Front suspension arms

[Nick Jones]

Have both an A8 (D2) and A4(B6) with MoTs looming and clonking front suspensions. It's not the ARB droplinks.....

This means messing with the stupidly over-complex, maintenance hostile front-end of both cars.

While it's vaguely tempting to apply the scatter gun approach and replace the lot, to do so (with decent quality parts at least) is uneconomic. Makes more financial sense to call the knacker and buy a Honda instead.

So I need to try and find the sources of the clonks, which previous experience has shown to be tricky without the MoT man's shaker.

Any pointers? - are there some which typically fail first or are known "clonkers"?

Thanks

Nick

[MikkiJayne]

"maintenance hostile"

The prime candidate is the upper rear arm as the bush in that is woefully inadequate. Next is the tie rod end balljoints, and then the lower rear arm inner bush. The front arms rarely seem to have major failures.

[Ronin]

I've had all my front control arms on the d2 replaced even though only half of it was bad and I would do it again, its pointless to replace 1 10-15 year old arm only to have the other fail in 3 months.. parts cannon approach is best in case of the front suspension

parts were 430 (inc front roll bar bushes) for Meyle HD and labour started off at 250 but ended up at 360 inc. front wheel alignment.

[Nick Jones]

Thanks for the insights MJ. Definitely maintenance-hostile….. I have established the the OS pinch bolt on the A4 isn’t coming out without a major battle. It started to move, then stopped. Managed to return it to its working position without snapping it.

Out of curiosity and in an attempt to understand the mot advisory from last year, I disconnected the TRE so I could swing the assembly through the steering range. Wow. What was it’s designer smoking? I find the way and the extent to which it relies on the compliance of the inner bushes to function most surprising.

As to swapping the lot, while I do follow the logic, I certainly don’t like the A4 nearly enough to do more than the absolute minimum to keep it running and legal. The A8, tougher decision.

One bright spot was having failed to find anything obviously knackered, I put it all back together and drove it. Clonk gone. I have no idea why……

I’m going to put it in for MoT and have the man tell me what he thinks it needs. Maybe this years man will be less picky…..

First I have to sort the check engine light (ECU thinks the the EGR valve is malfunctioning. It’s right, it is, but I was hoping it couldn’t tell when I disabled it!)

Nick

[MikkiJayne]

Originally Posted by Nick Jones

It started to move, then stopped. Managed to return it to its working position without snapping it.

If it turns thats 95% of the battle. Usually if it comes out a bit then gets stuck its because it's been over-torqued and is bent at the nut end. They can usually be persuaded out in that case - an impact driver helps to get the bolt turning while it's levered out. The alternative is to cut the ends off and drive it out with a punch, but only if it does move at all, otherwise you'll be drilling it.

If they don't turn then they can sometimes be jacked out from the nut end by snapping the head off and then putting a stack of washers under the nut and tightening until the stump starts moving. Always put something in the gap of the clamp parts then though, otherwise tightening the nut just snaps the top off the strut!

[Nick Jones]

Excellent info there.Thanks!

Nick