Time to give the z4 suspension some love.
Discussion
So,
We've had an e85 for a year, it's done the french grand prix and back without skipping a beat, it sounds reasonable, goes well, feels like it has bags of potential.
To be honest i'm really not sure about the handling on it, feels ultra vague during the initial body roll. then sort of settles and is okay, until you change line, then again it's a bit wooly. The steering, despite being the electric PAS setup, doesn't feel like the issue.
After doing a lot of reading and speaking to a few e46 owning friends i'vd decided to give the rear end a bit of a refresh.
It's done a hundred thousand miles, so my first port of call will be RTABS, and a few of the outer bushes. Everything is dirt cheap bush wise, love cheap bush. So i'm doing the following.
Have spent an eternity trying to figure out which bushes to buy,
The Real OEM website for those that don't know it, is a total god send.
Especially ARB which would have caught me out straight away, it's not a sport model, but has the sport ARB as an option... so that means 19mm mm rear ARB not 18...... I actually measured it with a vernier.
So the list for the weekend is new:
RTABS Standard meyle z4 - which are the same as M3, and not the same as normal e46
RTAB limiters Problem solving bushes - because of this video.
Rear ARB bushes Problem solving bushes - because super cheap and poly - will last for ever, and actually specify 19mm, which to be honest would have caught me out cross referenceing the standard BMW part number against all the gumph on ebay.
Rear Drop links - cheap as chips from euros.
Upper rear outer ball joint - yet to arrive
Lower rear outer bush/ thingy! - check out the condition of the old one below.
Got some tidy tools too, because i'm without a bench, vice, and to be quite honest if i broke out the blowtorch to burn these bushes out, the local safety brigade would call the fire brigade.
Now onto RTAB tools... not all RTAB tools are equal. there's about 4-5 available, a couple are discontinued by Sealey, and one pattern one is still made, and one home made job from turkey, and an american one like the turkish one, but they're actually kind of hard to find.
Plus they changed the bush design from a semi flanged job, to a compressed thingy, so you need the conincal bit to compress the bush down... anyway..
140 quid later...
And a half way decent but very cheap looking lower bush tool - again a proper one.
Have a squiz at the lower outer bush
and the new ones.
Will report back on progress.
We've had an e85 for a year, it's done the french grand prix and back without skipping a beat, it sounds reasonable, goes well, feels like it has bags of potential.
To be honest i'm really not sure about the handling on it, feels ultra vague during the initial body roll. then sort of settles and is okay, until you change line, then again it's a bit wooly. The steering, despite being the electric PAS setup, doesn't feel like the issue.
After doing a lot of reading and speaking to a few e46 owning friends i'vd decided to give the rear end a bit of a refresh.
It's done a hundred thousand miles, so my first port of call will be RTABS, and a few of the outer bushes. Everything is dirt cheap bush wise, love cheap bush. So i'm doing the following.
Have spent an eternity trying to figure out which bushes to buy,
The Real OEM website for those that don't know it, is a total god send.
Especially ARB which would have caught me out straight away, it's not a sport model, but has the sport ARB as an option... so that means 19mm mm rear ARB not 18...... I actually measured it with a vernier.
So the list for the weekend is new:
RTABS Standard meyle z4 - which are the same as M3, and not the same as normal e46
RTAB limiters Problem solving bushes - because of this video.
Rear ARB bushes Problem solving bushes - because super cheap and poly - will last for ever, and actually specify 19mm, which to be honest would have caught me out cross referenceing the standard BMW part number against all the gumph on ebay.
Rear Drop links - cheap as chips from euros.
Upper rear outer ball joint - yet to arrive
Lower rear outer bush/ thingy! - check out the condition of the old one below.
Got some tidy tools too, because i'm without a bench, vice, and to be quite honest if i broke out the blowtorch to burn these bushes out, the local safety brigade would call the fire brigade.
Now onto RTAB tools... not all RTAB tools are equal. there's about 4-5 available, a couple are discontinued by Sealey, and one pattern one is still made, and one home made job from turkey, and an american one like the turkish one, but they're actually kind of hard to find.
