Tread depth & differential question

[cperez]

How much tread depth difference between tires is too much for the 2013 LR4 differential?

Per my latest post in the Continental TerrainContact A/T thread, I lost one to a sidewall cut this weekend. The others have 11K miles on them, or ~80% tread remaining. No one I've found in the DC area does any shaving of treads for this type of situation.

I have not done any measurements yet between the existing tread depth and the depth of a brand new tire. I'm just going off mileage as a rough starting point as I consider this. One of my indy mechanics thinks our diffs are super sensitive to differences, others not as much (within reason of course).

Thoughts?

 

[mbw]

I would guess you will be fine. Hard to really know what the threshold is.

 

[ryanjl]

Is the 80% based off actual measurements, or just an estimate on expected tread life?

 

[cperez]

Is the 80% based off actual measurements, or just an estimate on expected tread life?

As mentioned, it's not off measurements. This is a 60K tire so it's just a very rough estimate. Even if I had current vs new tread specs I would still need to know what our diffs will tolerate in terms of % differences. I wonder if that value is even available...

 

[mbw]

As mentioned, it's not off measurements. This is a 60K tire so it's just a very rough estimate. Even if I had current vs new tread specs I would still need to know what our diffs will tolerate in terms of % differences. I wonder if that value is even available...

I looked around in the factory service manual and didn't see anything. Saw something on tirerack....

Audi As published in their vehicle owner's manual, "rolling radius of all 4 tires must remain the same" or within 4/32-inch of each other in remaining tread depth.
Porsche Cayenne within 30% of the other tire on the same axle's remaining treadwear.
Nissan GT-R when replacing less than four (4) tires, each tire continuing in service must have at least 6/32 inch (5 mm) of remaining tread depth.
Subaru Within 1/4-inch of tire circumference or about 2/32-inch of each other in remaining tread depth.

 

[mbw]

I looked around in the factory service manual and didn't see anything. Saw something on tirerack....

Audi As published in their vehicle owner's manual, "rolling radius of all 4 tires must remain the same" or within 4/32-inch of each other in remaining tread depth.
Porsche Cayenne within 30% of the other tire on the same axle's remaining treadwear.
Nissan GT-R when replacing less than four (4) tires, each tire continuing in service must have at least 6/32 inch (5 mm) of remaining tread depth.
Subaru Within 1/4-inch of tire circumference or about 2/32-inch of each other in remaining tread depth.

GTR.. 1/16" hot damn that's picky.

 

[ryanjl]

Well, if you rotate with a full-sized spare, you're incorporating a brand new tire in the mix at around 7,500 miles, so 11,000 isn't much more than that.

 

[cperez]

I looked around in the factory service manual and didn't see anything. Saw something on tirerack....

This is all very helpful, thank you. Even though it's not Land Rover-specific it gives me some context. I also asked a couple of LR master techs who are in my local owner group and both of them quickly answered that I would be fine installing a new tire into the mix. Both of them were with me during this wheeling event and are familiar with my vehicle.

 

[cperez]

Well, if you rotate with a full-sized spare, you're incorporating a brand new tire in the mix at around 7,500 miles, so 11,000 isn't much more than that.

That was my general back-of-napkin reasoning as well, Ryan. Good point. I'm replacing the single tire this time. If I funk up my tranny, you guys will be the first to know...you'll certainly know before I confess to my wife.

 

[cperez]

The consensus I'm hearing is that I should not be concerned about this and adding a single new tire is fine in this scenario. I spoke with a knowledgeable tech at Discount Tires Direct where I bought these originally. He also runs a full-time 4WD vehicle and said that he would not be concerned about doing this on his own vehicle unless he had 25-30K miles of wear and tried to introduce a new tire into that mix.

I'm doin' it. Thanks for the input.