M3 LSD in 135i

[vtl]

Originally Posted by flinchy

See if you can get ycw to add this driveshaft to their carbon lineup with that drawing? Would make these conversions a dream, albeit slightly more expensive

Good idea, would probably not be that big of an extra cost, I had to source the parts for the 330d propshaft, and get the propshaft customized on both ends. I got a quote from a big driveline shop for $500 just to customize the rear section (labour only) and balance it. Both ends customized i reckon would be close to 1k. The local place I took it to is a guy who operates out of his garage so it was cheaper, but he was highly recommended.

[vtl]

Originally Posted by Brule

I'm worried I'm going to snap an axle this year.
Is there a bolt on axle upgrade from an m3?

The m3 axles have thicker splines and different length than 135 335?

Or is it just a prick of a job pulling the hub off the axle?

The reason why I need bigger axles is that the output flanges on the M3 diff is a larger bolt circle. This means the CV joints are bigger than standard and the diameter of the driveshafts is thicker. The splines that go into the wheel hub's drive flange are the same.

It is a major headache to get the driveshafts out and in. You need to press out the old driveshafts with a special tool mounted on the drive flange. If its rusty and siezed the whole knuckle assembly needs to be removed and taken to a 50 ton press. Once you get the old ones out, you need yet another special tool to pull the new driveshaft in.

I just bought this recently to tackle the job of pulling the m3 shafts in:
http://www.ebay.com.au/itm/221720839...%3AMEBIDX%3AIT

I think the main weak point on a 135i/335i is the propshaft. On all 335is they have the inserted nut coupling which is a small CV joint, look up driveline failures and most of the pics are of that part failing. On my 135i I actually have a flex disc instead of an inserted nut coupling, but a lot of 135is also have the insert nut coupling. The problem is that upgrading the propshaft is going to be very difficult as the pinion on the diff would need to be changed to a stronger different flange. If you got a diff from a 135i with flex disc coupling (the 3 bolted flange) that would be a good candidate for an upgraded propshaft, but then you'd have to deal with getting an LSD fitted to the welded on ring gear. At this point you may as well throw on an M3 diff and driveshafts.

[DR-JEKL]

Good to see the ball rolling on this one again, thought you may change your mind by giving you a steer of a ///M equipped LSD 335i

[flinchy]

Originally Posted by vtl

Good idea, would probably not be that big of an extra cost, I had to source the parts for the 330d propshaft, and get the propshaft customized on both ends. I got a quote from a big driveline shop for $500 just to customize the rear section (labour only) and balance it. Both ends customized i reckon would be close to 1k. The local place I took it to is a guy who operates out of his garage so it was cheaper, but he was highly recommended.

Sorry I didn't read the whole thread (will tomorrow), buy why the 330d propshaft? The right length?

I thought most people got a V8 driveshaft and cannibalized the diff section of it and matched it up that way?

The carbon prop shafts, yeah, something like a bit over $1000 final retail?

Originally Posted by vtl

The reason why I need bigger axles is that the output flanges on the M3 diff is a larger bolt circle. This means the CV joints are bigger than standard and the diameter of the driveshafts is thicker. The splines that go into the wheel hub's drive flange are the same.

It is a major headache to get the driveshafts out and in. You need to press out the old driveshafts with a special tool mounted on the drive flange. If its rusty and siezed the whole knuckle assembly needs to be removed and taken to a 50 ton press. Once you get the old ones out, you need yet another special tool to pull the new driveshaft in. .

What's the trouble with getting the halfshafts in? The only ones I've had trouble with to date on the way out, are ones near an exhaust getting too much heat, and took a lot of sledge hammering, otherwise they slide in and out pretty easily. slide in especially with a push.

the hydraulic tool that gets screwed on is an absolute dream for stuck ones if you have it

I love seeing people do mods like this, might help one day if I ever do something similar at home

[vtl]

Originally Posted by flinchy

Sorry I didn't read the whole thread (will tomorrow), buy why the 330d propshaft? The right length?

I thought most people got a V8 driveshaft and cannibalized the diff section of it and matched it up that way?

The carbon prop shafts, yeah, something like a bit over $1000 final retail?