Plus they changed the bush design from a semi flanged job, to a compressed thingy, so you need the conincal bit to compress the bush down... anyway..
140 quid later...
And a half way decent but very cheap looking lower bush tool - again a proper one.
Have a squiz at the lower outer bush
and the new ones.
Will report back on progress.
Good job it is a 4day weekend.
I recently refurbed all the suspension on my wife's E90 330i. OK, I went a bit far and replaced every arm and bush, including sub-frame and diff. 26hrs work using a 2 post lift and all the correct tools!
The bushes and bearings are a right PITA to get out of the rear hub carrier. Best take it off completely, remove caliper and disc, and do it on the bench.
I recently refurbed all the suspension on my wife's E90 330i. OK, I went a bit far and replaced every arm and bush, including sub-frame and diff. 26hrs work using a 2 post lift and all the correct tools!
The bushes and bearings are a right PITA to get out of the rear hub carrier. Best take it off completely, remove caliper and disc, and do it on the bench.
helix402 said:
You can fit a ball joint to the rear hub like the M3 has instead of the bush.
I’ve found the best trailing arm bush is a genuine M3 one. The Meyle stuff doesn’t last long.
Yes someone else mentioned both of these points. What's the advantage of the ball joint over the standard Bush? Less movement? I could not find lemforder bushes until i had already ordered the Meyle. Let's see hoe they do. I’ve found the best trailing arm bush is a genuine M3 one. The Meyle stuff doesn’t last long.
stevesingo said:
Good job it is a 4day weekend.
I recently refurbed all the suspension on my wife's E90 330i. OK, I went a bit far and replaced every arm and bush, including sub-frame and diff. 26hrs work using a 2 post lift and all the correct tools!
The bushes and bearings are a right PITA to get out of the rear hub carrier. Best take it off completely, remove caliper and disc, and do it on the bench.
I gave everything a big douse in WD40 last weekend, I don't have a bench unfortunately, but I do have the proper bearing puller type tools, and plenty of moly grease, hoping they're going to play ball (no pun intended).I recently refurbed all the suspension on my wife's E90 330i. OK, I went a bit far and replaced every arm and bush, including sub-frame and diff. 26hrs work using a 2 post lift and all the correct tools!
The bushes and bearings are a right PITA to get out of the rear hub carrier. Best take it off completely, remove caliper and disc, and do it on the bench.
Still waiting on the top ball joints to land in the post.
kyepan said:
Yes someone else mentioned both of these points. What's the advantage of the ball joint over the standard Bush? Less movement? I could not find lemforder bushes until i had already ordered the Meyle. Let's see hoe they do.
M3 has it so must be better! Afraid my suspension theory knowledge is a bit out of date. 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.
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 and away from the outer race.
The RTAB limiters were a bit of a pain to fit, but went in more easily with some moly grease on them
Camber positions marked with paint pen, will use white next time.
Straight edge used to reset the rear trailing arm bracket housing thing angle before torquing.
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.
More today
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.
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 and away from the outer race.
The RTAB limiters were a bit of a pain to fit, but went in more easily with some moly grease on them
Camber positions marked with paint pen, will use white next time.
Straight edge used to reset the rear trailing arm bracket housing thing angle before torquing.
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.
More today
Elapsed time 7 hours - RTAB bushes changed : 2
Second time round this was much easier...
less grot on this side too.
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.
Thankfully it didn't induce any play into the new ball joint upon insertion.
The top ball joint was also TIGHT, wound it up quite a bit before it started to move.
Please note insertion is much easier than withdrawal.... and plenty of lubricant was used in both situations, including on the rod of the puller (moly grease)
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
The front looked pretty reasonable.
Lining up the bushes for insertion was easier than expected and i didn't get any of them on the piss.
And started to loose the light around the time I was refitting the wheel arch 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...
shalmaneser said:
Have done this most of my BMWs - makes a big difference to handling, although would highly recommend doing ball joints top and bottom next time round!
