168mm e36 lsd into e21 case?

For all your questions, problems and DIY stories
User avatar
joey79
Newbee
Posts: 7
Joined: Mon Jun 29, 2009 8:16 am

168mm e36 lsd into e21 case?

Post by joey79 »

I picked up a 3.45 lsd from an e36 318i today at pick and pull for $75. I'm wondering if it's possible to swap the lsd internals into my e21 diff case. They're both 168mm diffs so I'm guessing it would work, but I couldn't find any positive confirmation by searching. Has anyone tried this?


Image
User avatar
e21-Mark
E21 Master
Posts: 5715
Joined: Fri Mar 21, 2008 2:19 pm
My E21(s): 316 m52/2.8 Cat Cams & Jenvey ITB
Facebook page: https://www.facebook.com/JackyardBackoff
Location: Cornwall - UK

Re: 168mm e36 lsd into e21 case?

Post by e21-Mark »

Let us know how you get on? I think Jason323 has swapped some diff internals, or at least knows a bit more on the subject? You could ask on e21 Legion too?
User avatar
Duracel79
E21 VIP
E21 VIP
Posts: 810
Joined: Thu May 29, 2008 6:54 pm
Location: Stevenage, Hertfordshire

Re: 168mm e36 lsd into e21 case?

Post by Duracel79 »

Should be able to do it. Use the E21 casing, crown wheel and pinoin parts. just fit the E21 crownwheel to the LSD and fit into the E21 case. Would be worth checking the clearances once built up using some engineers blue.

Ben
1982 323i ("Test Mule" - to become an M20 powered track car)
1983 316 (Taiga Thunder - S54 Track car)
1982 635csiA (Another Weldathon)
2004 330d Touring (The Daily Hack / Tow Car / Load lugger)
1974 3.0 csi (The first Weldathon)
Markw
E21 starter
Posts: 38
Joined: Fri Feb 27, 2009 12:37 pm
Location: Sussex

Re: 168mm e36 lsd into e21 case?

Post by Markw »

I've been trying to do this too. Crownwheel fits the LSD and it has the same overall dimensions as the free diff that came out, but I can't get the assy to enter the case. Any tips from anyone??

Mark
User avatar
joey79
Newbee
Posts: 7
Joined: Mon Jun 29, 2009 8:16 am

Re: 168mm e36 lsd into e21 case?

Post by joey79 »

What exacly is preventing it from entering the case? How tight is the clearance?
Image
User avatar
joey79
Newbee
Posts: 7
Joined: Mon Jun 29, 2009 8:16 am

Re: 168mm e36 lsd into e21 case?

Post by joey79 »

Any other suggestions?
Image
User avatar
Duracel79
E21 VIP
E21 VIP
Posts: 810
Joined: Thu May 29, 2008 6:54 pm
Location: Stevenage, Hertfordshire

Re: 168mm e36 lsd into e21 case?

Post by Duracel79 »

Markw wrote:I've been trying to do this too. Crownwheel fits the LSD and it has the same overall dimensions as the free diff that came out, but I can't get the assy to enter the case. Any tips from anyone??

Mark
I remember mine being tight to get through the opening. Lots of wriggling and cursing but eventually it went in. Removing the bearings should help then press them back on throught the driveshaft holes?

Ben
1982 323i ("Test Mule" - to become an M20 powered track car)
1983 316 (Taiga Thunder - S54 Track car)
1982 635csiA (Another Weldathon)
2004 330d Touring (The Daily Hack / Tow Car / Load lugger)
1974 3.0 csi (The first Weldathon)
User avatar
nas80
E21 Mad
Posts: 2975
Joined: Sun Jun 14, 2009 12:12 am
Location: West Yorkshire

Re: 168mm e36 lsd into e21 case?

Post by nas80 »

whats the maximim torque rating of the e36 diff? is it more than the e21 or the same?
[img]http://s13.photobucket.com/albums/a285/nasbucket/forumsig.jpg[/img]
User avatar
e21-Mark
E21 Master
Posts: 5715
Joined: Fri Mar 21, 2008 2:19 pm
My E21(s): 316 m52/2.8 Cat Cams & Jenvey ITB
Facebook page: https://www.facebook.com/JackyardBackoff
Location: Cornwall - UK

Re: 168mm e36 lsd into e21 case?

