Vibration after 5spd swap

[Marcus33]

So i completed my 5spd swap a few weeks ago.

Replaced centre bearing, and i removed that vibration dampener

Im experiencing a slight vibration in first gear around 1400-2100rpms.

If i really step on it from launch, that vibration becomes pretty loud. But besides that all is smooth.

the vibration is also there around the same RPMs in 2nd gear, but not 3rd etc.


Im guessing its torque on the drive shaft? Any ideas on what i should try to do to rectify this? Is it because i removed that vibration dampener? or possible subframe bushings etc?

[ForcedFirebird]

Sounds like the drive shaft is out of phase, or a u-joint is bad. The two halves of the drive shaft can only go on two directions to maintain balance - I have swapped halves dozens of times with no ill effect. The u-joints have to line up like the pic on realoem...

http://www.realoem.com/bmw/enUS/partgrp?id=1113-USA-02-1991-E30-BMW-325i&mg=26

Note the orientation of the joints in the pic. They can be 180 degrees out, but 90 degrees they vibrate.

Just a hunch, though, tough to diagnose through text.

[TobyB]

Or something is hitting. In 1st and 2nd, the motor and trans move more than they
do in higher gears due to torque.

Look around underneath for shiny spots...

t

[ForcedFirebird]

^^simple test. Open the hood and put the car in gear with clutch in and e-brake on (or wheel chalk). Slowly release the clutch and take note of engine movement. Easy to do in an e30 with the reverse hood :)

[Marcus33]

thanks guys, im going to mess around with it, and see what i can figure out, i had separated the driveshaft to do the Center bearing. I know i aligned the markings on the two pieces, but i never checked the actual alignment of the ujoints

[ForcedFirebird]

The marks are only there for a guide and can easily be a spline tooth or two off.