CQ 20v Rear Diff Prop clunk/bang.

[Pearl White Rob]

Sorry I know this is the second recent post on the topic:

I have had the car for about 3 months now doing various bits to it, before I got the car it received new diff mounts to the rear. Today I have just changed the 3 engine mounts and 2 gearbox mounts.

The car has done 160k and i did expect it to have a bit of 'clunk' or 'backlash' from the rear, however after seeing a vast improvement today from doing these mounts, I'm looking to perfect the smooth drive. Where shall I look next? Rear diff? Prop?

Many thanks in advance!

Rob

[steve briance]

Did it actually get new diff mounts? The rear mount is tricky to install so wonder whether it was missed? It is doable with a press/vice to get the new one in but getting the old rubber mount out of the aluminium housing involves FLAME and hacksaw

Prop shaft - possible but unlikely based on my recent experience. My middle mount had failed completely in that the rubber donut holding the bearing in the bracket had pretty much split all the way round, it was clearly not supporting anything but weirdly, i could not detect any clonking/banging from under the car. I changed it anyway but then ended up having to get the shaft re-balanced and in order to do that, both CV joints needed changing :-O Mildly annoying really seeing as it displayed no fault until i put it back on the first time!
On mine i needed to disconnect the exhaust from the downpipe to swing it out of the way enough to pull the heatshield away. You can't really assess play/looseness without getting a good grip on the shaft

[VagOrBust]

Talking about drive line clunks: Have you checked and/or replaced this b4st3rd?
https://store.034motorsport.com/audi...r-bearing.html
Mostly notable if you go off and on the throttle a few times in rapid succession.

[Nj]

Think that might be what I need. There's a heavy clunk when I let off the throttle quickly
**edit** or could be any number of other bushes

[Pearl White Rob]

Diff/Prop

Cheers guys I'l start with these, hopefully Il get a chance to get it up on the ramps at the weekend!

Its very noticeable under gear changes (although hugely improved after changing all the engine and gearbox mounts) and also on and off throttle (more noticeable at higher revs)

Rob

[Nj]

How were the engine and gearbox mounts to change Rob? Reasonable or awful?

[Pearl White Rob]

Engine mounts

All the mounts should have been a mornings work but I started at 9.30 and finished at 20.00 hahaha. Allow a whole day to do it just in case.

I drove the front of the car up some of those halfrauds ramps, and started with the bottom engine mounts. I supported the bottom of the sump with a trolly jack and a lump of wood, however, its almost pointless as the engine will just lower itself about 1CM onto the front crossmember! if you don't use a jack that is.

The O/S is easy to access and remove, you will have to do the top nut blind though unless you want to remove the exhaust manifold ( NO ). The N/S I found a pain but it did wriggle out, being careful not to damage the bottom rad hose. It was a squeeze though. On this one I managed to undo the top not from the top of the engine bay with a U/J on a Rachet and extensions. The Snub Mount came out a piece of piss next. Then I tried to get the new O/S engine mount it, but the engine/gearbox unit was still firmly in place so I abandoned and removed the N/S Gearbox mount (piece of piss, although they are not captive nuts/threads so you'll need to work out how to get a spanner in there). The O/S mount is protected by a little heat shield held on by three 8mm self tappers, as its close to the exhaust, remove this and you will see the mount. This one I found an absolute **** to get a spanner behind and hold on to it ( but I think It would have been much easier If I had the car up on a two post lift). Thats the removal part done.

I fitted the two bottom engine mounts first and had to jack up the engine to do this. The problem I had is Id start jacking and the whole car would come up, but eventually you keep going and it does come up, its just a heavy lump. Then fitted the gearbox mounts and the snub mount last. The worst was the snub mount as I had to slacken off the O/S mount to release some pressure to do it. I had to get a helper with a pry bar to then push the engine back and down a tad to then bolt it up. I think if you fit the snub first though, it will stop the engine doing up too much to allow the two bottom mounts to be fitted.

Anyway thats how I did it hahaha.

[Nj]

That's awesome info matey, thanks. I genuinely appreciate it. It's only by someone, such as you, telling about their experience that someone else has the chance to save a bit of pain (and chucking stuff around in frustration). I think I'll wait a few weeks until a guy I know here has his new 2 post lift installed, then call round and either borrow it or borrow it and him
Did you buy OEM parts from the dealer by the way? Engine mounts seem to be about 25 to 30 quid per side on ebay. I haven't checked the gearbox mounts yet.

[Pearl White Rob]

Parts

No Problem mate!

I bought, originally all 5 mounts from Euro, as they are on a clearance. However, the snub mount was completely different (partly my error), So I had to send my brother to GSF to get me the proper one ( euro couldn't get one for weeks! )

Think all the parts came to about 60/70 quid!

BTW GSF didn't list the snub mount online but we rang and they did have it! always worth a ring!

good luck with the swap! If I had more money to throw at the car I probably would have chucked on some uprated stuff but you cant have everything!

Rob

[Nj]

No Problem mate!

I bought, originally all 5 mounts from Euro, as they are on a clearance. However, the snub mount was completely different (partly my error), So I had to send my brother to GSF to get me the proper one ( euro couldn't get one for weeks! )

Think all the parts came to about 60/70 quid!

BTW GSF didn't list the snub mount online but we rang and they did have it! always worth a ring!

good luck with the swap! If I had more money to throw at the car I probably would have chucked on some uprated stuff but you cant have everything!

Rob

that's good to know about eurocarparts, thanks. and the snub mount, which there's a possibility of me ordering wrong too
Yeah a bunch of 034 parts would be nice but I too will need to live without them for now. Too many small jobs that all add up to a large amount

[steve briance]

hi Rob,

Your write up couldn't come at a more appropriate time for me!

Am currently looking to engine mounts as the next job on the car. I've just done gearbox and all 3 rear diff mounts and still there is a waggling gearstick, it is just not as bad as it was.

What part numbers did you order?

I've actually got another thread running at the moment about engine mountings and have been given some p/n but they are OE. What p/n and brand did ECP send you?

Going back to your banging clonk problem... while under the car, did you give the exhaust a good wiggle? Ive had odd noises from underneath before which i was convinced was a CV joint. It was actually the rear section resting on the subframe!

I only found this out once a pair of replacement CV joints turned up

[Pearl White Rob]

Mounts

Hi mate,
I think the two engine mounts were Q-Drive! seemed literally identical to the OE ones that pulled off it. The snub mount I cant remember Im afraid but the correct part came from GSF. I think this mount made the most difference I think on mine!

In regards to the clunk, the exhaust is solid, had a good waggle when I was under the car. The clunk is definitely the drivetrain taking up slack somewhere, a drive latency type problem, Loose diff sort of feel! but maybe my diff bushes were never done properly! If I could have that time I would like to get the exhaust off (it needs realigning anyway) and pull the rear subframe down to really see whats going on, refresh all the bushes paint it all up. BUT you know how it is! Iv'e got far too many projects hahaha

Rob

[steve briance]

yes <sigh> i know how it is.

I think you could get a good idea of any slack in the diff bushes by getting large flat blade srewdriver in as a lever. My rear diff mount was pretty sloppy and showed up pretty clearly without needing to get the subframe off.

Sadly I'm finding no amount of new rubber will sort drive train gear back lash