[jsunma]

Yes, there are only 2 nuts on the rear shocks. One is inside the car, so that'll come off easy. The other is below the lower shock mount and very much exposed to the elements. From your pics, it seems that you have the standard amount of rust on suspension components, so you MAY have difficulty taking off that lower nut. Some of this also depends on the construction of the shock you are removing. Some have the provision for you to hold the shock with a wrench while you work to remove the lower nut. Some ask that you insert an allen key into the bolt part of the shock while you turn the nut. The latter arrangement usually doesn't work well as the bolt is seized and the slot for the allen key is rusted out.

Since you have purchased lower mounts, if you get truly stuck you can remove the lower mounts - with the shock still bolted to them - from the control arms. Press up, and lift the mount out of the arm. That frees the lower end (and the top won't be a problem). The bolts that hold the strut mounts have a E12 torx head and that goes into a 17mm nut that's embedded into the rubber of the mount. Those lower mount bolts will be hard to remove (rusted) as well, but at least you can get sockets and wrenches onto both sides and eventually work them free and then maneuver the shock assembly out of the car.

(note, IMO if you are removing lower mounts, you definitely want an E12 socket and not try to do the job with a conventional 10mm socket. The last thing you want to end up doing is stripping the head on the mount bolt...because your day is going to get a lot worse from that point. I'm just saying.)

I had to use both heat and the remove the lower mounts procedure to get one of my rear shocks off. But I live in the land of salt and rust. y m m v.

[dmatre]

Originally Posted by clegg

If you've done the OFHG and VCG this is a piece of cake. I would for sure get an alignment after.

Unless you are loosening the bolts to, or replacing one of the suspension links, there is no need to get a new alignment. Replacing the rear shock absorber does not change the alignment at all. You can do it if you think that the pothole hit changed the alignment (if it still drives squirrely after changing the shocks) - but I've bubbled several tires without knocking the car out of alignment.

Replacing the front strut is a completely different situation, and does require an alignment afterward.

If you've purchased the top & bottom mounts, then the easiest way to pull the bottom is to remove the two bolts holding the bottom mount to the suspension arm, and lift the bottom mount out with the shock. Replacing the bottom mount means you don't need to dismount the bottom of the shock from the old mount - throw them out together.

If it's not too late, I'd pick up some rear bump stops (BMW sometimes calls them auxiliary shock absorber), as yours have probably come apart and likely need to be replaced.

When you take the old shock out, lay the parts out on the ground in the order that you remove them (top to bottom) so that you don't make a mistake during reassembly. It's not complicated, but if you get the rubber seal on the wrong side of the top mount, it won't seal and you could have water intrusion.

It'll take you about an hour for the first one, and 15 minutes for the second.

Good luck!

[Willygbr66]

Again thank you for the constructive comments and advice. Decided to go with Koni STR.T struts and sourced the other parts ie. mounts etc through BMW UK parts as the prices were nominal in my opinion compared to other sources.

Will do this all myself and save a few beer tokens for the future.

Keep you guys updated on how it went. Again thank you.

[Willygbr66]

Quick update. Managed to get the rear right strut off yesterday after work. Took about 45 minutes as I was being somewhat meticulous. Plus the pain for whatever reason was trying to get the lower rubber mount out as I am replacing all the separate parts along with the struts. Doing the other side will be a breeze now having the knowledge.

Anyway to cut a long story short my god it was totally destroyed. Clearly the top had corroded hence the clunking sound. When compressing then pulling apart there was brown watering liquid that flew out. Bump stop was disintegrated. How on earth I got that far on it is beyond me plus I only had an MOT three months ago with no advisories.

Unfortunately could not take pictures today due to it raining though will do for reference.

Last point got my Koni’s through the post. Included a small bag which clearly included a new bottom nut however can anyone tell me what this plastic part is for?

As always any comments/suggestions are much appreciated..

[dmatre]

There has been speculation as to what that is, and where it goes.

I installed it on the shock, below the bump stop.

My thought is that it allows smooth rotation when the shock is compressed to where the bump stop is in contact with the shock.

The design from BMW means that the bump stop makes contact early in the shock travel, and it is an integral part of the handling of the car.

That being said, BMW didn't use such a device, and many don't install it when they change shocks.

I'm glad you got this going. I'd love to hear your thoughts on how it handled after the change - especially how it deals with mid-corner bumps.

[jsunma]

Glad to hear you've got it going.

Your shock sounds like the one that blew out on my car. I replaced Koni's with another set of Koni's. My original shocks/struts - sports suspension - only lasted about 75K miles. The replacement Koni's came closer to 100K...but clearly I drove the heck out of them and probably should have replaced them sooner. Anyway, the ones I replaced recently had that plastic washer. I think, like dmatre I installed it on the shock under the bump stop.

