E21 Differentials and Driveshafts (The weak Point?)

For all your questions, problems and DIY stories
User avatar
Duracel79
E21 VIP
E21 VIP
Posts: 802
Joined: Thu May 29, 2008 6:54 pm
Location: Stevenage, Hertfordshire

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by Duracel79 »

Looks like we've had the first pictures of a broken differential (the LSD parts anyway). Went whilst Problemchild was on a trackday with an M52 doing the damage.

I'm guessing with the M50 inlet it was pushing about 220bhp and 210lbft, obviously I don't know if there was a remap involved or other spec, so may be off the mark here.

Hopefully Problemchild will post his pics up here as well with some more details :thumbsup

Regards

Ben


1982 323i (S54 "Test Mule" - to be rebuilt into M20 powered track car)
1983 316 (Taiga Thunder - The refined S54 Race car)
1982 635csiA (New project)
1985 728iA (For Sale)
2004 330d Touring (The Daily Hack / Tow Car / Load lugger)
problemchild75
E21 Fanatic
Posts: 377
Joined: Fri Jan 27, 2012 2:47 pm
Location: manchester
Contact:

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by problemchild75 »

m52, remap m50 inlet so probably a smidge over 200bhp. 3.9 e21 lsd with fresh oil and vey quiet. 6 fast but not hard ie not snatching gears and using lots of engine breaking shakedown laps of Anglesey circuit ended in the following pics. the 168mm is not up to the job IMO some say its the oil getting to hot that's the problem but after six sensible laps I doubt it. E12 lsd conversion underway.

Image
Image
Image
Image
Image
Image
Image

Image
Image
Image
Image
User avatar
croma_man
E21 Pro
Posts: 594
Joined: Fri Sep 07, 2012 1:18 pm
My E21(s): '83 EU 327i
Location: Slovenia (EU)
Contact:

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by croma_man »

ouch !

so a tuned M20 stroker is over the limit ?
User avatar
Jeroen
Site Admin
Posts: 29198
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by Jeroen »

I am wondering what happened because I've seen enough E21 diffs take over 200 BHP. Bearing that broke into pieces and ruined the rest on its way?
Regards/groeten, Jeroen
problemchild75
E21 Fanatic
Posts: 377
Joined: Fri Jan 27, 2012 2:47 pm
Location: manchester
Contact:

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by problemchild75 »

The bearings are all still ok. Somthing has given up and wiped everything else out though. I think it was one ot the side gears but that's just a best guess. I'm happy to test another if anyone wants to sponser the diffs :-D
User avatar
croma_man
E21 Pro
Posts: 594
Joined: Fri Sep 07, 2012 1:18 pm
My E21(s): '83 EU 327i
Location: Slovenia (EU)
Contact:

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by croma_man »

so next stop is a E12 sideloader?

you made me a very worried owner of a small diff :sealed
problemchild75
E21 Fanatic
Posts: 377
Joined: Fri Jan 27, 2012 2:47 pm
Location: manchester
Contact:

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by problemchild75 »

Yes side loader on way. Don't worry about your diff I might have been unlucky. But if your going to drive it hard a side loader might be worth thinking about whilst you still have a expensive small diff to sell.
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: E21 Differentials and Driveshafts (The weak Point?)

Post by J.K.jr.bad. »

Probably that diff simply was too old to keep that tension. We all get old and then we die. :innocent
-----------------
J.K.jr.bad.
M15KYY
E21 Fanatic
Posts: 280
Joined: Sun Jun 24, 2007 1:16 pm
Location: west midlands

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by M15KYY »

i had an e12 diff in the back of my m60 v8 e21 and didnt have any problems with the diff. the driveshafts however..... 7 destroyed in 6 months, inner joints every time apart from one.... complete waste of time. the only good thing to come of this was it stopped the underside of the car from rusting when it threw cv grease everywhere. i have now fitted an e36 m3 evo rear axle but as i can appreciate not everyone can/ wants to do this to their e21. i think the best solution would be to get a medium case diff from an e36 6 cylinder grafted onto either an e21/e30 rear axle with some half decent custom shafts. you'd never have to worry about it ever again. i have another e21 shell coming soon so i might look into creating a "bullet proof" bolt on e21 rear axle solution for those who want to chase big power. if i do i will make a jig and offer this on the the forum providing i have enough interest.
E21 316 M60
User avatar
Duracel79
E21 VIP
E21 VIP
Posts: 802
Joined: Thu May 29, 2008 6:54 pm
Location: Stevenage, Hertfordshire

