[pjr710]

I like to prep as much as I can before a job and not get met with any surprises.

I've read up and watched a few DIY's on doing this job and it doesn't seem too bad.

I am wondering if anyone has any words of wisdom they can share when doing this job.

The main things I'm not 100% sure on are:
1. if I need any special tools (i was going to get a cheap spring compressor from amazon, but are there other special tools i might need?)
2. I didn't see anyone really torque anything down, are there torque specs?
3. I am not 100% clear on which elements aside from the shock or strut I should replace. Bump stops? The Mounts? I like to just get wearables out of the way because I like to just touch things once and not have to go back and change it out later.

[PerfectAce]

Using one of these strut compressor tools makes the job so much easier: https://www.eastwood.com/fairmount-t...ompressor.html You can find comparable ones on Amazon for about the same price.

You can use (and countless people have) those spring compressor tools available for loan at AutoZone to get the job done. However, if you value your time and sanity like I do, this makes the swapping of springs from old strut to new a 10-minute piece of cake.

This tool is also helpful in spreading the pinch collar on the steering knuckle: https://www.amazon.com/CTA-Tools-400.../dp/B015Q1JNIM

A set of pass-through sockets and long arm metric allen keys will make your life much easier when doing this job. An impact gun will definitely speed things up, but isn't essential.

A few pages from the Bentley manual are attached for referencing torque values.

As far as replacement parts go, you'll need: new rear shocks (2), new front struts (2), new strut mounts (2), new strut bump stops (2), new rear shock mounting kit. You can probably reuse the upper and lower rubber spring pads on the struts as well as the dust boots, but you may want to pick up some cheap ones for peace of mind and return them if not needed.

[SnapCoupe]

Originally Posted by pjr710

I like to prep as much as I can before a job and not get met with any surprises.

I've read up and watched a few DIY's on doing this job and it doesn't seem too bad.

I am wondering if anyone has any words of wisdom they can share when doing this job.

The main things I'm not 100% sure on are:
1. if I need any special tools (i was going to get a cheap spring compressor from amazon, but are there other special tools i might need?)
2. I didn't see anyone really torque anything down, are there torque specs?
3. I am not 100% clear on which elements aside from the shock or strut I should replace. Bump stops? The Mounts? I like to just get wearables out of the way because I like to just touch things once and not have to go back and change it out later.

Are you going to be replacing just the shocks/struts? Or will you be replacing the springs as well? When I installed my ST coilovers, it was far less labor intensive to pre-assemble the new suspension with the shock mounts, etc and throw them right in. This is compared to using a spring compressor and taking the old setup apart and then assembling and installing the new suspension. You may end up paying a bit more for misc parts/mounts (which should be replaced anyway) but you end up saving on time/labor in the end.

[Volasko]

Originally Posted by PerfectAce

Using one of these strut compressor tools makes the job so much easier: https://www.eastwood.com/fairmount-t...ompressor.html You can find comparable ones on Amazon for about the same price.

You can use (and countless people have) those spring compressor tools available for loan at AutoZone to get the job done. However, if you value your time and sanity like I do, this makes the swapping of springs from old strut to new a 10-minute piece of cake.

This tool is also helpful in spreading the pinch collar on the steering knuckle: https://www.amazon.com/CTA-Tools-400.../dp/B015Q1JNIM

A set of pass-through sockets and long arm metric allen keys will make your life much easier when doing this job. An impact gun will definitely speed things up, but isn't essential.

A few pages from the Bentley manual are attached for referencing torque values.

As far as replacement parts go, you'll need: new rear shocks (2), new front struts (2), new strut mounts (2), new strut bump stops (2), new rear shock mounting kit. You can probably reuse the upper and lower rubber spring pads on the struts as well as the dust boots, but you may want to pick up some cheap ones for peace of mind and return them if not needed.

Quality response right here!

While were on the discussion do you recommend a flexible pipe strap to hold the strut shaft in place from compressing into the strut body once you remove the top nut? I remember trying to replace my upper mounts once as a DIY and found the shaft compressed way more into the body that I could compress the springs. I used a crappy spring clamp from autozone - something I DO NOT RECOMMEND - and remember never wanting to DIY that ever again. That spring compressor looks much better.

[sabino56]

I just replaced struts on my E90 base suspension for first time.
Definitely replace strut mounts. Also recommend getting rubber spring pads, sealing gasket, bump stop & bellows. All this stuff is cheap and since it's a big job, better to replace than have to go back in for that stuff. There are also nuts which shop manuals say should be replaced. They are cheap too, so I got those also.

