Tyre Size

[BIGBALLS]

Not been on the forum for a long time but still have my 60000 genuine milage
EXPLORER. I have a pair of 265/70 x16 tyres which i would like fitted i also
have a pair of 255/70 x 16 like new already fitted on the rear.
My question can have these tyres fitted on the car NOT on the same axle the
4x4 switch will always be in the Auto position. I have driven in 4x4 high or low
Cheers BB

 

[jayjay101]

ive got 285/70r/16 and thay work fine so would think thay would b ok

 

[janolsson]

I would suggest NO as the 4x4 would sense the wheels on one axle turning at different speed to the other axle as the circumference is different.
You could find a part worn place that will swap one of the pairs so you have 4 matching sizes esp if you pay them to fit!

 

[BIGBALLS]

The dia. difference is only 14mm and i don't intend to use the 4 wheel drive

 

[janolsson]

That difference equates to nearly 4% or 1 revolution for every 25 revolutions. Not sure what the tolerance is for the sensors. In auto mode the sensors look for the wheels turning at different speeds to determine whether or not to engage full 4wd.
You could be totally fine or you could toast the transfer case. Maybe if you post in the transmission/diff section one of those experts could give you a definative answer as i'm guessing.

 

[blueka]

you will have issues if you run 2 diff sizes on the 2 diff axles, keep the same size at each corner.


Si

 

[kevin p]

Stick this in the equation. What if you have nearly bald tyres on one axle and you put new tyres on the other? Commonly 10mm+ deep tread on a 4x4 tyre = 20mm diameter.

 

[chrisquelch]

what if the front are under inflated and the rears are over inflated ? i would run all 4 the same size on a 4x4 with auto engage just in case . cheers chris

 

[kevin p]

I would as well chris. Just trying to point out there must be a little bit of lee way. As long as the tyres have the same rolling radius it shouldn't matter what width they are.
Kev.

 

[chrisquelch]

yes as you say rolling radius if what matters and as long as the extra width doesn't foul the body it should be o.k.
cheers chris