What's the trouble with getting the halfshafts in? The only ones I've had trouble with to date on the way out, are ones near an exhaust getting too much heat, and took a lot of sledge hammering, otherwise they slide in and out pretty easily. slide in especially with a push.

the hydraulic tool that gets screwed on is an absolute dream for stuck ones if you have it

I love seeing people do mods like this, might help one day if I ever do something similar at home

Got the 330d because it was the correct type and didn't want the car to be off the road. It sacrifices your original propshaft so if anything goes wrong you don't have a car to drive. I saw another guy doing the same 135i m3 diff swap and the propshaft builder put the m3 coupling on the wrong side.

Front section is around 90mm too long and will need to be shortened.

Have you tried getting e8x/9x driveshafts back in? I think in E46s and older they can be pushed back in by hand but e8x/9x its a very tight fit. You can hammer them in but that takes forever. I'll gladly pay for the tool to avoid that grief again. Even the ISTA service instructions tell you to use the special tool that attaches onto the driveshaft threads and pulls it into the hub flange.

[imske3000]

You're braver than most to take on a project like this. What do you think the end cost will be?

[vtl]

Originally Posted by imske3000

You're braver than most to take on a project like this. What do you think the end cost will be?

Bought the M3 diff, axles and propshaft for $2500, with all the stuff I had to buy and the custom prop the end cost will probably be around $3000-$3200.

[vtl]

Updated the drawing, I had measured from the edge of the diff flange, but the CV joint actually sits in a machined cutout. Propshaft is 4mm longer, resulting in 1325mm total, EXACTLY the same measurement as the dimension I calculated from realoem!

New PDF attached

[flinchy]

Originally Posted by vtl

Got the 330d because it was the correct type and didn't want the car to be off the road. It sacrifices your original propshaft so if anything goes wrong you don't have a car to drive. I saw another guy doing the same 135i m3 diff swap and the propshaft builder put the m3 coupling on the wrong side.

Front section is around 90mm too long and will need to be shortened.

Have you tried getting e8x/9x driveshafts back in? I think in E46s and older they can be pushed back in by hand but e8x/9x its a very tight fit. You can hammer them in but that takes forever. I'll gladly pay for the tool to avoid that grief again. Even the ISTA service instructions tell you to use the special tool that attaches onto the driveshaft threads and pulls it into the hub flange.

ahhh gotcha!

yeah, 2005 and 2006 models i've done, pushed in til the tip stuck out then spun the nut on, was either perfectly clean hubs or brand new though, which might explain it

[vtl]

Got the propshaft made up.

Unfortunately the donor M3 CV joint was damaged from the wrecked car. The CV cage was cracked and split in two

Thought about finding a 2nd hand V8 prop from a wrecked 5 or 7 series but decided I wanted the piece of mind with a brand new CV joint. Wasn't cheap, cost 300 for a new CV from FCP euro.

I used Jeff from Knox Driveshaft services and quite happy with the construction of the propshaft. A lot of propshafts I've seen have just been cut in the middle and butt welded up, resulting in a very weak propshaft. The welds are very neat and continuous and overall a very good job. The bonus is that he lives only a few streets away from me!

http://www.whereis.com/vic/ferntree-...lowId-12056837

Jeff took the time to machine out the OEM friction welded flanges on a lathe so they will slide into the propshaft tubing. This self aligns itself and is welded conventionally. This process also meant that we could not use the M3 propshaft tubing as it requires a bit more length since the flanges are now inside of the tubing. A matching length of pipe with the same bulked up middle section (instead of just a thin 60mm tube like the stock 335i/135i one) was used from a holden V8 propshaft and we have a nicely beefed up propshaft.

The new CV was greased and fitted, the propshaft was balanced and painted, ready to go on the car. Very reasonably priced too. Me very excite!

Some people have been having balance issues with M3 retrofit propshafts so fingers crossed no issues after the installation.

[Traf]

Wow nice schematics i love the paint job. As for the lenght, i found out that we got a lot of adjustability.
I wasnt supposed to use it but i ended up puting a N55 prop shaft, so it is 15mm longer than my original N54 shaft and was cut to 1339mm instead of 1325mm but still working fine.

It is most def not that big of a job as everybody thinks, more people should try it. Hardest part was getting the old axle shafts out...
No balance issue, the shaft was balanced by GKN and i used a black bolt on the blue mark of the input flange of the diff. So far so good and no vibrations.

As for the cost, if you're patient, it can be pretty cheap.
For me it was way cheaper than any other options.