This link is good for repair instructions and torque specs https://www.newtis.info
This link is good for finding names/part numbers of things you want to replace http://www.realoem.com/bmw/ There are a lot of variations on part numbers, it helps to get under car and write down/take pictures of PNs of strut or whatever.

The things I found helpful, wish I had done, or had problems doing
- I put a std spring compressor on the spring with suspension loaded to shorten the length of strut a bit when removing. Just put on hand tight. also provides nice handles to grab to wrestle strut from car

- I wish I had taped up, protected paint around fender opening. it's not a simple, lift the strut out of the car thing - nice to have some protection on paint

- I've read people can get strut out without disconnecting wishbone strut. But sounded like you have to really stress the bushing down to do so. I decided to remove the ball end like the repair instructions said was possible when removing the whole carrier. I found it impossible to get the ball joint out. It was loose but I didn't have strength or weight to pull it down and out of carrier laying on back with car on jack stands. Jacking up wheel loaded it and also was impossible to move. I ended up loosening bushing bolt on frame and then it was easy. There was plenty of play in carrier position to get the strut past vendor without massive force on things. If you remove bolt on wishbone strut it says you should replace those bolts as I think they are tension to yield type of thing (ie. a torque and then 90 deg more). You have to tighten it with the suspension loaded.

- you need something to support carrier after removing strut. I found a cargo strap over chassis stiffener where strut is located and around carrier worked for me

- a simple, cheap spreader - a 3in bolt (I think i got a 7/16) has a 7-8mm shank. Cut off threaded portion and grind down one side until it fits into opening. Then just rotate in slot to spread. It's small and doesn't get in the way while you're messing with trying to get the strut out.

- I read many people use the std strut spring compressors. You have to put it on the top hat/upper spring plate. There is no positive retention there and while I was tightening the compressor, things started twisting & moving and it freaked me out. I was afraid to trust that something wouldn't slip. Since I was committed and had to get it done that weekend, I made a holder with positive retention. Easy to do if you have a welder - if not, I'd get a spring compressor which has a more positive retention on upper spring plate. Only problem I had with the jig was the spring compressor screw wasn't long enough to get on spring at a point to compress enough to get nut on end of strut shaft. I needed about 1 more inch to get spring compressor on spring at a point which would provide enough compression. I could only compress the spring about 1/2 inch by hand. I ended up renting another spring compressor to get the inch & then it worked great.

[PerfectAce]

Originally Posted by Volasko

While were on the discussion do you recommend a flexible pipe strap to hold the strut shaft in place from compressing into the strut body once you remove the top nut? I remember trying to replace my upper mounts once as a DIY and found the shaft compressed way more into the body that I could compress the springs. I used a crappy spring clamp from autozone - something I DO NOT RECOMMEND - and remember never wanting to DIY that ever again. That spring compressor looks much better.

Using a compressor like the one I linked to above will get you enough compression that you don't have to prevent retraction of the shaft so as to be able to thread on the retaining nut. In fact, that was the whole reason I bought the tool. Numerous folks have struggled with getting enough compression using those rental tools, and those working on sport suspension have found it to be damn near impossible using them.

Additionally, using those Autozone cheapies (which I've used on other vehicles in the past) make me more nervous than a long-tailed cat in a room full of rocking chairs.

[6ixSpd]

I've never had issues getting the springs to compress enough using those Autozone type compressors. In fact I DIY'd both front strut mounts on my H&R+Koni front end in a little over an hour wheels up to wheels down.

Trick to take the compressed strut/spring assembly out is to turn the wheel the opposite direction, then push down on the bottom and swing it out from the fender. Sometimes it's close, and it helps to rotate the strut mount to get it out bit by bit. Definitely protect the fender's paint!

[pjr710]

First off these responses are fantastic thanks everyone for the tips. I haven't had a ton of time to really dig in as i've been real busy.

First thing I actually have to do is inspect my shocks (as i said bmw said they thought my rear was leaking oil).

If that's the case and if my fronts are fine .. is it OK if i just replaced both rears?

[PerfectAce]

It's not gonna hurt anything if you just replace the shocks, but your car will have some weird road holding characteristics. Given the age and mileage of your car, it's a pretty safe bet that your struts could use replacement and doing so would improve ride quality and handling. Your struts might not show any obvious signs of failure, but they're likely worn to the point that they're not providing adequate dampening.

When I replaced my struts at 112k miles, there was no obvious sign of failure. But once I pulled them from the car and manually compressed them by hand, I found that the piston rebound was way, way slower (nearly non-existent) than the new replacement parts.

