mrsystems

I'm curious if anyone out there knows how important it is to have my front struts rubber bump stop bushings in good shape? I am not the type that likes to let the car go without anything, ever, but i'm wondering are these needed for only severely bad roads that really jam the shocks or if i'm traveling around town and not hitting the bumps fast can i go without them for a while? Every 993 i've owned has needed these, they are rubber so of course they break down over time but well there it is, thats my question. I've never heard the car bottom out or make any terrible sound that leads me to believe these are more of a precautionary item but i'm not a mechanic and could be dead wrong? Thanks.

Stealth 993

You are talking about the round foam piece that is on the shock piston? They should be protected by the dust cover, & really should last a very, very long time. I would say, if you are not swapping out shocks, to not worry about them.

With stock shocks, you should never really hit the bump stops unless you hit a huge bump, or go to fast over bumps. I just swapped out my US M030 kit for ROW M030 my bump stocks looked brand new. Were just swapped over to the new shocks.

What makes you think yours need to be replaced? Chances are your shocks are blown, not the bump stops.

mrsystems

Hey Mike no not foam definitely rubber here's a link to see the part:
http://www.pelicanparts.com/cgi-bin/...30%2D%39%38%29 long link eh? Mine are original shocks/bump stops with 44K miles on them, was going to upgrade to Bilstein HDs but decided to hold off on that, anyways i'm likely gonna just replace them because mine are shot. I figured what you said to be the case that they are needed for going fast over large bumps, one never knows when a large bump is coming down the road....

Stealth 993

Why do you think the bump stops are shot, & what made you think of replacing them?

The only job of the bump stops is to help cushion the shock when it's about to bottom out. It add a bit of of progressive spring rate. Under 95% of most driving they are never used. On stock US ride height, I'm guessing unless you get air, never used.

I just did this a couple of months ago, they are a foam. No solid rubber. Maybe a foam rubber? I doubt they need replacing. It's really cost prohibitive to replace just the bump stops. You need to remove the shock, disassemble the shock, then swap the stop, reinstall. Lastly, get a wheel alignment. I can almost guarantee, once you pull out the shocks, you will find out they need to be replaced.

My car has over 100,000mi on the shocks, the bump stops were perfect. In all my time wrenching on cars, they usually are in good shape, not replaced when swapping shocks.

You might be able to lift the car, remove the tire, put the suspension in full droop (remove sway bar end link) push up the dust cover. You should be able to see the bump stop.

In the pic you can see the shock assembled out of the car, so you can see what I'm talking about. Sadly, I didn't do any pics of the bump stops.

James Tennier

Noticed one front shock bump stop (foam like material) completely disfigured as if it might fall to the road any day now. Curious...

Cupcar

If bumper that bad, in need of replacement IMHO. They are necessary to keep the spring rate from going to infinity - as in instantly - as well as to protect internal shock parts. If that bad, the shocks are probably shot as well anyway and worth changing at same time.

bcameron59

They are a dense foam rubber inside, though the outer skin makes them look solid they aren't dense or heavy enough to be solid.

They do break down, this one had 122K miles when replaced during new shock install.

As mentioned by others, I would not omit them. If shock bottoms out due to heavy hit, the bump stops would help prevent damage.

myflat6

Replacing my front struts now and noticed my stops were totally disintegrating. Ordering them for $14 each from Sunset Porsche. Pretty cheap for factory parts.

Jason @ Paragon Products

They live in a harsh environment. Not uncommon for them to be deteriorated or in some cases gone completely. They protect your strut and they're cheap so I'd consider replacing them when you install new struts.

pp000830

When I put on the H&R coilover kit the H&R tech line said not to use them with their kit. Be sure your aftermarket struts are intended to be used with them.

Jason @ Paragon Products

Some shocks will have an internal bump rubber and that's fine, but if yours use an external bump rubber, and they're deteriorated you'll want to replace them.