If he can get the 'exact' brand and size he already has and if he has
open diffs and part time 4x4 he can get away with it.

He has to put the two new ones on the same axle if he has a limited
slip. But that brings up reversing the spin on one of the whole tires
which can cause them to explode from belt separation. (ya ya I know
'they' say new tires aren't 'supposed' to explode like that anymore, but
once bitten a dozen or more times with used tires, I just don't believe
whoever 'they' are, plus both of my Jeep owners manuals say not to cross
rotate.)

The size difference from front to rear can mean he will have 'fun'
trying to get out of 4x4 on occasion, the t-case will wind up so goosing
it in reverse might be needed to make the shifter move. If there is too
much difference in wear, then even 4 high would be useless because you
can't shift out of 4x4 on the fly if it winds up.

Putting a different brand of tire on is 'not' a good idea. Brands flex
totally different so the vehicle could either dive into a turn or skew
the arse end so it swings out unexpectedly on a turn.

My $0.02,

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Serg wrote:
>
> hey guys-so my cousin runs over a wheel/tire that some jackass drops on the
> freeway. going about 80 mph, he hits it and flattens both left side tires.
> got towed to Pep boys (closest place) and gets told he need to change all 4
> tires because he has a 4wd car and only changing 2 could damage his
> drivetrain. what do u think about this?
>
> i say BS. shouldn't the differentials handle the slightly different tire
> sizes ok (new vs old) and in the snow, the tire slipping on the snow would
> take care of that too right? he's in colorado (boulder) so snow is a
> concern.
>
> they are trying to sell him a pep boy-brand tire or something else that
> costs a whole lot more ($95 pepboy tire vs $150 other brand (can't remember
> which). no, they don't carry bfg's
>
> thanks!