Diff: 650€
Axles: 200€
E60 M5 prop shaft: 190€
N55 prop shaft (was intended for backup but i ended up using it): 200€
Cutting, welding and balancing: 160€
Bolts, reinforcing plates and stuff: ~50€

I paid way too much for the M5 shaft... But i would do it all over again.

Next step is to ditch the GKN viscolok and go for an upgraded e39 ZF diff.

[vtl]

After almost 2 years have finally got the LSD in.

Big thanks to Socket and titium for lending a hand.

The M3 diff, M3 axles and custom propshaft were swapped in. Also changed out the gear selector rod seal at the same time.

Result is no vibrations and a nicely locking LSD. Initially I test drove it with the e-diff and still felt like the rear brakes were still intervening a lot. I then coded it out and now the diff locks a lot more smoothly.

Very happy to have this installed and looking forward to doing some fun drives with it

[Traf]

Congrats man ! It is funny that i ended up finishing before you when i was the one asking questions not so long ago .

I should have swapped the selector rod too You went UUC DSSR ?

[vtl]

Originally Posted by Traf

Congrats man ! It is funny that i ended up finished before you when i was the one asking questions not so long ago .

I should have swapped the selector rod too You went UUC DSSR ?

Yeah definitely a project that requires continuous drive otherwise nothing gets done haha.

I swapped the selector rod for a new OEM unit thinking it was the source of my shifter play. It was not. I can tell you a uuc dssr will do nothing at all. Any improvement from installing a dssr would only be from the fact they come with new c clips. The c clips are the things that take up all the backlash. Also most of the play in the shifter is the foam piece in the gearshift rod joint. Replacing that, the c clips and shifter ball joint socket will give you a super tight gearshift.

[Traf]

Originally Posted by vtl

Yeah definitely a project that requires continuous drive otherwise nothing gets done haha.

I swapped the selector rod for a new OEM unit thinking it was the source of my shifter play. It was not. I can tell you a uuc dssr will do nothing at all. Any improvement from installing a dssr would only be from the fact they come with new c clips. The c clips are the things that take up all the backlash. Also most of the play in the shifter is the foam piece in the gearshift rod joint. Replacing that, the c clips and shifter ball joint socket will give you a super tight gearshift.

Then what is the solution to fixing our shitty shifts feel? Especially 1st and 2nd.

[vtl]

Originally Posted by Traf

Then what is the solution to fixing our shitty shifts feel? Especially 1st and 2nd.

If shift quality seems to be crap under power, try out some stiffer transmission mounts.

E46 M3 trans mounts - Reduce the movement enough that the shift never feels poor, no NVH penalty
UUC Black isolated mounts - Significantly stiffer than M3 mounts, shifts feel very solid. Bit more noise e.g road noise, drivetrain noise but still ok.

If shift quality seems to be crap in general, the rubber gasket that surrounds the gear lever and seals against the body might not be installed correctly and seated. If not seated correctly it can make the shifter feel stiff to go into certain gears

These carrier bushings (2 bushings) make a significant difference as well. When moving the shifter side to side, these bushings will make the side to side limits much more positive and solid.
2x http://store.uucmotorwerks.com/delri...--oval-p9.aspx

[sliderpass]

Looking good! I've still got my M3 DCT diff for sale if anyone is interested...

I'd be doing this if not for selling the car..

Nice work!

[sean5000]

Has anyone done this same swap but behind an n54 Auto? Looking for driveshaft lengths... Im doing it this weekend. I have a complete drop out from an E90 M3 that I found with solid subframe bushings, stainless lines, and upgraded diff bushings already installed!
I was hoping to just drop the car off at my driveline shop but they were leaning more towards just making a completely new driveline for $1,300 which Im not happy about. Im leaning towards having my Fabricator frankenstien my two driveshafts together first and seeing how that goes and my math isnt the greatest when I tried going off the lengths on the first page... any advice??

[vtl]

Don't bother trying to guess or calculate the lengths for anything other than a ball park figure. You will want to fit the subframe up and measure it

[sean5000]

Exactly the plan I just want to have some number in mind just as you did. No cutting or welding the driveline till the sub frame and diff are in the car and I can measure.

[vtl]

Auto gearbox is 2mm shorter so the propshaft is 2mm longer. My final propshaft was 1325mm so yours would be 1327mm

[sean5000]

In theory haha ok simple enough.. looking at it now I shouldn't be looking up info while I'm working as it looks plain as day to me now. Well thanks for the reply I'll add what I come up with and some pics wish me luck