short! Plus I didn't have the $$ for new treads right now. There's that... . I may have to bite the bullet and get at least one more for the rear to match the set on the axle.

 

[Road Dog]

You can get a new tire shaved to match the others or you can buy a used tire if it's common. The different diameter shouldn't matter on the front with it's open diff and won't affect the handling either. I ran a 32" and 30" spare on the front for 500km (with a trailer) with no issues. That's what happens when you lose a tire far from home.

 

[MechanicMike]

I always like replacing 2 tires in a case like this. That way the 2 new tires should be installed on the same axle which would prevent any premature wear of drivetrain components and drivability problems such as a pull. You will still be able to rotate em to ensure you get the most service out of the newer tires. Hope this helps



Mike

 

[TMax]

Went over to Discount to see if they would sell me another tire to match the new one and they would only come off retail only slightly. I am going to try a different store before giving up. I bought them for $275 per tire a couple years ago and then these guys are telling me some story about a price increase that Cooper had some months ago and want $347 each. They prorated the defective tire down to $229. I suggested they give me the same deal and I would buy a matching tire so I didn't screw up the diff. He said I didn't have to worry about that. Hmmmm. Peace of mind dictates my doing more shopping.

 

[HHhuntitall]

TMax, if you have Limited slip, don't do it, unless you do it on the front. If in 4x4, on loose ground, you can get away with it. But on the rear, it will generate heat, and premature wear on the diff. While 1/2 of tread(1/4 per side) doesn't seem like much, it shortens the roll out quite a bit, making one tire turn 3-4 turns more per mile, which, in turn makes the diff ratchet to compensate. Going with two newbys on one end or the other would be my suggestion, as if you are off-road in loose ground, it won't be "too" hard on the drivetrain when in 4x4, although I can't say I recommend it. The taller set will be slightly pushing/pulling the shorter set. Again, in loose ground, it's not that big a deal, as the old Fords often had 3. 55 out back, and 3. 54s up front... ... which still would bind up and you'd have to back up to get the t-case out of gear once on solid ground... . hope this helps, and good luck (especially if you're dealing with Discount (service) Tire)... ...

 

[HBarlow]

I think experts in the tire industry normally advise replacing both tires on the same axle not just one when one tire is worn.

 

[rjones]

Ive been running a new tire on the rear for the same reason above alone with a set that has 30k on them I have no ill effects and I'm not worried about that small of a difference ... . I now have over 4000 on that configuration now...

 

[TMax]

Well an update is in order and Discount Tire came through! I went to the original dealer that sold me the set of Cooper Zeons and he made it right. Thank you Gary at Dobson and Main in Mesa, AZ. He saw my predicament and cut me the same deal on another tire to match the set. That's all I wanted and props to him for looking out for the company. I'd highly recommend his shop for anyone and I should have gone there first instead of the idiots up here in Scottsdale by my work. Duh.