Differential damage due to tire tread?

Last week I removed my winter tires to install my summer tires. Unfortunately and to my surprise one of the tires had a patch in it from I assume a small nail. Because it was just a patch and not patch AND plug the tire shop was not able to install it due to liability. They left me with two options neither of which ideal. Either I buy a new all season tire and have it installed or I put one of my winter tires back on. For safety reasons I bought a new all season but only one. So now I have three continental crosscontact tires at about 5/32nds and a Rocky mountain ht2 at 11/32nds. I'm aware it's very important to install tires in pairs but they only had one in stock. Because the crosscontacts are getting to end of life i was planning on getting some light AT tires in a few months. However, I'm also not sure how long I'll have the tahoe so may not buy new tires. My question is am I at risk of imminent diff damage since one tire is at 5/32 and another is at 11/32nds? I definitely don't drive aggressively/ spin the tires. Do I rush to find a new tire for the rear that is the same as what i have on, or am i ok for a few months until i get AT tires?

2015 LT 4wd

My opinion is that you'll be fine. That's what diffs are for.

If you're really worried about it, put the mismatch on the front (I'm assuming you run in 2wd most of the time).

intergalactron said:

My opinion is that you'll be fine. That's what diffs are for.

If you're really worried about it, put the mismatch on the front (I'm assuming you run in 2wd most of the time).

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yes have it in 2wd 85-90% of the time. i do have noise coming from transfer case but that is another issue that arose before the whole tire mess

bigred2015 said:

... now I have 3 continental crosscontact tires at about 5/32", and one Rocky mountain ht2 at 11/32".

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Overinflate the 3 continentals (40psi), underinflate the Rocky Mountain (32psi).
If you put the Rocky Mountain in front, stay in 2WD for as long as reasonably possible.
If you put the Rocky Mountain in back, put it on the right rear.

bigred2015 said:

... am I at risk of imminent diff damage since one tire is at 5/32" and 3 others are at 11/32"?

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Damage, no. WEAR, probably.

Marky Dissod said:

Overinflate the 3 continentals (40psi), underinflate the Rocky Mountain (32psi).
If you put the Rocky Mountain in front, stay in 2WD for as long as reasonably possible.
If you put the Rocky Mountain in back, put it on the right rear.

Damage, no. WEAR, probably.

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what is the reason for over and underinflation? Sorry i should have mentioned the rocky mountain is left rear. Wear is not a concern for me, diff/ other trans damage IS.

Overinflating makes (shorter) tires slightly taller. Underinflating makes (taller) tires slightly shorter.

Were I you I'd try to find a way to wear down the taller tire.

Hey, what about your spare?

the tires are the same specs (width, aspect ratio, and diameter) just different tread depths

spare tire is a no go as its not the same specs and can go max 50mph

You have good advice already, run the new tire on the front and don't think about it any more. The front differential is an open differential allowing the two front tires to roll at different speeds no problem.

Your rear differential may be a locking differential, most are. You want the rear tires to be the same size as much as possible with. locking rear axle. Uneven tire size can cause differential wear or damage.

If your rear differential happens to be an open diff like your front you can run the large tire front or back but I would still advise the front.

West 1 said:

You have good advice already, run the new tire on the front and don't think about it any more. The front differential is an open differential allowing the two front tires to roll at different speeds no problem.

Your rear differential may be a locking differential, most are. You want the rear tires to be the same size as much as possible with. locking rear axle. Uneven tire size can cause differential wear or damage.

If your rear differential happens to be an open diff like your front you can run the large tire front or back but I would still advise the front.

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new tire is currently on rear, I could move it up to the front and rotate when i find time but not sure when that would be.

If you're sure the diameter is the same, I call it a non-issue.

joe

homesick said:

If you're sure the diameter is the same, I call it a non-issue.

joe

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yes same tire size 275/55/r20 only difference is tread depth

bigred2015 said:

yes same tire size 275/55/r20 only difference is tread depth

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I've never had an issue like this, but have seen and heard, many times over the years, that the same size designation from different tire brands can have minor differences in actual measurements.

joe

The 2 tires have the same overall diameter when new at 31.9". As such, there is only a 3/16" difference in overall diameter at the current wear status.

I like the different tire pressure suggestion to zero out the slight difference in current overall tire diameter, but if mounted on the front axle, it probably is not needed.

Not an issue. Only an issue if you had the AWD transfer case like in the Denalis where you can’t select anything and it’s just always in AWD. Even then you may be within the limits of tread wear differentials.

This would probably be a problem in Jeeps with the quadratrac transfer case. Those had very tight store wear tolerances and would burn up the clutch’s in the transfer case if tires weren’t nearly exactly the same tread wear.

It's a non-issue.
Also, "Because it was just a patch and not patch AND plug the tire shop was not able to install it due to liability" is a lie they told you to sell you a tire. Just FYI

Agreed, they used it to sell you a tire but ideally they wanted you to get two.

Couple of things:
- Tire size means nothing... overall actual tire size for the same "labeled tire size" are different from one manufacture to the next. This is why they do not recommend mismatching tire brands but also this is due to tire compounds, handling characteristics, tread patterns and wear.

- Your truck has differentials which are either posi traction, or open with electronic locks to engage in 4wd. The point of a Posi is to lock the wheels but also to allow the tires to rotated at different speeds (when you are going around a turn vs straight). When you turn the inner tire moves a shorter distance than the outside tire. The posi will allow the wheels to move at different speeds so you don't get noise, uneven tire wear, added stress on the system. This is not to mean that you want this "slipping" ALL THE TIME which is what you are doing essentially. This will cause premature wear of the slip mechanism which can be friction plates, cones or some other mechanism. While I have put a single new tire on worn cars that tire was the same brand and size so its just the tread wear your making up and not the differences in manufacture size and compound. If this was me I would have taken it to a different shop, plugged the tire myself and had them install it or where you are now... get another matching tire for the opposite side sooner than later. Your not going to see huge changes between manufactures but there are so many things that affect the installed DIA. Vehicle corner weight, the air pressure, tire construction, compounds, layers of steel or kevlar belts and anything that affects the sidewall stiffness. That gets compounded by the tire compounds, and tread designs which affect how the tire behaves at certain temps and road conditions.

- Your truck is not as sensitive as some of the AWD systems (Subaru's are real bad) but I would still fix it with replacing with a matched tire on the other side.

- I'm not sure how the size of tire will affect your wheel speed sensors, or if the systems are even sensitive enough to measure that difference. I would suspect not as they have to account for wear but also would have tripped the ABS or traction control systems by now.

No, you're not at risk of damaging anything including the differential & no gimmicks are required

I would get a new tire guy, nothing wrong with a patch only for a nail hole; you bought a tire for no good reason

I've had many leaks repaired with plugs, no patches, over the years with no trouble.

joe

If the patch was the stumbling point why did they not just replace it with whatever method to their satisfaction?
My shop does repairs and routine maintenance for free. I try to throw money at the owner but never get away with it.
It would be time for a different shop for me in your situation.

Goldwing2000 said:

It's a non-issue.
Also, "Because it was just a patch and not patch AND plug the tire shop was not able to install it due to liability" is a lie they told you to sell you a tire. Just FYI

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i argued with them asking them to just put the tire back on and they wouldn't budge. very annoying but it turns out its quite difficult to drive with only 3 tires. good to hear it's a non issue. If i keep the tahoe for more than a few months which i hope to do, ill buy a full new set anyways