need advice regarding issue with a recent purchase

[Razzy Man]

Hello there.
I recently recently bought a present for missus' birthday in the form of a 2004 bmw x3 2.5i manual(the manual bit is important). We bought the car from a garage 20 miles away from us and the trader seemed genuine and the car seemed genuine. He was asking 4 grand for it, me and my son chipped in for a bit and the rest 2 grand I paid with a credit card. My reasoning being (just in case something is dodgy). To top things off the trader offered us 3 months warranty.

Now all was well until we got home and he took it for a longer drive where it started to cough as if something was cutting the power but it didn't feel like a misfire. I called up the dealer and they said to bring it back down to have a look at it. They did diagnostics tests on the engine and it was fine and they kept scratching their heads and saying (keep driving it until a light comes on or it stops then bring it in). I didn't we took it to a bmw specialist near us and the technician there said its the transfer box as its a common x3 fault and it doesn't show up on any codes apart from "oil wear sensor". That or someone has put the wrong size tyres on the back causing the xdrive system to go ballistic and doing the above.

I took the car straight back to the garage where we bought it from and said to them as we had everything the bmw specialist said written down with a quote to fix it and the bloke who owns the garage just went "ehh...sensor??? but its a manual it doesn't have sensors. its impossible" and after much arguing he agreed to drop it off at "his gearbox place" and has been sitting there for 2 weeks now cos he "was too busy to go down there" and see what needed to be sorted.

Every time we go down there theyre like little lambs and say "yes we'll change the tyres or transfer box and the warranty will cover it" and then when we leave and call up they're really rude and say that they have better things to do". I said to them that I'm coming to pick up the car tomorrow regardless if they have done anything to it or not and we will have to sort the situation out because its been 3 weeks now and its just mostly been sitting in their garage.

I'm now hoping I can give the damn thing back I don't want o be stuck with paying out for a transfer case. its bad enough I had to fork out 1500 quid for a rebuild on my x5 gearbox because the torque converter lunched itself and took the gearbox with it on holiday in france. Don't want to go through that pain in the backside again.

thanks in advance

[BertBert]

Surely you have ruled out wrong size tyres?

[Razzy Man]

We just have because the alloys on the car are 17 inch and the tyres are 235/55/17 dunlops all round. and the problem apparently only applies to the 18 inch staggered alloys as the backs are 255/45 and the fronts are 235/50. Which means the transfer box is dying.

Edit: reading up a bit on the tyres now ive discovered that they need to be star rated (manufacturer OE) tyres so it wont have any issues. it currently has dunlops (cheapy ones) and bridgestone turanzas are the recommended ones

Edited by Razzy Man on Friday 16th October 12:00

[ging84]

the star just means they are bmw approved, you don't actually need them so long as they are the right size
if a normal car was so sensitive to tyres it could not take off the shelf tyres and needed them to be specifically tested and approved by the manufacturer, the car has a design fault.