[Willygbr66]

Thanks guys. Will place the plastic part on as suggested. Can’t see it will do any harm. As always will keep you posted. Plan to get this done over the weekend.

[Willygbr66]

Well the drama continues. Fitted rear right strut with no problem. Then began on rear left. Got strut out which again was totally dead however have now ran into a problem.

One of the E12 bolts that secure the lower rubber mount is seized. Looks like the nut on the mount itself has come away meaning everything just spins. Tried WD40 etc to no avail.

Anyone have any suggestions as to my next move? Need to replace that mount as it’s beginning to perish.

[dmatre]

Cut the head off of the bolt. The head is below the suspension arm and is easily accessible. Use a grinder (carefully!!!), a Dremel, or a hacksaw. Then you'll need new bolts from BMW, but that's cheap. You can likely find a temporary bolt at a local hardware - until you can get by BMW.

Second option is to remove the bottom nut from the shock, replace the shock & leave the bottom mount in place until you can get the required bolts, then cut the heads off & replace the bottom mount.

[Willygbr66]

Originally Posted by dmatre

Cut the head off of the bolt. The head is below the suspension arm and is easily accessible. Use a grinder (carefully!!!), a Dremel, or a hacksaw. Then you'll need new bolts from BMW, but that's cheap. You can likely find a temporary bolt at a local hardware - until you can get by BMW.

Second option is to remove the bottom nut from the shock, replace the shock & leave the bottom mount in place until you can get the required bolts, then cut the heads off & replace the bottom mount.

Cheers dmatre. That’s what I was thinking. Plus I did as you said and put new strut on.

[jsunma]

Originally Posted by Willygbr66

One of the E12 bolts that secure the lower rubber mount is seized. Looks like the nut on the mount itself has come away meaning everything just spins. Tried WD40 etc to no avail.

By "come away", you mean it's no longer held in the rubber mount? Well, it's not supposed to be really. You need to hold the nut side with a wrench or socket. I believe I said 17mm earlier.

Also, a better penetrate than WD40 might be in order. Do you have PB Blaster over there? Lacking that (or maybe with it) you might want to apply heat. Make sure you spray whatever you're using for a rust penetrate on the nut side so that it can penetrate into the threads that are currently rusted into the nut. I just have to say that I generally avoid cutting anything off unless absolutely necessary because the angles you end up working most of the time make it all to easy to cut something else...which obviously you do not want to do.

And my mounts came with bolts...so I didn't have to worry about messing up the bolt.

[EJOE12345]

Originally Posted by Willygbr66

Hi,

Well when it rains it pours. After having a walnut blast last week and then being told I have a leaking injector, today I took my car for a drive and I definitely believe my rear right shock absorber is now toast. Heard a strange sound at rear of car and on stopping then checking the rear end seems very “bouncy” when pushing down on the boot.

Questions are do I replace both shocks, which many suggest? How difficult a job is it for me personally to do and finally any recommendations on what brand replacements I should get along with do I also get all the mounts etc.

As always suggestions/advice will be much appreciated.

I believe replacing shocks on these are like the E46, and I did them on there. If it's anything similar it's super easy. Jack up the back, unscrew the bottom from the wheel area, unscrew from up top and reassemble the new one with all the extra pieces on the old one (might need a new dust cover or other small pieces), make sure to get a new bottom washer, and then you can throw it back in. That's a really simple instruction guide though lol. Essentially, it's a pretty easy job if you're handy. I bet there are some good YouTube videos on it.

[dmatre]

Originally Posted by jsunma

By "come away", you mean it's no longer held in the rubber mount? Well, it's not supposed to be really. You need to hold the nut side with a wrench or socket. I believe I said 17mm earlier.

Also, a better penetrate than WD40 might be in order. Do you have PB Blaster over there? Lacking that (or maybe with it) you might want to apply heat. Make sure you spray whatever you're using for a rust penetrate on the nut side so that it can penetrate into the threads that are currently rusted into the nut. I just have to say that I generally avoid cutting anything off unless absolutely necessary because the angles you end up working most of the time make it all to easy to cut something else...which obviously you do not want to do.

And my mounts came with bolts...so I didn't have to worry about messing up the bolt.

When I changed my rears, the bolts loosened without needling to resort to a wrench.

But the great thing about this forum is that there are always people with more/different experiences to pull you through when you get stuck.

For sure, using a 17mm wrench to hold the nut is far preferred to cutting the bolt! Thanks for sharing the knowledge!

[Tambohamilton]

Originally Posted by Willygbr66

Quick update. Managed to get the rear right strut off yesterday after work. Took about 45 minutes as I was being somewhat meticulous. Plus the pain for whatever reason was trying to get the lower rubber mount out as I am replacing all the separate parts along with the struts. Doing the other side will be a breeze now having the knowledge.

