Clear up transmission to driveshaft option

[nholm325e]

Hey guys, I know this has been gone over many many times but I have been doing alot of reading and seems i am getting mixed answers.
I have a 87 325e, will the e36 325 transmission bolt up correctly to my existing e30 325e drivshaft??

-Nick

[surebimmer]

edited

[FredK]

The E36 325 transmission still has a small 78 mm bolt circle diameter (BCD) output shaft. The 328/M3 has a 96 mm BCD output shaft.

The 325e had a 78 mm BCD driveshaft input flange up to 5/86. After 5/86 the BCD increased to 96 mm.

So Nick, check the production date on your 87 325e. It's on the doorjamb. Or, if you provide the last 7 digits of your VIN, it can easily be checked. If you have an early eta, you can reuse your driveshaft with the E36 325 transmission. If not, you'll have to source a different driveshaft or change the output flange of the transmission.

[nholm325e]

hey thanks for the help!

Its 11/86 so how would i go about changing the output flange on the e36 transmission, what would i need in order to do this??

[matt]

If not, you'll have to source a different driveshaft or change the output flange of the transmission.

I have never seen anyone who's done the swap output flanges thing.

There are some other considerations. The bolt circle diameters are the same, but the e30 guibo uses 10mm bolts and the e36 uses 12mm. Something needs to be done about this. I am running an e36 trans with an e30 driveshaft.

[FredK]

RobertK swapped output flanges on a ZF 320 to put into his 92 E36 325i. Granted, it's not the same exact thing, but it can be done.

Good point on the bolt diameters... I didn't know the E36 325i trans used 12mm guibo bolts! I guess you're going to have to use some kind of 12mm OD, 10mm ID bushings? I think ///Mpressive used an eta driveshaft with a ZF transmission. How'd you guys solve the 12/10mm bolt issue?

[e30polak]

i'm using an e36 m3 driveshaft on my s52 swap, with the '98 ZF 5spd. there is a myth that u need the e30 m3 driveshaft for it to work, but the e36 driveshaft will work fine. all u do is separate the two shafts and switch the center mounting bracket + ring from the e30 d-shaft into the e36 one. this will work fine, and will take a little bit of time and money off ur hands when looking for the e30 m3 shaft :pimp:

[matt]

i'm using an e36 m3 driveshaft on my s52 swap, with the '98 ZF 5spd. there is a myth that u need the e30 m3 driveshaft for it to work, but the e36 driveshaft will work fine. all u do is separate the two shafts and switch the center mounting bracket + ring from the e30 d-shaft into the e36 one. this will work fine, and will take a little bit of time and money off ur hands when looking for the e30 m3 shaft :pimp:

Not all e36 driveshafts will work, a lot of them won't. I don't know which are which aside from the fact that a lot of them have CV joints instead of rear u-joints, so those won't work.

Fred- I am using bushings as you described. I don't remember if it was an issue for Ben or not, he changed driveshafts about a million times chasing a vibration issue.

[surebimmer]

So it needs to be E36 1345mm verson with 3 bolts at the and 4 bolts non cv joint at the rear correct?

[FredK]

The 325, 328, and M3 driveshafts are closer to ~1500mm for the manual driveshafts. I haven't seen any CV style driveshafts on the 325 or 328. I've only seen it on the six bolt rear CV joint DS off a 1995 M3.

[e30polak]

sorry for any misinfo, my driveshaft is off a '98 m3 w/ ZF 5speed, so i know that that route works. however, i guess ur case is different

[surebimmer]

ya looks like the manual drive shaft on the e30 325i is just under 1500mm and the manual driveshaft from a e36 is 1512mm. So that how you can use the E36 drive shaft with the e30 center support bearing. Sorry for any misinfo.

[nholm325e]

OK i am kind of confused here..

If i go with the e36 transmission, your saying that with my post 5/86 ETA driveshaft that all i would need to do is change the ouput flange to the ZF 320 one?? They have different bolt diameter holes, what should i do??

-----Or should i just sell my ETA drivshaft and just get the e36 driveshaft?? Or will i run into more problems doing it this way??

[e30polak]

with the getrag u might need the e30 m3 d-shaft then, or u might need to shorten the shaft. but people r saying there is a different bolt pattern too, so i'm not exactly sure, sorry

[FredK]

If you choose to swap output flanges then you'll have to use 3 bushings to attach the eta driveshaft to the ZF320 flange, because the bolts will be undersized.

Matt, did you use off the shelf bushings, or did you machine some with a lathe? I'm thinking matching the thickness of the guibo would be preferable when it comes to pressing in a bushing...

Or, you could just use a E36 325 driveshaft! But you have to replace the center bearing support with one from an E30. I believe this will cause the center joint to operate at a slight angle, which may or may not affect driveshaft longevity. I've forgotten which type of swivel, u-joint or CV, allows for greater angle during operation.