Sputnik

Hi all,

I've just curious what could be the symptoms of shot OEM shocks?
My car has 37.7K miles on odometer. Should I suspect my shocks are dead? May be it is time for for Mr. Bilstein?.... AJUSA has some special deal on them right at this moment. I just would like to make sure the shocks really need the replacement.
Thanks in advance!

Phil

the first symptom........37.7k miles......
but don't be sad.......its just time to upgrade.....

Sputnik

I am not sad! I just need a reason!

1999Porsche911

Your shocks should last for the life of your car. This is particularly true of your car because of the short throw of the struts. One symptom of a bad shock is continued bouncing after hitting a bump. You should be able to press down on the corner of your car and the car should spring back up with no bouncing.

Robert Henriksen

Phil

"your shocks should last for the life of your car"....
Huh?
could you please explain that?....

viperbob

These cars have shocks that last about 5 years. After this, regardless of mileage, the seals seem to start leaking. It is slow so you do not really notice it. I have installed 50+ suspensions on 993s this past year, and to a number there was maybe one that the rear shocks were in fair shape. The rest, even a '98 with 6K miles, were bad. Thr fronts seem to be worse in most cases. No bump stopping capability (you can instantly compress it with your hands) and usually no or maybe a little rebound. This is also validated with the drivers after the install that notice a smoother yet more predictable ride...

mleds

The difference was immense on my car. I am so glad I replaced the factory shocks with the Bilstien HD's. The car is just awesome now.

DJ

I don't think so. If Porsche expected them to last that long, why do they consider them a "wear-item", in the same category as brake pads, windshield wiper blades, tires... Do you expect your tires to last the life of your car? How about your oil? I have a pretty fair amount of experience in at least several dozen 993s, and could notice a substantial amount of wear on the shocks of EVERY one that had over 20k miles. On my personal 993, I could feel more wear than I wanted to tolerate at 10k miles.

Shocks wear very slowly, and gradually get worse and worse. If you don't know what it's supposed to feel like, then you likely won't notice the slow degradation until it's really bad. By that time, most have driven their cars for thousands (if not tens of thousands) of miles with bad (worn out) shocks, suffering from a bad ride, and poor handling.

I'm not an engineer, so I probably don't understand all the physical forces at work. Can you explain this to me?

Yes, this test is very much like using visual inspection on a tire that is completely shredded off the rim. If you can see the holes where all the air fell out, then it's likely that it's time to replace that tire. A shock that allows the car to continue bouncing after you push down on the fender has been wore out for a very, very long time (and it should have been replaced thousands--if not tens of thousands--of miles ago).


At 37k miles, I will bet the price of your car that your shocks are wore out. Do they need to be replaced? No, of course not. You don't ever need to replace your tires either, nor your brake pads, wiper blades, or oil, but it's much more enjoyable to drive the car if you do.

Radar

So, are you saying that a shock should be good until its seals start leaking? I guess I've been throwing a lot of money away for years. I always replace my OEM shocks as soon as I notice handling degradation. Almost always that happens a lot sooner than 5 years and with no apparent leaks.

TheOtherEric

I think the guys with experience answered the question (excluding the comment that "shocks should last for the life of your car" of course)

As an anecdote, I found that my '96 needed new shocks at 40k miles. I didn't find the press-on-the-bumper test to be useful, as the shocks had enough to prevent continued oscillations. But the ride quality was quite obviously terrible, and that's the real test. Very jarring. It was confirmed when I installed new (slightly used) shocks.

Georges Rebeiz

Here in Lebanon , you can expect your shocks to be inspected yearly by the MOT. There are special machines whereas the car is placed on special springs and then the floor under the tyres starts vibrating and then you get a reading for each shock and the normal reading should be within two variables. If it is less then you need to change the shocks else the car does not pass the test.

Do you not have these kinds of Machines in the US. I am sure you do

Dr. No

We do. They are called "potholes."

Actually, you'd be surprised at the rolling disasters that are free to exceed the speed limit here. We need a TUV.

Joe S.

My rear shocks started leaking when they were 5 years old and had only 12k miles on them.

deltawedge

As far as shock construction is concerned, the important factors are the quality of materials used and the internal tolerances. Whether it is a short throw or a long throw shock is not directly related to shock life. In fact, the shorter the travel of the piston in the shock, the more force that needs to be generated per movement of the piston to provide a specified level of damping. As a result, the valves in the shock (assuming a fluid type shock) will undergo more stress & require tighter tolerances than a shock with a longer travel. As the parts wear, dimension changes will be more noticeable in a shock with a shorter travel compared to a longer travel. After about 23k miles, the front shocks in my 95 993 are worn. It is noticeable as a pogo stick effect on the freeway at speeds around 60-70 mph when traveling over uneven road. No leaks and the push down on the fender trick is not useful as the fender does not move when pressed on (without denting the fender). They will eventually be replaced with HDs.