Anyway to cut a long story short my god it was totally destroyed. Clearly the top had corroded hence the clunking sound. When compressing then pulling apart there was brown watering liquid that flew out. Bump stop was disintegrated. How on earth I got that far on it is beyond me plus I only had an MOT three months ago with no advisories.

Unfortunately could not take pictures today due to it raining though will do for reference.

Last point got my Koni’s through the post. Included a small bag which clearly included a new bottom nut however can anyone tell me what this plastic part is for?

As always any comments/suggestions are much appreciated..

It goes between the foam rubber and washer of the top mount, to firm that up if desired.

[Willygbr66]

Well new update. Damn bolt will not budge. Sourced some PB blaster over here in the UK, been spraying the nut for last two days and it has not made any difference. I can only see the option of cutting it off. Have a new replacement at hand.

Due to the confined space what’s the best option? Angle grinder will not work I know. Hacksaw possibly but that will take forever.

Anyone have a solution please?

[Tambohamilton]

I'd go with hacksaw if you can't get in with the grinder. Just take your time. Failing that, drill the head off the bolt?

Also, though I admit I've never used pb blaster, swarfega duck oil is by far the best penetrant I've ever used. Just a heads-up.

[jsunma]

It's always something, eh?

How close is your nearest general auto mechanic? (over here, I'd be talking about something like a gas station garage, if a independent mechanic wasn't handy) What I'm suggesting is that you get your car over there - assuming you don't have to drive a long distance to get there - and let them have at it. They'll probably use heat and have the car up on a lift...and odds are it'll come off like butter. Then, either have them finish the job with the shock...or if you've managed to get the bolt on the strut itself off, put the new mount on the old shock and go home to finish....or just rethread the now-freed strut mount bolt and drive carefully home and finish it yourself.

These things are tough to do when you're on your back with the car on a jack stand and you don't do it day in and day out.

One thing I've learned over time is that it's a good idea to know when to call off beating on things and have someone else beat on it for a bit.

And ok..3 more ideas. 1) Remember that PB Blaster (or whatever you use to separate rusted parts) works over time. I tend to start the spray down process a day or two BEFORE I need to work on something very rusty. So, if it's been a day since you started trying, go try again. Might just come apart. 2) Be sure to tap (lightly hammer) the nut and bolt after spraying it. Rust buster stuff works better when there's vibration introduced. And finally 3) You can probably apply heat yourself if you have a propane torch (like, for sweating pipes). It's not what a professional/mechanic would use, but if it's what you have, it's worth a shot. Obviously don't do that if you're hinky on the whole heat and flame thing. Nothing wrong with that...that's why there are professionals.

And finally, a hacksaw WILL work (I hacksaw steel bolts all the time, and sway bar end links, etc...), but you have to be able to get the blade in there...and my guess is that if you've not managed to get any slack in the bolt, there's no room to hacksaw it.

[jsunma]

Originally Posted by Tambohamilton

Also, though I admit I've never used pb blaster, swarfega duck oil is by far the best penetrant I've ever used. Just a heads-up.

Swarfega Duck Oil? Geeze, you guys get ALL the best-named products over there.

[Tambohamilton]

I know, I know! It did take me a while to figure out that it's called that because it displaces water (like water off a duck's back)... Swarfega is the brand (not sure if they also exist elsewhere?), but they're also #1 for handwash stuff here.

[jacbo]

Originally Posted by Willygbr66

Well new update. Damn bolt will not budge. Sourced some PB blaster over here in the UK, been spraying the nut for last two days and it has not made any difference. I can only see the option of cutting it off. Have a new replacement at hand.

Due to the confined space what’s the best option? Angle grinder will not work I know. Hacksaw possibly but that will take forever.

Anyone have a solution please?

hacksaw should be fine.

Guy on youtube who works on high mileage bmws (dan silvester) used one of those freeze sprays when he had something seized which works well for him.

you can get them in most diy and car part shops. i find that penetrating sprays don't do much for very seized bolts

[dmatre]

Your 7th photo on page 1 of this post shows the bolt in question.

I think you can get to it with a side grinder or a dremel. Work first on the head above the shoulder, then work on separating the shoulder from the bolt. (But carefully)

[Willygbr66]

Last update. Went to a local mechanic who I use for my mot and he kindly lent me a dremel which took no more than two minutes to cut the affected bolt off. No damage done. Replaced new rubber mount then rear strut and all is well!

On a side note the bulging inner wall on the tyre is due to it delaminating about of a third away around. The guy that took it off to fit my new one says I have a case as he thinks it’s a manufacturing fault.

Again thank you for everyone’s comments, suggestions and advice. It is very much appreciated.