am i right in understanding that the rolling radius/circumferance is the only figure that needs to be constant all round on a 4wd. i.e on the rear of my car i'll have 245/35/17's, but on the front i can have 215/40/17's? if that being the case, could i use 7.5j wheels on the front and 8j onthe rear, with the above tyres withought damaging my transfer box/differentials?

got rolling radius figures from here
http://www.falkentyres.co.uk/fk451.asp?cookiecheck=yes&

 

FK-451s are very good but FK-452 are the newer Falken tyres and improved dry grip.

 

well i have a pair of 451's lying in storage and need to get another two tyres hence the question and i have a 2wd set of comps, and was wondering if the front set of 7.5j can be used with the 8j's on my 4x4, and basically 215/40/17 452's are a lot cheaper than 245/35/17's. just me being stingy. the different tread patterns between the 451's and 452's should be a problem should they?

 

Tread pattern shouldn't make any differance but the width difference front to rear may, hopefully you'll get a reply from someone who knows something about 4x4s