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View Full Version : Why am I changing thrust arm bushes more than my underpants?



632 Regal
05-18-2008, 05:14 PM
Agreed the M5 bushing fix. Yes a bad shock can couse the problem to escalate. Why spend so much for shitty shocks? I blew 3 in a row and then threw them away. Boge/Sachs are fantastic in comparison IMO

e34.535i.sport
05-18-2008, 05:54 PM
I've had to change my passenger side thrust arm bushing twice in the year or so I've had the car and it now needs doing again. WTF?

The first time I done both sides wasn't long after getting the car... I used the same parts (cheapo ones) and haven't had any problems with the drivers side at all since. The passenger side however is a problem.

For a LONG time it's been wobbling when going over bumps or small dips in the road. It's a violent up and down motion as far as I can tell. Bounced the corner of the car and it took a few up and downs to settle. The drivers side settles much quicker. This made me think about the shock being past its best. Also tried to move the wheel with my hands at 3o'clock and 9o'clock. It had a little play. I then tried it with hands at 12o'clock and 6o'clock. No movement.

When looking around I noticed thrust arm bush gone. Changed it and it went a bit better for a while. Now it's worse than ever.

I have a suspicion... I *think* the wobble could be to do with the passenger side shock given up. If this is the case could it have caused the thrust arm bush to deteriorate quickly?

I'm in a bit of a tricky situation at the moment as I have two front Bilstein B8's on order for Tuesday (should've been last week but the guys at the parts place are muppets) and they're going to set me back £180ish... I ordered these thinking the passenger side shock is causing the wobble. I'm also considering buying the powerflex bushings for the thrust arms and getting them pressed in to solve the problem... However these are expensive too and I'm strapped for cash - it's one or the other for a week or two... What's my best bet?

Footnote - I torqued all of the bolts for the thrust arm etc as per the haynes and the pivot bolt under load... I done exactly the same on both sides of the car too which is what makes me think something else is wrong with the passenger side as the drivers side has been fine.

winfred
05-18-2008, 06:47 PM
theres a few causes of the shimmey, shocks, bushings, rotors, bad rim/out of balance tires and ball joints, sometimes theres just one doing it but several can combine

the stock blue e34 bushings suck to start with, the green 740/750 e32 bushings are slightly better but the cure for bad bushings are the black e34 m5 thrust arm bushings, they drop right in and work but if theres enough wrong with the rest of the suspension a shimmey is still possible

bubba966
05-18-2008, 06:59 PM
A bad shock will kill your thrust arm bushing rather quickly.

They can also be killed quickly if they aren't installed properly. The bushing has to be oriented in the arm properly. And the bolts have to be torqued down with the car sitting as it normally would so that the suspension is compressed a bit when you torque it down. I can't get underneath my car when it's not on ramps, and I don't have a 4 post lift. So when I do mine I'll put ramps under all four corners so that the suspension is properly compressed and I can then install the new thrust arms & bushings properly.

And don't use the cheap Meyle or other blah bushings as they'll just crap out within a year or so. Get the Lemforder M5 or 750 bushings and do it right.

SnakeyesTx
05-18-2008, 07:17 PM
Had the same problem as you... went with 95 840i Bushings instead of the original ones, direct replacement and solid, not the liquid filled crap. After about 2 weeks still had a shake, found out the struts were bad too. Two new strut cartridges and the car rode sweet for 2 years no problem before she got totalled =/

Jehu
05-18-2008, 07:19 PM
M5 bushings lasted longest for me too, only just now about a year later beginning to have some steering wheel bounce at certain times. Enough to consider plopping in a new pair. I had them installed when i had the new Bilsteing Sports installed and soon thereafter did the tie rods so i got to enjoy a perfect front end for a while :) Pot holes and other road issues though have savaged the wheels and the bushings i have to assume took one too many impacts at highway speed .

Ferret
05-19-2008, 04:18 AM
Shot shocks finished everything off on the front end of my 525TDS, totally wore out the balljoints in 4 months, and I didnt even realise I had a busted shock till it was too late! The Front ARB on the TDS is super strong!

Ferret
05-19-2008, 04:19 AM
Why did the forum randomly attach my reply to 632 Regals post?

e34.535i.sport
05-19-2008, 11:07 AM
Agreed the M5 bushing fix. Yes a bad shock can couse the problem to escalate. Why spend so much for shitty shocks? I blew 3 in a row and then threw them away. Boge/Sachs are fantastic in comparison IMO

Hey Regal... I though Bilteins were the dogs bollocks - You reckon Sachs shocks are the one then... I'll look into that.

I know what everyone says about ebay but what about these - they seem like what I need and can change the rears too for even less than just the front Bilstein B8's:

http://cgi.ebay.co.uk/4x-Sport-shock-Absorber-BMW-E34_W0QQitemZ280177301570QQihZ018QQcategoryZ40192Q QrdZ1QQssPageNameZWD1VQQcmdZViewItemQQ_trksidZp163 8Q2em118Q2el1247

They seem to get good feedback and its a good price for all four. I keep worrying about the normal sports shocks fitting mine as it has the M-tec suspension, will there be any issues?

e34.535i.sport
05-19-2008, 11:10 AM
Thanks guys - good to confirm I need shocks first then do the bushes. I'll see how the M5 and Powerflex bushes compare pricewise and make a decision.

What's a reasonable price for a garage to press in the bushes for me?