Did a s52 swap last year, and recently I've had a vibration only in second gear under WOT (wide open throttle). In any other gear it was not present. So, I decided to check out my driveshaft components and found out that my CSB had ripped from the bracket (bottom half only) and the u-joints were binding. So, I bought a m3 driveshaft (off a late 97 boston green e36 m3) with very good U-joints with no binding/play/awkward resistances in any direction/way, had it balanced and installed with a new CSB.
I will put all details below to help diagnose my problem.
10 months ago:
- 1987 325e Front half driveshaft mated with 1990 325i rear half driveshaft (binding u-joints)
- New Center Support Bearing
- New Large Guibo (96mm w/ 12mm bolts)
- ZF tranny with 2.93 lsd (off a 1986 325es)
Results - No vibration even at 160+mph till u-joints went bad 9 months later (rear half u-joints were bad resulting in noise when making a u-turn or sharp turns). Second gear WOT vibration.
Today:
- 1998 m3 Driveshaft (Very good u-joints)
- m3 driveshaft Balanced at Wenco Industries (Driveshaft Specialist of Hot Rods and Dragster Funny Cars) and inspected and was in very good condition by Mike (owner/manager).
- Bought another New Center Support Bearing
- Kept guibo as it was still good with no rips/stress wear
Results - Vibration on WOT in Second, Third, and Fourth. Vibration decreases in WOT when a higher gear is engaged.
Questions:
1) - What could possibly be the problem?
2) - I did everything right the second time as obviously the first try did not work out according to my plan, so why would it be worse than the intial problem itself?
3) - I adjusted the engine/tranny to the differential to get it as straight as possible, but did not use the special tools as they cost an ass load of money to purchase, could this be another possibility?
4) - I've read that the angle of the motor should be measured negative 3 degrees and the differential to be measured positive 3 degrees, so when under WOT (full load) they are straight. Another possibility?
Suggestions/Critism welcomed. I'd really like to figure this out as I've wasted my time/efforts to only worsen my problem.
I will put all details below to help diagnose my problem.
10 months ago:
- 1987 325e Front half driveshaft mated with 1990 325i rear half driveshaft (binding u-joints)
- New Center Support Bearing
- New Large Guibo (96mm w/ 12mm bolts)
- ZF tranny with 2.93 lsd (off a 1986 325es)
Results - No vibration even at 160+mph till u-joints went bad 9 months later (rear half u-joints were bad resulting in noise when making a u-turn or sharp turns). Second gear WOT vibration.
Today:
- 1998 m3 Driveshaft (Very good u-joints)
- m3 driveshaft Balanced at Wenco Industries (Driveshaft Specialist of Hot Rods and Dragster Funny Cars) and inspected and was in very good condition by Mike (owner/manager).
- Bought another New Center Support Bearing
- Kept guibo as it was still good with no rips/stress wear
Results - Vibration on WOT in Second, Third, and Fourth. Vibration decreases in WOT when a higher gear is engaged.
Questions:
1) - What could possibly be the problem?
2) - I did everything right the second time as obviously the first try did not work out according to my plan, so why would it be worse than the intial problem itself?
3) - I adjusted the engine/tranny to the differential to get it as straight as possible, but did not use the special tools as they cost an ass load of money to purchase, could this be another possibility?
4) - I've read that the angle of the motor should be measured negative 3 degrees and the differential to be measured positive 3 degrees, so when under WOT (full load) they are straight. Another possibility?
Suggestions/Critism welcomed. I'd really like to figure this out as I've wasted my time/efforts to only worsen my problem.
