how can u tell if ur rear shock mounts are ready to for a change - BMW Forum

dementievafan · 09-22-2006, 03:07 PM

i took a pic idk if this does any good

Hamfisted · 09-23-2006, 12:23 AM

It looks like your shock mount is Ok. What you see torn and missing there is the dust boot and foam snubber. Pretty typical on these cars. They sell replacements online and its common to replace them when you replace the rear shocks. You have to pull the shock out of the shock mount to replace them though. Is the dust shield still there below the top of the tire?

-Mike

crazy91318 · 09-23-2006, 04:27 PM

mine started to make a clunking sound when ever I would go over a bump so when I took them out to replace them they fell apart.

toymachine595 · 09-23-2006, 10:50 PM

Ya same thing happened to mine. I started to get clunking over bumps. I took em out and they were pretty shredded and had alot of movement. The hardest part about changing them is just tearin the friggin trunk apart to get to the mount bolts but besides that its worth doin it if youve got any noise back there
peace

Hamfisted · 09-24-2006, 11:45 AM

When I replaced the shocks on my kid's car with Bilsteins I also replaced the upper shock mounts with new "Ground Control" heavy duty urethane mounts, that can be removed from the bottom without going into the trunk. The urethane mount is also tougher than the stock rubber too. The bigger footprint will also spread the shock load out better in the shock tower and keep from tearing the metal.

Ground Control E36 rear shock mounts....

You can also order the foam bump stops from Ground Control too...
Polyurethane Foam Bump Stops

If you need the dust covers you can get them from BavAuto.

-Mike

dementievafan · 09-24-2006, 01:22 PM

thx mike

bitcore · 09-25-2006, 03:39 AM

note: if you get urathane, it transfers more of the force onto the body of the car instead of absorbing very strong transients. What does this mean? On a street car: you will have an increased probability of TEARING the metal around the shock mount, and eventually completely destroying the shock tower. One of the guys on this form or united bimmer had this happen to him - with stock mounts. I totally forget his username but I think it starts with a D... Not delorient.
Stock E46 convertable shock mount + re-enforcement plates are much much much better for a street car.

Oh, and you need new bump-stops, that's the red thing that's all torn up and prevents the shock travel from reaching a 'dead end' if the wheel goes too far upwards and instead provides extra damping towards the end of travel. Looks like you like hitting speed bumps really hard.

Pull that thing down the shock's shaft some and then take a picture of the black rubber, that's what breaks down and fails.

Edit: It's Delmarco who had his shock towers tear completely apart.

Hamfisted · 09-25-2006, 07:52 AM

Delmarco wasn't using Urethane shock mounts, they were just the stock mounts. His bump stops were destroyed and the shock tower metal was just torn loose. His stock mounts were way over due.

-Mike

bitcore · 09-29-2006, 07:19 PM

Quote:

Originally Posted by Hamfisted

Delmarco wasn't using Urethane shock mounts, they were just the stock mounts. His bump stops were destroyed and the shock tower metal was just torn loose. His stock mounts were way over due.
-Mike

Exactly my point. stock mounts, made of rubber, absorb more of the impact than urathane would, and his shock towers still bit the dust. The reason his towers failed is because the rubber failed and probably his bump stops too - this made the impact on the towers much stronger [clunking] and thusly tore the metal. Think about it, What if the shock mount just involved bolting the top of the shock to the tower instead of having a rubber damper in-between the shock and the shock tower? It'd be much more harsh and transfer much more of the impact transients to the metal shock towers. Metal may flex from a dampened force, yet would break\tear from that same impact without any damping.

As I said, get new bump stops and E46 convertable mounts and a re-enforcement plate on the top of the tower where the nuts bolt onto the mount's bolts, and you should be gravey for quite a long time - ontop of that, you'll probably save a considerable amount of cash too.
If you'll take another picture of the shock mount with the bump stop slid down, we can tell you if your current mounts are bad. It can't hurt to replace them anyways but odds are they may be just fine. You do, however, NEED to replace that bump stop. As Mike and I said, this further helps prevent shock tower damage and quick degredation of the mout itself. They are very cheap and you don't even have to compress springs\etc. Just get that side of the car in the air and unbolt a few things and slide the new on on. Cake.

Unless you want to really track & race your car should you worry about preformance (urathane) shock mounts. Besides, if you are investing in preformance shock mounts, you WONT notice the difference unless the rest of your suspension is decked out... And no, not just a fresh set of lowering springs\coilovers, I'm talking about full on stiff stuff - bushing\bearing replacements such as RTA Bearings and LCA eyeballs.