A good mantra to remember when it comes to maintenance on BMWs: cheaping out now means paying more later.

[pjr710]

Originally Posted by PerfectAce

It's not gonna hurt anything if you just replace the shocks, but your car will have some weird road holding characteristics. Given the age and mileage of your car, it's a pretty safe bet that your struts could use replacement and doing so would improve ride quality and handling. Your struts might not show any obvious signs of failure, but they're likely worn to the point that they're not providing adequate dampening.

When I replaced my struts at 112k miles, there was no obvious sign of failure. But once I pulled them from the car and manually compressed them by hand, I found that the piston rebound was way, way slower (nearly non-existent) than the new replacement parts.

A good mantra to remember when it comes to maintenance on BMWs: cheaping out now means paying more later.

fair enough ... when you replaced them did you notice a difference in the way the car felt?

[PerfectAce]

In a word: yes. But the answer is a little more complicated than that. In 80-90% of driving situations, there is no appreciable difference. By replacing worn shocks and struts with new, you're not altering the suspension geometry, or changing the center of gravity of the vehicle, or putting on wider/stickier tires to get more grip, so you're really not gonna feel much difference in how the car behaves just driving to the store to get milk and eggs.

However, when driving the car in less-than-normal conditions, you begin to notice that the car feels more planted and is easier and more predictable to control. For example, when hitting an undulation on the highway at 85 mph, the vague loss-of-control sense is gone -- the dampers are working as intended to push the wheels back to the ground to maintain grip. Or when it's slightly raining and the roads are greasy, and I take a corner with a change in elevation and a little too much throttle, I can confidently predict how the car is going to react even if the rear end is stepping out a bit.

I can't take speed bumps any faster than I could before. I can still feel lane reflectors when driving over them. Potholes are the same hazard that they've always been. My car still has sport suspension and run-flat tires -- spring rates, ride height and sidewall pliability haven't changed enough to turn it from a sports sedan into either a Rolls-Royce or hill climb racer.

[pjr710]

Originally Posted by PerfectAce

A set of pass-through sockets and long arm metric allen keys will make your life much easier when doing this job..

Where do you end up using these?

[PerfectAce]

Originally Posted by pjr710

Where do you end up using these?

For both the struts and shocks, in order to get the retaining nuts on/off the shafts, you have to hold the shaft in place with an allen wrench to keep it from spinning. This picture explains it better than I can put into words:

On the rear shocks, you could pass the allen wrench through a box wrench to get the job done (slowly), but on the struts, because the nut is recessed into the strut mount, you need a socket. There's a very specific socket that you can use for this job: https://www.amazon.com/Schwaben-0030.../dp/B01DFMVFF8 but why pay for that one size socket when you can buy a whole set of pass-through sockets for less ($16 at harbor freight) that can do the job just as well?

[pjr710]

Got it. Never thought of these pass through sockets but i think it’s certtainly something i will be purchasing.

I also looked at that compressor. That’s the one you have? No issues?

[PerfectAce]

Originally Posted by pjr710

I also looked at that compressor. That’s the one you have? No issues?

Same one, well it looks identical anyway. I bought some no-name Chinesium one off Amazon. The one sold by Eastwood is probably made in the same sweatshop. Works like a champ though.

[pjr710]

Originally Posted by PerfectAce

Same one, well it looks identical anyway. I bought some no-name Chinesium one off Amazon. The one sold by Eastwood is probably made in the same sweatshop. Works like a champ though.

Ok great. I think one last question. What about bolts? Bentley says change em, worth changing?

I’m guessing i will likely do this job. Inspect my bushings. Then likely get to some kind of bushing job this spring or summer.

Also i need an alignment after doing my front struts right?

I really appreciate ur help!

[sabino56]

for the nut on top of the strut - you can also use a 13/16 spark plug socket, the kind that has a hex nut cast into the top of the socket. You can put the allen wrench thru the end and use a wrench on the socket. about $4-5 at Ace or autozone.

[PerfectAce]

Originally Posted by pjr710

Ok great. I think one last question. What about bolts? Bentley says change em, worth changing?

I’m guessing i will likely do this job. Inspect my bushings. Then likely get to some kind of bushing job this spring or summer.

Also i need an alignment after doing my front struts right?

I really appreciate ur help!

There are some people that swear that you have to replace every fastener every time you remove it. For certain things, yes, you must replace them (e.g. head bolts, stretch bolts). If the fastener is somehow damaged, corroded or otherwise fucked, then sure, common sense dictates replacement. There's no fastener in this job that, in my opinion, requires replacement. (Although you'll get new nylon-insert lock nuts with what ever struts you buy.) Just keep some blue loctite handy for any fastener you have doubts about.