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by Duracel79 »

M15KYY wrote:i had an e12 diff in the back of my m60 v8 e21 and didnt have any problems with the diff. the driveshafts however..... 7 destroyed in 6 months, inner joints every time apart from one.... complete waste of time. the only good thing to come of this was it stopped the underside of the car from rusting when it threw cv grease everywhere. i have now fitted an e36 m3 evo rear axle but as i can appreciate not everyone can/ wants to do this to their e21. i think the best solution would be to get a medium case diff from an e36 6 cylinder grafted onto either an e21/e30 rear axle with some half decent custom shafts. you'd never have to worry about it ever again. i have another e21 shell coming soon so i might look into creating a "bullet proof" bolt on e21 rear axle solution for those who want to chase big power. if i do i will make a jig and offer this on the the forum providing i have enough interest.
E12 diff with custom shafts and GKN Motorsport joints on my car. No issues so far with over 330bhp. But not a cheap solution (doubt there is a cheap solution).

Ben
1982 323i (S54 "Test Mule" - to be rebuilt into M20 powered track car)
1983 316 (Taiga Thunder - The refined S54 Race car)
1982 635csiA (New project)
1985 728iA (For Sale)
2004 330d Touring (The Daily Hack / Tow Car / Load lugger)
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: E21 Differentials and Driveshafts (The weak Point?)

Post by e21-Mark »

Duracel79 wrote:
M15KYY wrote:i had an e12 diff in the back of my m60 v8 e21 and didnt have any problems with the diff. the driveshafts however..... 7 destroyed in 6 months, inner joints every time apart from one.... complete waste of time. the only good thing to come of this was it stopped the underside of the car from rusting when it threw cv grease everywhere. i have now fitted an e36 m3 evo rear axle but as i can appreciate not everyone can/ wants to do this to their e21. i think the best solution would be to get a medium case diff from an e36 6 cylinder grafted onto either an e21/e30 rear axle with some half decent custom shafts. you'd never have to worry about it ever again. i have another e21 shell coming soon so i might look into creating a "bullet proof" bolt on e21 rear axle solution for those who want to chase big power. if i do i will make a jig and offer this on the the forum providing i have enough interest.
E12 diff with custom shafts and GKN Motorsport joints on my car. No issues so far with over 330bhp. But not a cheap solution (doubt there is a cheap solution).

Ben
What is a ballpark figure on the custom shafts & GKN joints, for those folk with sideloaders fitted?
User avatar
Duracel79
E21 VIP
E21 VIP
Posts: 802
Joined: Thu May 29, 2008 6:54 pm
Location: Stevenage, Hertfordshire

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by Duracel79 »

£270 + VAT - Custom Shafts the correct length each (F1 grade material)
£168.67 + VAT - GKN Motorsport CV's each
£103.22 incl VAT - GKN Fast boots set of 4
Plus delivery from 3 suppliers

I don't really want to add it up, its a bit scary :screwy

Not sure how that compares to the costs of an M3 rear end like M15KYY's

Ben
1982 323i (S54 "Test Mule" - to be rebuilt into M20 powered track car)
1983 316 (Taiga Thunder - The refined S54 Race car)
1982 635csiA (New project)
1985 728iA (For Sale)
2004 330d Touring (The Daily Hack / Tow Car / Load lugger)
User avatar
nas80
E21 Mad
Posts: 2975
Joined: Sun Jun 14, 2009 12:12 am
Location: West Yorkshire

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by nas80 »

Those prices are for 2x or are they EACH.
[img]http://s13.photobucket.com/albums/a285/nasbucket/forumsig.jpg[/img]
User avatar
Duracel79
E21 VIP
E21 VIP
Posts: 802
Joined: Thu May 29, 2008 6:54 pm
Location: Stevenage, Hertfordshire

Re: E21 Differentials and Driveshafts (The weak Point?)

Post by Duracel79 »

shafts and CV's are each, only the boots is for the set.
1982 323i (S54 "Test Mule" - to be rebuilt into M20 powered track car)
1983 316 (Taiga Thunder - The refined S54 Race car)
1982 635csiA (New project)
1985 728iA (For Sale)
2004 330d Touring (The Daily Hack / Tow Car / Load lugger)
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: E21 Differentials and Driveshafts (The weak Point?)

Post by e21-Mark »

:shock
Post Reply