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Discussion Starter #1
It seams no sooner do you fix one problem and another comes along!

The wife borrowed the car a few weeks back and complained bitterly about the steering (normal car a Discovery!). Over the next few days I had to agree and the problem seamed to be getting worse...in fact the handling was falling appart.

The car was shaking and shuddering taking constant radius curves (very unsettling on a slip road), it was tramlining, unstable in side winds, axle tramping was another symptom, transmission shunting, the steering was generally awful.

To cut a long story short I've replaced the axle carrier bushes and, though not strictly necessary, the pitman arms which has sorted all of the above......basically transformed the car's handling. Its amazing just how bad they bacame over such a short period of time and just how much can be done with £100.

This really is an easy thing to do and worth it before replacing shocks and the like. Especially if you apply my 'bodgers' approach which avoids any of the special tools it probably mentions in the manual..........
 

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ECM4,
Glad to hear your repair was cost effective. Your symptoms are similar to mine - although more severe, and I too suspect bushes somewhere as my shockers are relatively new. Just to clarify (and sorry to sound stupid) - the axle carrier and pitman arm bushes are where exactly? Did they appear obviously worn or did you make an educated guess? Also - if you have part numbers for the bushes you used, I would also be very grateful.

Many thanks

Kurt
 

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Discussion Starter #3 (Edited)
Actually Kurt it was a bit of both...it occured to me that the car was behaving a bit like it had a beam axle. I got so sick of it I run it round to the loacal specialist and described the symptoms. He thought it was the shocks however we put it up on the ramp and levered around with a pry bar. Sure enough it was the bushes.

The E30's and E34's (maybe others too) have a large beam which runs across the rear of the car just forward of the rear arch. The rear trailing arms swing from this beam which also carries the rear diff, anti roll bar and some other stuff. All the acceleration, braking and cornering loads are carried by this beam and reacted into the body via two large bushes either side.

Look under and behind the sill in front of the rear wheel and you will see the threaded end of the large bolt which passes down through the floor and through the carrier bush.

The pitman arms are slightly different. You can see them (I think) by looking at the trailing arm through the wheel arch in front of the rear wheel. They are basically a short link with a sealed rose joint each end, one end connected to the carrier, the other to the trailing arm. I presume they prevent lateral movement of the arm. They take minutes to change.

The bushes and arm's are standard for all E34 as far as I know. My guys had a dozen or so of each in stock. I think the following links should explain things better.

Axle carrier bushes (item 2)
Pitman arms (item 6)
 

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It's the rear of my car that I suspect too, so this info is really useful - thanks very much. The RealOEM diagrams are a help too.

I take it the special tools you avoided using were the ones need to remove / install the axle carrier bushes?
 

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Discussion Starter #5
Kurt,

I suspect the BMW 'way' involves an extractor of some type. I think the local specialist has one but he never uses it! One of his mechanics explained how to remove the bushes by heating the carrier. It sounds a bit brutal but it works a treat.
 

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Just ordered some Rotary Slide Bearings (bushes really) from BMW as at least one of these has failed, giving rear toe changes on the LHS. Had a look at axle carrier and pitman arm bushes - both seem OK. Hopefully this will bring the car back to it's usual best.

Kurt
 

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Discussion Starter #7
Kurt,

I was maybe a bit quick saying everythings now sorted. The back of the cars perfect but I've still not sorted the kickback through the steering and general instability....taking lefthand corners particularly. I'm begining to suspect I've distroyed the upper control arm bush.

These really need to be examined with the car on a ramp. That said the car sailed through its MOT last week. I could have asked the chap to inspect the bushes but its best to do these things after the MOT not during!

I read somewhere on this site that 750/850 control arm bushes can be used instead. They are much stronger and apparently oil filled.

Craig
 

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ECM4 said:
Kurt,

I was maybe a bit quick saying everythings now sorted. The back of the cars perfect but I've still not sorted the kickback through the steering and general instability....taking lefthand corners particularly. I'm begining to suspect I've distroyed the upper control arm bush.

These really need to be examined with the car on a ramp. That said the car sailed through its MOT last week. I could have asked the chap to inspect the bushes but its best to do these things after the MOT not during!

