XSeries-forum

Hi, I have recently purchased a 2003 x5 4.6 sport, although I am definitely not new too the BMW brand, I am new too the x world..
The car has recent two new tryes on front, cheap make but seem OK..on the rear are 2011 bridgestones..they have a little life left..but not huge, I have been told by my mechanic.. That diff tyre depths in a big way can cause the diff too wind up..is there a limit if I stick part warns on.
I am truck driver and work away most of the time..so it really don't warrant £400 tyres on it..heard there could be a margin of 2-3mm...can anyone tell me of its and true and what the deal is..nice truck by the way...huge amounts of power.. Lol

Is it the pre face lift or post??

Pre facelift then you shouldnt have the XDrive module on the transfercase in which case i personally (my view) dont think you need to over worry on that score!!

Having had my transfer box apart before i cannot see how this box would ever get affected by "Diff Wind".
there is a planetary gear set in there and compensates for the interactions between front and rear.
Lets face it the traction control on these is controlled by differential braking and therefore the diffs and transfer box should be designed to cope.
Again my view is that it will.

You would only experience issues if you have limited slip diffs etc fitted.






However if it is a facelift version with XDrive, then you are on your own!!!
(See below)

All 4.6 were pre-facelift as far as I am aware 2002 to 2003. When I first got the 4.6 it was running odd tyres front to rear and on the rear different makes across the axle, while they were legal they were a real hotch potch as far as wear was concerned. It ran for a month with no issues before I could change them.
So providing they are the correct sizes Front 275x40xR20 Rear 315x35xR20 I would say your OK for a while

Cheers guys..it is the prefacelift model..estoril blue..nice bit of kit, but was warned about the tyres...looking on the net, there is no clear indication of whether the info was right or not....