[Beau168]

Hey everyone, relatively new to the forum, with a e93.

I've noticed upon replacing the wheels that the bump stops on the shocks/struts are crumbly and basically non existent.

I've done about 3000 miles so far and no problems, but I'm wondering if theres a potential to do damage? Without the bump stops what limits suspension travel, the shocks? I'm also on sports suspension

Thanks in advance

[neilvan]

Bump stops are there to soften the end of the travel so its not a harsh bottom out at the end of the stroke/travel.

Your car won't catch fire without them but its very much so a good idea to have them. It will be uncomfortable and may shorten the life of your shocks without it (depending on your terrain of course).

[Volasko]

I attempted to DIY a lowering spring perch on my own. It was a frustrating experience that I bailed mid way through, in my haste to put my front strut together I forgot to install my bump stop (driver side). I drove without one for about a few months and absolutely cringed every-time I hit a large bump that bottomed out the travel. I was convinced I was doing permanent alignment damage every time it happen. Not long after I my front shock completely failed and started to leak heavily. I was convinced it was because of the bottoming out damage, maybe it was coincidence but I doubt it.

[max_330i]

Originally Posted by Volasko

I attempted to DIY a lowering spring perch on my own. It was a frustrating experience that I bailed mid way through, in my haste to put my front strut together I forgot to install my bump stop (driver side). I drove without one for about a few months and absolutely cringed every-time I hit a large bump that bottomed out the travel. I was convinced I was doing permanent alignment damage every time it happen. Not long after I my front shock completely failed and started to leak heavily. I was convinced it was because of the bottoming out damage, maybe it was coincidence but I doubt it.

Yikes. I destroyed a shock over a rain-filled pothole last winter, and when I removed it, I saw the bump stop had disintegrated to dust even before that hard impact. You are probably right that the lack of bump stop is rough on the car.

[gbalthrop]

Originally Posted by Beau168

I've noticed upon replacing the wheels that the bump stops on the shocks/struts are crumbly and basically non existent. I've done about 3000 miles so far and no problems, but I'm wondering if theres a potential to do damage? Without the bump stops what limits suspension travel, the shocks?

Ever heard about the complaints of "Pothole Explosion"? You only need the Strut Bumper to prevent the metal-to-metal "Explosion" that results when you hit a pothole. It can't do either your strut or your dental work any good to have that "Explosion."

Strut Bumpers are a LOT cheaper than new struts: $10.30 ea. for Febi Bilstein & $20.45 ea. for Genuine BMW:
https://www.autohausaz.com/pn/FB-31336777636
https://www.getbmwparts.com/oem-part...er-31336777636

Those are BMW part# 31336777636 which is correct for my 328xi E91. You should check RealOEM.com to get the correct part# for your E93 335i.

Of course the lower profile tire/larger dia wheel you have, the MORE severe the rebound, as well as potential damage to the wheel by the pothole.

ANYONE have a good, easy method on how to inspect those Bumpers (I assume just jack the body on that corner, let the wheel hang down & use a mechanic's mirror & light if necessary to see up the strut shaft under the dust cover)?

George

[e91Owner]

Reviving this thread as mine are completely dust. Has anyone successfully gotten a lasting solution by cutting the bumper and and sealing the cut with foam glue or another flexible adhesive safe for foam? Given I put 1000 mostly highway miles on my car a year, removing the strut solely for the purpose of replacing the bumper seems like an excessive amount of labor... not to mention the accompanying alignment thereafter.

[dav9515]

if the bump stops are that bad maybe your strut mounts could use a replacement also

[e91Owner]

The strut mounts, to the extent that they matter are fine; The foam (as opposed to rubber or some other elastomer) design on these just degrades over time and they are now 14 years old. I may just give the cut and glue method a try. Worth a shot-they are cheap.

[mainbearing]

I suppose you can order replacement bumpers, cut them in half, then glue them back onto the strut rod. Not sure if the glued part can handle the impact, but if it fails it will be visible.

If that does not work then just pull the struts to replace them (or even with complete assemblies from Rock Auto). If just to avoid pothole explosions and the damages those can cause.

https://www.rockauto.com/en/catalog/...assembly,15174

[e91Owner]

Originally Posted by mainbearing

I suppose you can order replacement bumpers, cut them in half, then glue them back onto the strut rod. Not sure if the glued part can handle the impact, but if it fails it will be visible.

If that does not work then just pull the struts to replace them (or even with complete assemblies from Rock Auto). If just to avoid pothole explosions and the damages those can cause.

https://www.rockauto.com/en/catalog/bmw,2011,335i,3.0l+l6+turbocharged,1446237,suspens ion,shock+/+strut+&+coil+spring+assembly,15174

You sure love Rockauto😅. The struts themselves are fine. I’m just annoyed that their removal requires an alignment otherwise I would just do that. Replacing an $8 part in my brain shouldn’t cause a $100 repair that I can’t do myself… at least easily. In any case, the front rotors started pulsing so when I order a new set from FCP, I’ll order the bump stops as well to be cut.

[mainbearing]

Yes I do, Rock Auto, RM European or Tischer BMW (now BMW of Silver Spring). I bought FCP a few times and did not like the look of the parts I received. I am not sure where they source their parts but some looked like clearance stocks in crumbly boxes (which Rock Auto also offers).

If gluing bump stops work then why not. Maybe wrap a tie wrap around it too like some bump stops have a thick, hard rubber band around.

The struts and shocks are probably worn by now too. I do not know BMW sourced these bump stops, they are junk and do not hold up, like the factory OPG, VCG and OFHG.

[krhodes1]

Originally Posted by mainbearing

Yes I do, Rock Auto, RM European or Tischer BMW (now BMW of Silver Spring). I bought FCP a few times and did not like the look of the parts I received. I am not sure where they source their parts but some looked like clearance stocks in crumbly boxes (which Rock Auto also offers).

If gluing bump stops work then why not. Maybe wrap a tie wrap around it too like some bump stops have a thick, hard rubber band around.

The struts and shocks are probably worn by now too. I do not know BMW sourced these bump stops, they are junk and do not hold up, like the factory OPG, VCG and OFHG.

How long do you expect them to last? My car is now 14.5 years old and sure, the bump stops are crumbly and probably need to be replaced. But come on, be realistic!

If you want a car where you never have to replace suspension components, buy a Toyota Camry. But it will drive like a Toyota Camry, not a BMW.

[AWD Addict]

Replace broken and worn parts on your automobile.

[konstat]

When I went to change my rear struts (blown) I realized my bump stops were completely missing. Granted previous owner never serviced the rear suspension and car is a 2008...

[e91Owner]

Just to follow-up, the cut and glue bump-stop method worked like a champ and took all of about 5 minutes to do. Definitely worth the $8/side if they fail in a year as opposed to hours spent removing the strut and the subsequent alignment.

[TekkaMaki]

Originally Posted by e91Owner

Just to follow-up, the cut and glue bump-stop method worked like a champ and took all of about 5 minutes to do. Definitely worth the $8/side if they fail in a year as opposed to hours spent removing the strut and the subsequent alignment.

What glue did you use? What part did you use? Did you zip tie them together when gluing?
Thanks

[e91Owner]

Originally Posted by TekkaMaki

What glue did you use? What part did you use? Did you zip tie them together when gluing?
Thanks

I used flexible cyanoacrylate (super glue). I did use a zip tie near the top, but the glue dried fast enough to where if you glue it in sections from the bottom up, you can just hold it together with your hands. Then apply the glue on the next section, pinch and repeat. The only reason I used the zip tie was for the last indentation near the top. It is much tighter to the strut there. There is a lot of slack near the bottom.