What is the max tread depth difference that you would put on the same axle.
I have just had to replace one of my Wintrac tyres that has just under 7 mm of tread with a new one that has just under 9mm.

As long as both are legal, I don't see it makes any difference?

If you read the handbook all 4 tyres should be replaced at the same time on the rrs but it says if this is not possible replace pairs on same axle  Wanted a Series 2 LR since childhood but previously owned MY16 Disco Sport HSE TD4 Auto, MY13 RR Sport Black Edition TDV6 Auto, MY10 RR Sport HSE TDV6 Auto, 2007 Freelander 1 Freestyle TD4 Soft Top, 2009 Freelander 2 GS TD4 Auto, 2007 Freelander 2 GS TD4, 2004 Disco 2 Metropolis Auto, 2002 Disco 2 GS, 2000 Freelander 1 SE TD4 SW

Still hoping for a S2 one day!

Judging by the differences we see on customers cars I don't think there are ant big worries.

A vehicle with matching tyres all round will perform better than with mixed makes/brands but we quite often see mixed pairs. Please call us 01737 241370 for the quickest response

www.ajstyres.co.uk

I have MTR's and tread depth on one rear is 11mm and the other rear is only 4mm.
No issues from the variance. Bodsys Brake Bible
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Of course....  Bodsys Brake Bible
Software Updates Contact me
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Clock On The Dash/ SNOTM /3Flash / BT Update /Service Reset/Error Codes read\ Gearbox Reset
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Of course -  16MY Estoril Blue SVR.............
17MY Autobiography Dynamic - Corris Grey - WOW.
14MY Autobiography Dynamic - SDV6 - Fuji White
12MY Autobiography - SDV6 - Santorini Black - Dual View - Rear Entertainment - Sunroof.
12MY Autobiography - SDV6 - Orkney Grey - awesome ;(
2005 Java Black - 4.2 V8 Supercharged First Edition- will never be forgotten ;(

^^^^ Peachy / Bodsy - Not sure what the 3 posts above have to do with the rest of us !

To answer the OP's question - scientifically.

You don't say whether you're on 18, 19 or 20 inch rims but it won't make much difference. The 2mm variation in tread depth would make a 0.0554% difference in the distance 1 revolution of the two wheels (that's based on a 20inch rim ). But, in the real world there's other stuff i.e. if the tyres pressures were exactly the same, there were no bumps etc in the road to deform the tyres - etc etc.

So I reckon you could comfortably say there will be no flaming difference

Thanks for the replies.
I have 20s on but I've heard some 'stories' where on a 4x4 that problems could occur but I'm thinking that this is on older cars.

2mm in tread difference as you say is not going to be noticed. If it did, every time you get a puncture etc then you will be changing 2 tyres at a time.

Cheers

In extremis, if one tyre was brand new and the other side of the axle had a tyre at the legal minimum depth you could find the stability control system gets a bit twitchy because of the difference in wheel speeds across the axle. But at 2mm difference in tread depth, as already mentioned by drdelrrs, it's going to be close enough to be lost in other variables. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Presumably the system expects the relative rotational values to be within certain values. If one tyre is excessively worn then it might fall outside of the relevant rotational value. That's my guess.

Or perhaps it's all down to LR setting up excuses to avoid warranty claims early in the life of the vehicle. "Oh, your diff has failed? That's because your tyres have 2mm difference in tread depth!" or some such rubbish. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

I was having a similar discussion with my colleague the other day, and mentioned that I had different tread depths on my tyres, but on different axles (front to rear).

He said that he wouldn't even advise that on a permanent 4x4, as it would see the 'viscous coupling having to work more than necessary'. Surely the fact that my fronts have 2mm more tread than the rears isn't going to have any detrimental implications? I would have thought that any mechanical components through the drivetrain would have an element of tolerance built in to eliminate such issues? I passed his comments off with a wry/dubious "hmmm". 2016 VW Golf GTD DSG
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The centre diff should always see zero relative motion between axles except on those rare occasions that one end is e.g. spinning both wheels i.e. in off road type conditions. It's designed to handle short term speed differences but not, I would guess, constant differences. By running with constant positive relative speeds between axles you will have shearing of the oil between the plates in the coupling and hence the temperature will rise. This probably isn't good for the oil. However, one would expect some tolerance in there somewhere.

In extremis, one might even cause wind up in the drive train but I doubt that's possible with just tyre wear differences. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Look at it from the other direction, you may have to replace tyres on one axle because they have worn quicker, fronts usually wear first, so the car in its original form is wearing tyres at different rates causing differences in rotational values across the axles, so unless you have 20's on the back and 19's on the front, it's not really going to be an issue..
if you were going up and down the motorway day after day after day the centre diff may warm up a bit, but even under light cornering the front axle is going further than the rear, drive through a puddle and then turn the steering, the rear tyre marks are inside the front ones, so the front goes further...  5.0 Ltr Superchrged RRS2, Chile Red, Sideways out of junctions!
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