Post by e21-Mark »

240/250 ft/lbs iirc. I might be wrong tho - and often am. ;)
User avatar
e21-Mark
E21 Master
Posts: 5715
Joined: Fri Mar 21, 2008 2:19 pm
My E21(s): 316 m52/2.8 Cat Cams & Jenvey ITB
Facebook page: https://www.facebook.com/JackyardBackoff
Location: Cornwall - UK

Re: 168mm e36 lsd into e21 case?

Post by e21-Mark »

Duracel79 wrote: I remember mine being tight to get through the opening. Lots of wriggling and cursing but eventually it went in.
nudge nudge, wink wink, say no more.
Markw
E21 starter
Posts: 38
Joined: Fri Feb 27, 2009 12:37 pm
Location: Sussex

Re: 168mm e36 lsd into e21 case?

Post by Markw »

Duracel79 wrote:
Markw wrote:I've been trying to do this too. Crownwheel fits the LSD and it has the same overall dimensions as the free diff that came out, but I can't get the assy to enter the case. Any tips from anyone??

Mark
I remember mine being tight to get through the opening. Lots of wriggling and cursing but eventually it went in. Removing the bearings should help then press them back on throught the driveshaft holes?

Ben
It fits OK with the bearings removed, but I had to destroy them to get them off. Made a simple job VERY expensive. Also the manual recommends initial setting up without the pinion to get the bearing preload right. Pinion won't come off with diff in situ. Back to square one!

Looks like I'll have to set it up "by eye" like in the old days. It'll either clonk or whine. Ho hum......

Mark
User avatar
J.K.jr.bad.
Upcoming E21 fanatic
Posts: 100
Joined: Thu Jan 17, 2008 10:09 am
My E21(s): BMW 315, BMW 323
Facebook page: http://www.facebook.com/ADParts
Location: Latvia
Contact:

Re: 168mm e36 lsd into e21 case?

Post by J.K.jr.bad. »

Remove lid with bearing on. Put in LSD element and screw that lid back on. That how I did. Otherwise everything works just fine.
-----------------
J.K.jr.bad.
User avatar
joey79
Newbee
Posts: 7
Joined: Mon Jun 29, 2009 8:16 am

Re: 168mm e36 lsd into e21 case?

Post by joey79 »

Image
User avatar
quinn_656
Upcoming E21 fanatic
Posts: 179
Joined: Fri Jan 19, 2007 5:20 pm
Location: N.Ireland
Contact:

Re: 168mm e36 lsd into e21 case?

Post by quinn_656 »

i just ginded a litte bit away from the sides of the casing to let it rotate into place used the 3.91 ratio crown wheel and pinion matched the correct bearing races. i used one of the e36(2.0mm) shims on the left(crown wheel) side, had to drill a few more holes and an e21 (1.7mm) shim in the right hand side im no expert but the back lash seems ok the unit is tight within the bearings the gears are meshing with a very small amount of backlash is you can just about feel the movement and the diff is still dry (no LSD oil yet) i replaced all the seals my local hydraulic man got them for me very reasonable
My build
http://www.bmwe21.net/forum/viewtopic.php?f=7&t=12052&start=0

www.quinnpiling.com
User avatar
murran
E21 Pro
Posts: 1309
Joined: Fri Nov 09, 2007 9:20 pm
Location: sheffield

Re: 168mm e36 lsd into e21 case?

Post by murran »

all this trouble and effort, and for what? just weld up an open diff. its a compromise yes, but the shortcomings are few.
try it! personally i still smile when i have to turn a tight corner sencibily. but then i can step it out on a roundabout safe in the knowledge i have complete predictability on what the cars going to do.

you do your first doughnut........ you'll never go back to an lsd with 25% lock up.

plus welding it is free!
Image
Jeroen wrote:Bmwe21.net, for all your insurance solutions :P
Post Reply