tyre issue

[LandCruiser1978]

my wifes car is a 90 swb 3.0TD auto
It has a set of mud tyres on it that are quite worn . maybe 3/4mm left on them ..
I put the spare onto the front yesterday (the spare is unused so has 12mm+)

My question is
Will having 1 tyre with a greater rolling radius cause any problems with the Transmission ? i.e windup

or has Mr T made the landcruiser from tough stuff?

 

[Jon Wildsmith]

the side gears in the front diff will be turning a lot more than normal with such a big difference and as they don't run on roller bearings, just hardened metal on metal, that could be a bit of a problem eventually. In the short term it shouldn't cause a problem but I wouldn't leave it like that for too many miles but I have no idea what too many miles might be I'm afraid.

 

[LandCruiser1978]

is it better on the back?

The old tyre is goosed so until she gets new boots it might have to live like this for a while

 

[BobMurphy]

is it better on the back?

It would be better on the back as it won't affect your steering to the same extent if you hit water / snow / ice.

See my reply to your question on 'the other site'

Bob.

 

[LandCruiser1978]

cheers bob your a star



copied from TLOCUK

Answer = No

As you have three differentials the drive is evenly split across all four wheels all the time.

If you were to lock the diff in the axle that the 'slightly different' wheels were on there would be some wind-up, but probably much less than you would get when cornering. I guess you don't have a front diff locker, though

As it is, the front diff will just act as though you are on a permanent gentle curve, with one wheel turning slightly slower than the other.

It might affect your braking & steering under extreme conditions (i.e. surface water) though.