How to tell if struts/shocks are bad with very stiff springs

[MustangLife]

Hey all. I was wondering how to really tell if the struts or shocks need replacing when a car has bery stiff springs. I know people will chime in and say push up and down on the car and count how many times it bounces back and forth. But with springs like Eibach Sportlines, etc. The car isn't gonna move much with new or bad struts/shocks. Is pulling 1 of the struts and 1 of the shocks really the only sure way?

Thanks
Josh

 

[san~man]

You'll have a hard time pushing down on a fender to check for a blown unit, especially if the spring rate is high.

You should be able to notice that, while driving, the side with the questionable unit will "float" and seem to "bob" up and down (sort of like a boat on the water). When my Bilstein was blown, it was easy to tell as the handling was noticeably "off" and different, and I experienced those symptoms.

 

[trombonedemon]

Also, check your tires for uneven wear. I'm saying this b/c my front shocks wear still the stockers after about 111 thousand miles, and the tires start to wear unevenly like the tire was taking the extent of the road force.
Once the front shocks were replace the tire started wear evenly again.
Once you replaced the front struts, woud be a good idea to get the steering rack bushings replaced.

 

[flstang65]

You can also look for fluid leaking from the shocks/struts.

 

[san~man]

You can also look for fluid leaking from the shocks/struts.

Good point, but my Bilstein didn't show any signs of leaking fluid. Most likely the internals failed.

The only SURE way is to remove it and compress the shaft. You'll know for sure then.