Rear suspension refresh

kyepan

Member
Plan for the weekend

New:
RTABS Standard
RTAB limiters PSB
Rear ARB bushes PSB
Drop links
Upper rear outer ball joint
Lower rear outer bush/ thingy!

Got some tidy tools too.

RTAB tool - not the ebay job from turkey, but a proper one, it's massive and heavy.
The upper and lower bush tool - again a proper one.

Looking forwards to it..
 
The current state of the ropey saggy knackered lower outer bushes
IMG_20200404_164530 2.jpg

The RTABS had quite a bit of movement with only a little lever with a screwdriver, so at 100k miles, i'd imagine they're probably in a similar state.

New fresh bush aplenty - a personal favourite of mine.
IMG_20200408_195835 2.jpg

Plus a shot of the RTAB tool which was - not the cheapest, but available and fast delivery.
 
Said tool

https://www.ebay.co.uk/itm/221610255052

As yet untested - will report back once it's been used in anger.
 
Elapsed time: 5 hours - RTAB bushes changed : 1

I can report back that the tool worked a treat to extract but the thread wasn’t quite long enough to use the conical tube section to compress the bush, and I just used the conical outer section of the arm to put the new bush in.
IMG_20200410_151042.jpg

The old bushes were OEM BMW, not sure on age, and looked in a reasonable state, certainly not breaking apart completely at the centres, however the raised section outside of the bush was coming apart.
IMG_20200410_144344.jpg

The RTAB limiters were a bit of a pain to fit, but went in more easily

Camber positions marked with paint pen, will use white next time.
IMG_20200410_131948.jpg

Straight edge used to reset the rear trailing arm bracket housing thing angle.

The amount of road grot in behind the mudflap and wheel arch trim at the bottom of the back of the sill was quite surprising, that is definitely going to be a place where the cars rust in the future, gave it a thorough clean out.
IMG_20200410_132950.jpg

More today
 
The ARB bushes were INO a waste of time refreshing, but forum advice about the RTAB/RTAL’s is spot on... & changed the @rse from being a dangerous pendulum to a planted tree
 
Following your progress bud. Have also done the rtabs, and planning on changing the other bushes too(once I replace my rear bearings)
 
Bit late but the "Lower rear outer bush/ thingy" can be changed to ball joints - you just use the upper ball joint in its place. The Z4M comes like this as standard.

https://www.pistonheads.com/gassing/topic.asp?h=0&f=47&t=1755842&i=63
 
Jakg said:
Bit late but the "Lower rear outer bush/ thingy" can be changed to ball joints - you just use the upper ball joint in its place. The Z4M comes like this as standard.

https://www.pistonheads.com/gassing/topic.asp?h=0&f=47&t=1755842&i=63
Yes i heard this!!! but yes also too late. :D Next time.

Elapsed time 7 hours - RTAB bushes changed : 2

Second time round this was much easier...
rtab2.jpg

less grot on this side too.
less grot.jpg

However i did note that because there is only a layer of paint as protection, where the toe gets adjusted the paint has worn through, and there is a surface of rust, i think that this could do with a rub down and a lick of primer and paint to protect in the future... another job for another day.


Elapsed time 12 hours - RTAB bushes changed : nearside (RHS) upper and lower outer rear bushes changed

Not having taken this particular cars suspension apart before, I got in a pickle, picking to do the upper bush first, which in hindsight was a mistake on a number of fronts. I first undid the top hub bolt, without first releasing the pressure or removing the spring, the spring then did it's thing and i was a bit stuck for a bit.

The trailing arm had to come back out of the front mounting, after I just re-fitted it, the spring had to come out of the pan to relieve, all of this required some swearing, and a beer courtesy of my wife, who heard we swearing.

The top ball joint had about 4mm of axial play and 2mm lateral play, so really needed doing, was a bit miffed that the cup on the puller didn't quite make contact with the outer race so put pressure on the inner until it moved a bit.
not quite fit.jpg

The top ball joint was also TIGHT, wound it up quite a bit before it started to move.
upper outer out.jpg

Then after that it was already 5pm and the lower bush called me to start it, this was a mistake. I didn’t quite understand how the camber adjustment bolt and washer worked and fitted together. but marked them with my trusty white (chose white today) paint pen, so i knew how they fitted back together. Will get out and get the car aligned properly to CSL settings once we are allowed back out and about.

secondly I could not get the lower arm off the hub for about half an hour. The rear of the bush looked quite bad
IMG_20200411_183943.jpg

The front looked pretty reasonable.
lower front.jpg

And started to loose the light around the time i was refitting the wheelarch trim, which was not playing ball.

Going to do the offside today, and save the ARB and drop links for another weekend.
Also - a local garage agreed to do CSL settings but wanted to charge 150, that sounds like quite a bit...
 
kyepan said:
Also - a local garage agreed to do CSL settings but wanted to charge 150, that sounds like quite a bit...

It would be cheaper to buy me a set of number plates you can have my old ones (Z4M) and swop them on just round the corner and they would do it to Z4M spec and pay a normal alignment fee

Or drive to Simon Thorpe in Grimsby and pay £60 an hour and have whatever settings you want
 
Elapsed time 18 hours - RTAB bushes changed : nearside and offside upper and lower rear bushes changed

Started a bit earlier today as I missed sitting drinking some wine with my wife yesterday evening which she was most miffed about, to be honest so was I.