Tempted to get another set and do them before alignment! you're about the 11th person to mention using the bottom spherical bearings like on the M cars. 
It's not too hard a job to do that those ones...
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.
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.
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.
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.
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.
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.
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.
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
Kyepan,
I feel your pain. I somewhat foresaw all this when I did mine by buying a subframe off ebay less suspension bits, stripping it, blasting and powder coating and fitted new bushes. Bought all the bushes and arms which were fitted and did the job off the car.
I too had struggles with cheap bearing/bush tools.
More wine.
I feel your pain. I somewhat foresaw all this when I did mine by buying a subframe off ebay less suspension bits, stripping it, blasting and powder coating and fitted new bushes. Bought all the bushes and arms which were fitted and did the job off the car.
I too had struggles with cheap bearing/bush tools.
More wine.
helix402 said:
This is what I need to do, been thinking about it all morning, why wouldn't you go for spherical bearings given the option? ... VNH probably, but i can't see it being much worse given they're standard on M3s.Fortuitously - the z4 shares the part number for the RTAB with the e46 M3... so as long as e46 normal bushes aren't bought by mistake, you get M3 stiffness as standard.
A quick rant.
finished doing the rear anti roll bar bushes and drop links last weekend, were quite worn, more on that later.
So i took it to be aligned this morning, asked the garage in advance if i could use M3 CSL settings, which in brief terms, mean about a degree more front camber and about a degree less rear, with very little toe at either end.
Here's the catalogue of errors the place made (which shall remain nameless for the time being) i was under time pressure so left and paid when I wasn't entirely happy, and have subsequently complained once i had my facts straight.
Mistakes
Claiming front camber isn't adjustable even though i told them it was, and told them on email, and then showed them how to do it....
Doing the front toe first
Forgetting to measure the car with weight in the seats hence not being able to dial in enough camber at the front.
Getting weight in the car and then just putting the camber back to where it was so they didn't have to adjust the toe even though it was the same as when i went in and at the very bottom of the spec, half a degree under max.
Not making any sense on the rear camber adjustments whatsoever, and after repeatedly just being asked to even it up, it coming back exactly the same as before, then claiming the arm was bent on the right, but he had too much camber, so that doesn't make sense either, as that would shorten if it was bent, so it ended up being half a degree out side to side.
Then lying flat out that they cant get any more camber on the front, when the whole point was to put more camber on the front (will explain how i know that in a second)
Then trying to say i'd bent the rear arm using a hammer to put the bushes in, I explained i'd used proper pullers.
Felt like I was being lied to, but they used a mixture of saying they've been at this for years and getting a bit miffed when i started asking questions to keep me from just being blunt about their BS. I could tell it was going down hill as soon as i called them on the front camber adjustment, "he's been on the internet, he thinks he knows best".....
They charged £160, which I thought was high for a normal garage and not a specialist of any description.
Asked me if i was happy, I said sort of not really because the point was to get more front camber, but i need to go.
Got home took one bolt off on either strut top to check it's actually at max camber, as i'm sure i saw the machine with sponk loads of camber when they had it at maximum and weight in the car.... and it's right F%£&%£g in the centre of the adjustment, so the lazy s
t just couldn't be bothered to adjust the toe once he'd done it right at the beginning and was just being a lazy st from hence forward.
This is why i do mostly my own spannering (when I am technically able to), and then only use one trusted specialist on the porsche, and my old housemate who's an ex ford master tech for bits when i don't have time or need a press etc.
People with absolutely zero honesty, and lazy arses just infuriate me. You'd think at a time when business is short, they would want to do an extra good job for repeat custom. but no... they don't. i'm tempted to buy a set of gauges and do it my flipping self.
Rant over.
finished doing the rear anti roll bar bushes and drop links last weekend, were quite worn, more on that later.
So i took it to be aligned this morning, asked the garage in advance if i could use M3 CSL settings, which in brief terms, mean about a degree more front camber and about a degree less rear, with very little toe at either end.
Here's the catalogue of errors the place made (which shall remain nameless for the time being) i was under time pressure so left and paid when I wasn't entirely happy, and have subsequently complained once i had my facts straight.