As far as an alignment goes, I would wait until you replace your control arms/bushings before doing it. Some mechanics will swear that you need an alignment after replacing struts. These are usually the same mechanics that make money performing alignments...whether they're needed or not. Caster is non-adjustable on our cars, so that ain't gonna change. Camber is set using the alignment pin on the strut mount, so as long as you're installing the right part into your car, haven't removed the centering pin (or drilled out the alignment hole) then you'll be go to go (or near enough as makes no difference.) Even if you remove the centering pins, you're gonna get what -- half a degree of negative camber? Oh, the humanity! And as far as toe goes, well you shouldn't be changing the length of your tie rods to replace the struts. Long story short: if your alignment is good (or good enough) before strut replacement, as long as you don't do anything bone-headed, it'll be fine afterwards. Save your money and wait until you replace control arms, tie rods, and bushings before throwing money away on an alignment. Or if you're really paranoid, pay for one of them lifetime jobs, so you don't have to pay a second time.

[bsmoov]

I had a e91 shipped from the East Coast and the suspension was rusted as hell.

The pinch bolt head snapped on me, smh. The nut came off easily, but the bolt itself was seized in with rust and the head snapped clean off.

Seeing that you're from the EC, it can possibly happen to you as well.

Worst feeling ever. Couldnt even hammer it out and it was literally seized in there with rust. Was going to drill it out because i knew extracting it wasn't going to move it for sure. Then I randomly stumbled upon a passat forum and those cars seem to have the same issue with their pinch bolts and what they did and what I did was USE THE NUT ON THE THREADED SIDE AND TIGHTEN IT WITH AN IMPACT GUN. Tightening it sucked the headless bolt right out.


*Oh yeah lol remember that the left and right struts are side specific. I totally forgot and did the reinstall and wasted time as the endlink bolt attachment on the actual strut was backwards (due to it being on the wrong side). Also remember to reinstall the brake line bracket when you're reinstalling the pinch bolt.

[pjr710]

Originally Posted by PerfectAce

There are some people that swear that you have to replace every fastener every time you remove it. For certain things, yes, you must replace them (e.g. head bolts, stretch bolts). If the fastener is somehow damaged, corroded or otherwise fucked, then sure, common sense dictates replacement. There's no fastener in this job that, in my opinion, requires replacement. (Although you'll get new nylon-insert lock nuts with what ever struts you buy.) Just keep some blue loctite handy for any fastener you have doubts about.

As far as an alignment goes, I would wait until you replace your control arms/bushings before doing it. Some mechanics will swear that you need an alignment after replacing struts. These are usually the same mechanics that make money performing alignments...whether they're needed or not. Caster is non-adjustable on our cars, so that ain't gonna change. Camber is set using the alignment pin on the strut mount, so as long as you're installing the right part into your car, haven't removed the centering pin (or drilled out the alignment hole) then you'll be go to go (or near enough as makes no difference.) Even if you remove the centering pins, you're gonna get what -- half a degree of negative camber? Oh, the humanity! And as far as toe goes, well you shouldn't be changing the length of your tie rods to replace the struts. Long story short: if your alignment is good (or good enough) before strut replacement, as long as you don't do anything bone-headed, it'll be fine afterwards. Save your money and wait until you replace control arms, tie rods, and bushings before throwing money away on an alignment. Or if you're really paranoid, pay for one of them lifetime jobs, so you don't have to pay a second time.

Very amazing advice again.

Does your opinion still hold true if you “loosen” the control arm? I was watching the bav auto DIY and that’s what they did on the fronts.

[PerfectAce]

Originally Posted by pjr710

Very amazing advice again.

Does your opinion still hold true if you “loosen” the control arm? I was watching the bav auto DIY and that’s what they did on the fronts.

Yep. No need to replace unless damaged. The bavauto video is good, the only thing I do differently is NOT use a screwdriver to spread the strut pinch collar. There are also videos by autodoc.co.uk on YouTube that are good references for e9x suspension work.

[sabino56]

Originally Posted by pjr710

Very amazing advice again.

Does your opinion still hold true if you “loosen” the control arm? I was watching the bav auto DIY and that’s what they did on the fronts.

I have same question. I loosened control arm to release pressure on ball joint end so I could drop it out of spindle. I don’t see any adjustability in the control arm. The bolt is not eccentric, nothing on ball joint end either. I’ve seen people say you should do an alignment after messing with control arm or tension arm but don’t see why? Or how? Perhaps i’m Missing something.