So today I learned how to get the spring back in without dropping the front of the trailing arm, it involves reading the Haynes manual, ignoring half of it and knowing which half to ignore… the hint here is ignore removing the drive shaft, and don’t ignore undoing both of the anti roll bar linkages so the anti roll bar doesn’t foul on the drive shaft when you try and get the spring back in.

I also learned that buying bush pullers from eBay means you’re dancing with “buy cheap buy twice". More on that later.

Finished the problem with the trim on the other side in about 30 seconds, shows what a night’s rest does to the mind, and some daylight.

Decided to try the lower arm bush first this morning, as it was less involved, worked out the lever points and got that out and in within any major drama.
lower left.jpg

This is how to lever the hub away from the car to get the bottom control arm out, wish I had figured this out yesterday.
lever point.jpg

Managed to get the deep socket on this one, and it came out swimmingly.


My two main worries were: getting enough movement in the trailing arm to clear the upper arm and getting the spring out and back in to help with the former.

lowered the hub a bit more by detaching the strut bottom, make sure you have a jack under it taking the pressure of the spring, or it will ping. :o

Spring came out easy, then the top arm came apart fairly easily, but was struggling for clearance to get the tool on to extract the bush. Eventually realised I needed to disconnect the ARB linkage, which gave me enough space to get the tool on.
spring out.jpg



Here’s were "buy cheap, buy twice" kicked in. Withdrawing the bearing was fine, but after three attempts to insert the new bearing I had to stop for lunch, because it went in on the piss every time.

I’d picked the slightly better bush yesterday, in so far as the cup that drives against the outer shell made contact, this one hit the inner and rotated the spherical bearing, which sent it on the piss as it started to wind in. It was clearly on the wonk. No point winding against something at an angle or it will just strip the rod.
not quite fit.jpg

Out of the toolbox came a 34 and 36mm impact socket for removing 205 hub nuts. 205 hub nuts are like a lottery, depending on what model you have, and what age, it can be anywhere from a 26-28 (I think) for a 1.6, 34, or 36….. for a 1.9, diesel and base models are similarly random.
pugsocket.jpg

The 36 did the job, and cleared the inner shell. The bush of course promptly wound in on the piss just to dash all of my hopes, but then miraculously straightened and we were away.
left upper pug socket.jpg

Getting the spring back in proved a major headache, and eventually after much swearing, the antiroll bar was disconnected on both sides, a spring compressor aided things a bit because i'm a weakling.

Went to drink wine on the terrace after that, in the afternoon sun, with my wife. White wine i might add, for extra weakling points. With a cube of ice, for bonus weaking points.

The anti roll bar bushes and links will have to wait for another weekend. As the retaining nuts need replacing, they are so rusted a 13mm bihex just rotates, only my hex socket set gave any purchase. New set ordrered. I'm also wondering how i'm going to get the car high enough to get it out from underneath. As all the videos show it either on high stands or on a 2 post lift.

.... set of lower spherical bearings... nearly ordered... because geometry stability
 
If you are planning on doing a refresh like this again, always get new bolts. RealOEM lists the sizes and you can pick up a set off each one for a couple of quid on eBay.

I found the rear antiroll-bar bush quite difficult to get on - the standard bolt isn't that long and you really had to compress it to get it started. In the end I swapped it for a longer one and it was way wasier.
 
Good work, I'd love to do mine but space and tools are limited. I think your pictures have convinced me not to try! :lol:

Funny you mention the 205 part lottery. I still remember my ones being a nightmare for working out which parts were needed-it seemed like every year was a 'changeover' year where there was a possibility of several similar, but crucially different parts.
 
Jakg said:
If you are planning on doing a refresh like this again, always get new bolts. RealOEM lists the sizes and you can pick up a set off each one for a couple of quid on eBay.

I found the rear antiroll-bar bush quite difficult to get on - the standard bolt isn't that long and you really had to compress it to get it started. In the end I swapped it for a longer one and it was way wasier.

This is good advice and i agree, next time I will. It's funny you should mention real OEM as that's exactly how i found the ARB nuts, then bought on ebay. What bolt did you end up getting for the ARB? i'll grab some of those too.

The only other bolts i found that were a bit corroded, was the nearside eccentric lower hub bolt (the adjustable one for camber) and a couple of the trailing arm hanger to chassis bolt heads.
Everything else was given a brushdown with the wire brush and copper slip on the faces and shafts.
 
kyepan said:
This is good advice and i agree, next time I will. It's funny you should mention real OEM as that's exactly how i found the ARB nuts, then bought on ebay. What bolt did you end up getting for the ARB? i'll grab some of those too.
M8 / 30mm 8.8 grade - I had these left over from another job on a different car and they worked, didn't choose the size specifically. OE bolts are 16mm.
 
Jakg said:
M8 / 30mm 8.8 grade -
Most appreciated!!! found those and the 43mm ones for the arb drop links on ebay for peanuts :thumbsup:

Also it's worth noting that Real OEM notes the width length, and grade of standard bolts, so you can order the correct length.
Granted it doesn't note the thread pitch / depth / or any threadless shank
 
Back
Top Bottom