Mistakes
Claiming front camber isn't adjustable even though i told them it was, and told them on email, and then showed them how to do it....
Doing the front toe first
Forgetting to measure the car with weight in the seats hence not being able to dial in enough camber at the front.
Getting weight in the car and then just putting the camber back to where it was so they didn't have to adjust the toe even though it was the same as when i went in and at the very bottom of the spec, half a degree under max.
Not making any sense on the rear camber adjustments whatsoever, and after repeatedly just being asked to even it up, it coming back exactly the same as before, then claiming the arm was bent on the right, but he had too much camber, so that doesn't make sense either, as that would shorten if it was bent, so it ended up being half a degree out side to side.
Then lying flat out that they cant get any more camber on the front, when the whole point was to put more camber on the front (will explain how i know that in a second)
Then trying to say i'd bent the rear arm using a hammer to put the bushes in, I explained i'd used proper pullers.
Felt like I was being lied to, but they used a mixture of saying they've been at this for years and getting a bit miffed when i started asking questions to keep me from just being blunt about their BS. I could tell it was going down hill as soon as i called them on the front camber adjustment, "he's been on the internet, he thinks he knows best".....
They charged £160, which I thought was high for a normal garage and not a specialist of any description.
Asked me if i was happy, I said sort of not really because the point was to get more front camber, but i need to go.
Got home took one bolt off on either strut top to check it's actually at max camber, as i'm sure i saw the machine with sponk loads of camber when they had it at maximum and weight in the car.... and it's right F%£&%£g in the centre of the adjustment, so the lazy s
t just couldn't be bothered to adjust the toe once he'd done it right at the beginning and was just being a lazy st from hence forward.This is why i do mostly my own spannering (when I am technically able to), and then only use one trusted specialist on the porsche, and my old housemate who's an ex ford master tech for bits when i don't have time or need a press etc.
People with absolutely zero honesty, and lazy arses just infuriate me. You'd think at a time when business is short, they would want to do an extra good job for repeat custom. but no... they don't. i'm tempted to buy a set of gauges and do it my flipping self.
Rant over.
Edited by kyepan on Thursday 14th May 18:02
Edited by kyepan on Thursday 14th May 18:04
That is the sad state of affairs of the motor repair and servicing industry. It is not an aspirational career choice for most and they know what they have learnt. Sadly, they have no concept that there is more to learn. Done an apprenticeship and they know all there is to know.
Even when getting tyres fitted, I stand around and when the monkey balances the wheel and settles for 5g, I tell him to get it to zero. They normally just say "you won't feel that mate". To which I normally respond by saying, do you want me to go away with that and come back tomorrow and tell you I can feel a vibration and you will have to jack the car up, take the wheel off and do it again?
There is hope for you.
Buy a digital spirit level, a laser measure and a roll of fishing wire.
Load up the weight in the car.
Set up 4 axle stands around the car with fishing line running front to rear, making sure the stands are a good 1/2m beyond the front and rear.
Adjust the stands to they run parallel to each other and the same distance from the centre of either the front of rear wheels.
Now you have all you need.
I did this when I replaced all the rubber bits on my E90. I then sent it to the dealer for alignment. It was in spec.
Even when getting tyres fitted, I stand around and when the monkey balances the wheel and settles for 5g, I tell him to get it to zero. They normally just say "you won't feel that mate". To which I normally respond by saying, do you want me to go away with that and come back tomorrow and tell you I can feel a vibration and you will have to jack the car up, take the wheel off and do it again?
There is hope for you.
Buy a digital spirit level, a laser measure and a roll of fishing wire.
Load up the weight in the car.
Set up 4 axle stands around the car with fishing line running front to rear, making sure the stands are a good 1/2m beyond the front and rear.
Adjust the stands to they run parallel to each other and the same distance from the centre of either the front of rear wheels.
Now you have all you need.
I did this when I replaced all the rubber bits on my E90. I then sent it to the dealer for alignment. It was in spec.
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