88 drive shaft compared to 89

[catchuk]

I have an 88 325is build date 8/87 and need a new driveshaft according to realoem the 6/88 and up driveshaft is 7 mm longer. has anyone tried using a late model one in their car? What did bmw do differently in the later cars to make the driveshaft longer the wheelbase is the same right? the differential is the same too I believe? anyone have any thoughts. did they feel like the shaft wasnt long enough and made it longer.

[Julien]

I know some 88 shafts have a vibration dampener in front of them... but it's not 7mm long

[catchuk]

i was thinking that may be the reason, I measured it and its 3mm. I dont run mine anyway that would be a 4mm diff now, did they stop putting th balancer on the late models?

[catchuk]

actually its only a 6mm difference, i just looked it up on realoem 1483mm compare to1489mm

[guibo09]

wont the difference be taken up at the center spline?

[catchuk]

wont the difference be taken up at the center spline?

I was thinking the same thing!

[Jon325i]

If there is a slight difference in length (3-7mm), the longitudinal movement permitted in the splines of the driveshaft will allow for this difference. Another thing to keep an eye out for is which center support bearing applies to your application. I know the drive shaft from the late 88 cars onward use a smaller diameter CSB than the earlier cars - one of the easiest ways it to measure the space of the holes on the mounting bracket (earlier cars are spaced farther apart). I learned this lesson a couple years ago when I needed to replace my driveshaft and picked up a '87 325is core for cheap from a friend only to find out it wouldn't fit correctly in my '91 325i. Be sure to double check the CSB part numbers to ensure you have the right one before you start getting your hands dirty.

Pictured below are the two I am referring to. The one on the left (with white stripe) is the early example while the one on the right is the late model.



Jon

[xLibelle]

thanks Jon

[catchuk]

Thanks John that was really helpful!

[catchuk]

can anyone measure the length between the holes for the late model and the early model?

[Maluco]

generial disgution?

[xLibelle]

Late model is 130mm for CSB mount width.

Had trouble finding thread - Mods, please move to Driveline forum?