*EDIT*
For people searching for a rough DIY of how to do this swap, here's a link to one of my later posts
http://forums.bimmerforums.com/forum...0&postcount=53
Ok, i've done some searching and I'm pretty sure I know everything that I need, but I wanted to confirm. To swap the M5 limited slip differential you need:
M5 LSD
Second half of the M5 drive shaft
EITHER: M5 half shafts
OR
e32 740i/e38 740iL/e31 850 diff side output flanges to use with the 540 axels.(P/N 33131214087) E32(#1)= http://realoem.com/bmw/showparts.do?...54&hg=33&fg=10
E38(#15)= http://realoem.com/bmw/showparts.do?...41&hg=33&fg=05
Questions:
1. If I swap the M5 half shafts, will my abs/ speed sensor still work?
2. I know the M5 half shafts are significantly thicker, but does the 540 run the chance of snapping the oe shafts with the LSD? Everyone says just swapping diff side output flanges and reusing the 540 shafts is significantly easier than swapping the M5 shafts in.
3. Do I need both diff to half shaft flanges AND half shaft to knuckle flanges, or do I just need the diff to shaft flanges?
4.Does the drive shaft need to be re-balanced if you only use the second half? Will the engine side of the shaft bolt straight up to a 540i manual tranny?
5. Do I need to replace the diff output seals if I swap the output flanges?
Basically, if I buy the whole M5 sub frame with axels/lsd, anda drive shaft, all I need to do is:
swap over some e38 740iL/850/e32 740i output flanges to the M5 diff,remove the 540 half shafts and place them in the M5 lsd, remove the 540 sub frame with drive shaft, install the M5 sub frame and put the M5 driveshaft in.
I'm sorry if this seems a bit long, but I want to make a conclusive thread over everything that is required to swap the M5 lsd into its baby brother.
Last edited by gotodefcon62; 03-22-2012 at 12:44 AM. Reason: Adding link to DIY post
aYou'll want to use the whole driveshaft because it is balanced as a unit.
Questions:
That's a lot more labor intesive than swapping the flanges. Not sure if it's worth the hassle.1. If I swap the M5 half shafts, will my abs/ speed sensor still work?
You are only increasing transmitted torque by about 10% I wouldn't worry about the axles snapping, correction am not. I'm just swapping the flanges on my m5 diff swap.2. I know the M5 half shafts are significantly thicker, but does the 540 run the chance of snapping the oe shafts with the LSD? Everyone says just swapping diff side output flanges and reusing the 540 shafts is significantly easier than swapping the M5 shafts in.
Just the flanges on the axle. you can use e31/e32/e38 shafts iirc. they might also be off of an e34 540i.3. Do I need both diff to half shaft flanges AND half shaft to knuckle flanges, or do I just need the diff to shaft flanges?
From what I've read yes it will be if you only use the second half. Better off using the whole thing.4.Does the drive shaft need to be re-balanced if you only use the second half? Will the engine side of the shaft bolt straight up to a 540i manual tranny?
Not usually. Most people have been fine just swapping the flanges.5. Do I need to replace the diff output seals if I swap the output flanges?
You're probably better off swapping the diff into your existing subframe and using your factory axles with out swapping the whole subframe. It will be less work that way i would assume. I'm just waiting on my driveshaft to swap mine in.Basically, if I buy the whole M5 sub frame with axels/lsd, anda drive shaft, all I need to do is:
swap over some e38 740iL/850/e32 740i output flanges to the M5 diff,remove the 540 half shafts and place them in the M5 lsd, remove the 540 sub frame with drive shaft, install the M5 sub frame and put the M5 driveshaft in.
I'm sorry if this seems a bit long, but I want to make a conclusive thread over everything that is required to swap the M5 lsd into its baby brother.
Last edited by peetiewonder; 01-05-2012 at 01:42 AM.
E34 525iT5
Ok that sounds good. I'm hoping I'll be able to get this done in the next couple of days, so we''ll see how it goes.
Good luck. I'm hoping to have my driveshaft by monday so I'll probably do the install on wednesday or thursday night.
E34 525iT5
If I remember correctly, the sensor ring is in the wheel bearing. Changing the axle shafts shouldn't make a difference.
Edited. Correction, the sensor ring is on the end of the axle shaft, but it should not make a difference in the wheel speed measurement.
Last edited by AvusRacer; 01-05-2012 at 09:16 AM.
Ok so you definitely need the e28 m5/e31/32/38 diff flange p/n 33131214087 to use the 540 half shafts with the M5 diff? ( http://realoem.com/bmw/partxref.do?part=33131214087 )
How would they drop out once The drive shafts fitted at both ends?
Would love to know if this defo worked for you guys please.
There is a lot of bad info in some of the above posts.
I've swapped a few M5 diffs using the M5 halfshafts and by replacing the M5 flanges so I could use the 540 halfshafts. The flanges are much easier to swap that pulling the halfshafts out. You don't want to use your 540 flanges in the M5 diff, they will pull out and because the C-clip lock ring will not snap into the M5 diff. The halfshafts have CV joints on each end which can move and pull the flange out. Oil can come out and dirt can get in, don't do it.
