Gears Clunking. What Could This Be?

[paulh617]

Only tonight i notices my bmws gears started clunking. Every single gear. During the change it does not feel smooth. There is a clunk sound coming from the mid to rear end as if i can physically hear it engaging. Any ideas what the problem could be guys?

[Guest DazH]

First thing I would do is change the Tran fluid and see what happens :)

[stebaz47]

drain fluid renew if that does not work new gear box

[paulh617]

Cheers, i have done a bit of reasearch on this and am getting a lot of different answers. main ones being, a common problem is the donught that connects the prop shaft to the gearbox, had it on the ramp today and this looks new, some people are saying it a normal clunk, and also heard it could be the rear diff bushings/mounts. I may start off getting trans fluid and diff fluid changed, if this dont work maybe look at getting the diff bushing replaced?

[barney]

put her up on 2 axel stands (make sure shes sturdy) start her and get a mate to go through the gears and have a watch of the diff and see where the nose is coming from i would say its prob the diff. i have broke 2 in 12 months!

[Guest Mister Dabsy]

... While its on stands, neutral, grab the prop and twist it in each direction and notice any excessive noise or movement at diff before a road-wheel turns.

[paulh617]

Cheers guy i will have a good inspection of the diff see if i can locate the problem. Couple of questions. If i was to have the diff or bushings changed what are we talking in labour costs? A big job removing the drive and prop shafts not something i wud wana do myself. also can anyone recomend what oils to use for the transmission and difderential.

[barney]

i use 75w-90 redline gear oil i get it of ebay about £18. as for bush replacement i aint to sure you can pick whole new diffs up cheep enoth tho as for cahangeing them over its fairly simple you just need a big female torx bits to disconect the diff from the drive shafts the prop shaft is just 4 bolts......... axel stands and a hayns you will save your self a packit!