I read somewhere on this site that 750/850 control arm bushes can be used instead. They are much stronger and apparently oil filled.

Craig
Hi!!
Don`t know about the 750/850 bushes. But front end instability can be the result of bad caster arms(the thingy that goes from the chassi(big bush) to the inside of the wheel hub/lower control arm(ball joint)) If these are faulty, the car will be instabile while braking and/or cornering. Mine deteriorated under a short period of time at around 110k miles(original parts,never changed) and the car started pulling at one side when brakes were applied. When standing aside the car when the car was braked down from a low speed, you could actually see the front wheel shifting backwards(result of both bad ball joint AND bush) the arm comes as a complete part with ball joint but the big bush to chassis has to be ordered separately.

:M5thumbs:
Sakke
 

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Discussion Starter #9
DrSakke said:
Hi!!
bad caster arms(the thingy that goes from the chassi(big bush) to the inside of the wheel hub/lower control arm(ball joint))
We're talking about the same thing. I replaced mine not long ago and everything was OK for a while. I suspect the left side bush has failed. I tried very hard to tighten this bush with the weight on the car but it's not easy without a ramp. Get this wrong and the bush doesn't last long.... :sad2:

As you rightly point out the arms come without the bushes which are bespoke M5.

I'm going to search for the post with reference to the 750/850 bushes.
 

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Discussion Starter #10
Standard E34 bushes: 31121136605
E34 M4 bushes: 31122226528
E32 750/850 bushes: 31121136607

all physically the same size.....

....and mine after 3000miles....
 

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ECM4 said:
Standard E34 bushes: 31121136605
E34 M4 bushes: 31122226528
E32 750/850 bushes: 31121136607

all physically the same size.....

....and mine after 3000miles....
One of the differences between standard E34 and M5 bushes is that the hole with the alloy collar is offset in the standard bush, and central in the M5 one.

That's why there's an alignment mark on the bush and the arm.

Obviously it's only a small difference, but I'm sure the geometry is designed the way it is, for a reason...
 

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Discussion Starter #12
........the front of my car's turned to jelly pudding! Surface imperfections send shudders through the car. same effect hitting mid corner bumps. On certain surfaces I'm convinced the nose shakes slightly from side to side. Its a rubbery sensation. I strongly suspect these bushes have gone soft. They seam especailly soft when prodded.
 

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ECM4: Got interested when you mentioned that the bushes are filled with oil? I have a 750 bushing here (bought for my M5), where is the oil in that case? *see pic*



*sorry for the BIG pic...* ouich
 

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It's a common misconception that the 7-series bushes are fluid filled. The only difference as far as I could see when I've looked at them before, is that the bush shown above has a polyurethane strengthener (the green bit), so in theory, they should last longer/be stiffer. I didn't buy them though.

morson1: Can you measure the bush to determine if the hole in the middle is actually central, or is it offset?

Cheers,
Andy
 

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Discussion Starter #16
Andy, you could well be correct. I've just bought two from the stealer (£40 each) and they look similar appart from the insert. I'll let you know the outcome.

My understanding is that the track control arm bushes are oil filled in some way. Maybe this is where the confusion arrises.
 

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ECM4 said:
Andy, you could well be correct. I've just bought two from the stealer (£40 each) and they look similar appart from the insert. I'll let you know the outcome.
My understanding is that the track control arm bushes are oil filled in some way. Maybe this is where the confusion arrises.
As far as I know, the only oil-filled bushes on the M5 are the engine mounts. The E32 7 is the same.

ECM: Can you measure the control arm bush to determine if the hole in the middle is actually central, or if it's offset?
 

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Discussion Starter #18
Andy, I had a good look when I received the bushes and the collars appear central but I have not measured them. I should have asked to see standard bushes :confused3

I'm certain it was the service manager that suggested the lower track arm bushes were oil filled....they certainly look peculiar....
 

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AndyE said:
It's a common misconception that the 7-series bushes are fluid filled. The only difference as far as I could see when I've looked at them before, is that the bush shown above has a polyurethane strengthener (the green bit), so in theory, they should last longer/be stiffer. I didn't buy them though.

morson1: Can you measure the bush to determine if the hole in the middle is actually central, or is it offset?

Cheers,
Andy
The hole is 1 mm offset.
 
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