Knocking Stroke Rubbing Noise

[maverp1]

I have quite a load knocking stroke rubbing noise coming from what seems to be under the gear lever it only happens after the car has been parked for a while and after about 100 to 200 meters disappears completely and the car drives great. Never noticed on test drive because as I say only happens after being parked up for a while .Any help much appreciated

Cheers Paul

[Guest Mister Dabsy]

Can you feel it through the pedals or steering wheel?

[maverp1]

Hi Jim deffo through the pedals after looking on here think it may be support bearing or coupling on the end of prop shaft .What do you think bud

[Guest DazH]

I had the same car and the EXACT same problem (1997 728i E38)

Reason: Exhaust bracket failure. Your vehicle has two back boxes. They are supported by a hanger which is welded to the box. This weld broke on the O/S box causing the box to slightly sag. This (although NOT obvious) was catching on transmission when cold due to the contraction of metal relative to it's temperature.

Diagnostics: With the car running (From cold), apply small amounts of downwards pressure to the back boxes. Listen for a change in noise.

Solution: Replace back box or simply weld the bracket back on dependent upon levels of corrosion. Assure ALL brackets (Including middle one) are tight as even the slightest drop in the exhaust will cause this knocking/rubbing noise on the E38

I'm pretty sure you will have the same issue that I had. Your symptoms are too similar for it to be anything else. Hope this helps

Daz

(Possible alternatives: Prop-shaft bearing - Transmission coupling (doughnut) - Transmission mounts - Torque converter - Differential mounts - Transmission failure - Engine mounts)

[maverp1]

Thanks to you all for all youre help DazH looks like you are correct my friend after getting you're message popped out with a tourch to check drivers side bracket on rear box has indeed snapped of will sort it some time this week and post to let you know results

Cheers Paul

[V8manual]

Thanks to you all for all youre help DazH looks like you are correct my friend after getting you're message popped out with a tourch to check drivers side bracket on rear box has indeed snapped of will sort it some time this week and post to let you know results

Cheers Paul

You could have checked 2 days ago when I first told you! ;)

[maverp1]

V8 sorry bud never saw you reply on here but thanks anyway just to let people know for future ref had the bracket welded back up to the back box and the problem has gone so as I said many thanks for all your help

Cheers Paul

[V8manual]

V8 sorry bud never saw you reply on here but thanks anyway just to let people know for future ref had the bracket welded back up to the back box and the problem has gone so as I said many thanks for all your help

Cheers Paul

Nah I was just taking the mick (755munich...)! :P

R.E. having them welded-BMW exhausts are made from a corrosion resistant material so while it's possible to weld them with standard steel MIG wire they may not last long as it's difficult to get good fusion between the 2. Mine just broke again after about 12 months. :mellow:

[maverp1]

Lol thought it may be you on 755Munich yes mate as you said the lad who welded it for me did mention this but I will be looking into changing the back boxes so as long as it hold out till then happy days

[Guest DazH]

Wonderful news. Glad it was nothing serious. You're welcome

Daz

[david1966hull]

Hi Paul. I'm 99.99% sure you've got a failing propshaft universal joint. It's seizing up whilst park then freeing as the propshaft turns. If you're mechanically capapable and have the tools, an houir of your' time and about 50 quid for the part should sort it.Hope this helps. Dave

[maverp1]

Thanks for your help David but as I said above it was the back box breaking away from the bracket that was causing the problem had it welded back in place and all is good now

[Guest DazH]

Hi Paul. I'm 99.99% sure you've got a failing propshaft universal joint. It's seizing up whilst park then freeing as the propshaft turns. If you're mechanically capapable and have the tools, an houir of your' time and about 50 quid for the part should sort it.Hope this helps. Dave

Wrong diagnoses although a good try. Problem solved already

Daz

[Guest Mister Dabsy]

No Daz, he was only 99.99 percent wrong :lol: :P