a newbie question here....

i've been chasing a vibration that seems to be getting worse and suspect it may be the driveshaft since i'm still using my stock one with 157K miles on it and am now running an LE2 setup with close to 400RWHP. now granted, i've never run it on the track and haven't really ever had sticky tires on it to stress it too much. if this is my problem, what generally happens to a stock driveshaft as it begins to deteriorate...does it "twist"? i'm wondering if this could be my worsening vibration.

thanks

robert

 

At what driveshaft RPM does it start to vibrate? Have the u-joints ever been replaced?

 

Not sure about driveshaft RPM. i get the vibration at various speeds and seems to usually be near the bottom of a gear (i have an auto) when the car isn't making much torque and trying to pull. im not even sure there is a direct correlation to that scenario.

i had my stock shaft balanced at a local shop a while back but am not sure i trust the results. i dont know what rpm he balanced it to and he made the comment when i picked it up "that's probably about as good as we'll be able to get it". i've ruled out a number of things to date and am thinking it's either the driveshaft or bad engine balance at the machine shop...or maybe a little of both.

i know this isn't much info to go on and a little confusing info at that. mainly i just wanted to understand what generally happens to a driveshaft that is causing a vibration...whether they usually twist under the strain b/c of age and/or increased hp levels.