The wheel speed sensor is in the wheel bearing, doesn't matter what halfshaft you use the sensor won't be effected. Your cruise control will still work, but if you had a '99 and up 540 with the M62tu engine the cruise wouldn't work reliably.
You will not snap the 540 halfshaft, I'm using them with an M5 diff and have ~175 HP over stock and they are holding up fine.
You don't want to drop the subframe to do this, that's a lot of work that will take you MUCH longer.
Have you looked at the tools you will need? One of the nuts on the back side is difficult to get a wrench or socket on so make sure you can get a tool on it before you start.
The front of the M5 driveshaft will bolt right up to your tranny.
Thank you so much Jim, that's awesome. I picked up a pair of e38 740iL flanges the other day. I'm not gonna be able to do this swap any time soon though .
The only reason I'd want to drop the sub frame is because I bought the whole M5 sub frame with the diff attached. I could go ahead and change the bushings and everything( I know I need a BMW tool for that). One question I do have is does the 540 have body mounting brackets for the M5 cross braces? http://realoem.com/bmw/showparts.do?...79&hg=33&fg=30 (part 18 in the diagram). I'd love to use those braces.
Good thread, I'll have to keep this in mind.
e30 84 340i m6x powered.
e34 89 535i 5speed - current DD
e24 89 635csi - maybe a DD?
e34 93 525i (m50tu) - gone
e39 540i 6spd m-sport - gone
e53 x5 4.4l - gone
e30 89 325i (m20) - gone
Great thread, I now posess all the parts except the prop.
Soon I shall be able to ditch my welded diff.
I also bought the complete subframe with everything attached, I drove to Long Island to pick it up, had to take it all apart to get it to fit into the car.
Anyone need rear M5 calipers (Powder Coated black). Got the rotors and wheel carriers too. They are complete and come with almost new pads.
Sold the subframe a long time ago.
I looked at those #18 brackets but didn't really see where they could be attached to the body. Maybe some of the underbody plastic needs to be removed?? I'll look again when I have the car up on 4 jack stands for it's winter mods/maintenance.
Last edited by JimLev; 01-13-2012 at 01:30 PM.
Will the 540 input flange not swap onto the m5 diff to save using the m5 prop?
Ah thought that might be the answer
That's the idea man. I wanted to have a definitive thread on this diff swap.
The 540 flanges will swap, but the c-clip will not "clip" so you run the risk of getting nasty stuff into your diff while you drive from what I understand. It's much better to use either the m5 half shafts or use the e28/31/32/38 flange,but you have to make sure you get the right one. I got the wrong one myself...
Also, peetiewonder is right about the driveshaft. You can either use the whole M5 driveshaft, or just the second half of it, but then you have to get your hybrid 540/M5 driveshaft re-balanced. I may end up going this rout if it's cheap because I know my guibo has fewer miles on it than my donor car...
Sounds good man, I'd love to hear what you find. I don't expect our cars to have body side mounting points, but a man can dream can't he?
I've just ordered the right couplings in (I hope anyway from a 94 e34 540 diff) and I have a brand new oem guibo on my current prop which hasn't been rebalanced so whichever set of components I use I'll probably get it balanced again anyway.
They will fit fine in any non-M5 E39. They bolt underneath the crossmember that supports the exhaust just before the Y-resonator. If you search here you will find a post by a member who installed them in their 528i or 540i (can't quite remember which one specifically)
My car will be getting a pair.
2003 M5 LSx l 6 Spd Manual l 4.10 LSD
Build Thread
The chassis must always be regarded as a means to an end and never as an end itself
So that's where they bolt to. Never been under an M5.
IIRC I did see extra holes in the rear exhaust crossmember bracket.
Maybe that will reduce some of my wheel hop when I want to make the jump to lightspeed from a stop??
For $160 each maybe I'll try to find used ones or weld some parts together and make them myself.
Last edited by JimLev; 01-14-2012 at 01:41 PM.
Wheel hop is the same reason I'm looking to get these. I'm sure they will not completely cure it but will help. I'd be interested in hearing what your thoughts are on wheel hop in these cars and possible solutions.
Fabricating a pair of those braces should be relatively easy and cheap with regard to material cost.
2003 M5 LSx l 6 Spd Manual l 4.10 LSD
Build Thread
The chassis must always be regarded as a means to an end and never as an end itself
Great deal, guess I need to start looking there. For that price I'd rather have the real McCoy.
[QUOTE=Schitzo;23491768]Wheel hop is the same reason I'm looking to get these. I'm sure they will not completely cure it but will help. I'd be interested in hearing what your thoughts are on wheel hop in these cars and possible solutions.
QUOTE]
If I come out of the hole at anything above 1500 RPM and give it warp power the back suspension jumps so hard it hits the bumpstops. It won't stop until I back down the power.
It did it when it was new just the same as it does it now. Stiffer springs and some Koni FSD's reduced it just a little bit but not much.
Haven't had much time to look at it over the years, I just make sure to keep the RPM at 1500 when I launch.
Stiffer shocks shoud help but that would probably result in a stiff ride.
Adding the M5 diff didn't help much either.
Last edited by JimLev; 01-14-2012 at 02:08 PM. Reason: added M5 diff info
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