Thread: TYRE REPLACEMENT QUESTION - NO NOT WHICH ATR TO FIT

Definitely not a good idea to mix treads and circumferences!!

Perhaps someone with appropriate teknikal ability can give an indication of the amount of difference in circumference needed to cause a problem as no two tyres would be exactly the same especially after being roaded for a while.

My biggest concern would be the handling changes associated with different tyre construction rather than rolling circumferance or adhesion, which might still present problems. You may have to try where to fit the new tyres as whilst the new ATRs would suggest to have less grip on sealed surfaces so fit them to the front, they have quite stiff sidewalls so oversteer might be a problem and thus they might need to be on the rear. Anyway, if you didn't like the steering with 2 ATRs, get 2 more and ditch the almost worn-out HTs. Maybe do that from the outset!

As a bit of a datum.... I once had 19" MTRs on the rear and the OEM 19" HTs on the front. Stability control went off like Xmas and on rough bitumen it drove as badly as an old Nissan Patrol. Obviously the computer was very confused and I'll never do that again. Still this is more extreme than going from HTs to ATs. Oddly enough the MTRs were the same rolling size at 265 x 60R18 Cooper HT+ and mixing those two tyres worked okay (I did this as a controlled test only and wouldn't recommend doing it).

G'day George,

I have four tyres with a 4mm difference in tread depth (2 at 8mm and 2 at 4mm) and a fifth that's different again. Several LR and non genuine LR workshops have told me "Just don't do it" 4mm is too much difference in depth.

As a result I am running around on my 17" off road set until I have the ready's for a new set of 18" black-top tyres.

HTH,

Ryall

Hi There,
When I was buying my D3 the person I was buying the vehicle off had put the spare on due to him having a puncture, the tyres fitted were 255 55 18's the spare was a 255 60 18, this had the effect of activating the traction control and making the gear changes on the vehicle different. When I replaced the punctured tyre with a new 255 55 18 and kept the other three as the old 255 55 18's the vehicle ran a treat, no noticeable difference. There must be some built in safety allowance to allow for minor discrepancies in tread wear. Definitely would try and keep the same sizes on the vehicle I wouldn't have different brands on the same axle, I would consider the same size same brand on one axle and a different brand same size on another axle. That's me, my opinion. Hope this helps.

Even having one tyre a bit flat will activate the traction control, especially on corners. It obviously makes a difference.

Don't as even small diam tyre changes upset limited slip diff's with traction control.