Rear Axle Replacements

[206danebmx]

I am in the process of replacing my rear drive axles as the boots are starting to tear and the spline interface between the CV and axle is sloppy.

Does anyone have a good recommendation on where to source? I contacted the dealer and they are apparently no longer available (not to mention they were like $850/ea). The ones on ECS seem to have bad reviews (GSP brand).

Thoughts, experiences?

[ChuckDizzle]

I am in the process of replacing my rear drive axles as the boots are starting to tear and the spline interface between the CV and axle is sloppy.

Does anyone have a good recommendation on where to source? I contacted the dealer and they are apparently no longer available (not to mention they were like $850/ea). The ones on ECS seem to have bad reviews (GSP brand).

Thoughts, experiences?

Not sure if you have the time to wait, but you could have them rebuilt. I've had really good experiences with CV Axles Express, when I had to rebuild my E30 IX's axles. Sometimes, they will have a remanufactured pair ready to go and won't need yours as the core to build.

[blckstrm]

I found a set in a salvage yard.

Though at this point the rubber is old enough I'd probably think hard about redoing the boots before I put them back in the car.

[206danebmx]

Not sure if you have the time to wait, but you could have them rebuilt. I've had really good experiences with CV Axles Express, when I had to rebuild my E30 IX's axles. Sometimes, they will have a remanufactured pair ready to go and won't need yours as the core to build.

I just talked with CV axle express, but since I have worn splines it sounds like they are not easily rebuilt. I think I will just try the GSP ones as I can't find any other options.

[pbonsalb]

I have not read of a worn spline problem before but every year these axles get older. A few people have rebuilt them themselves. It is a pain but there is a thread on the job. I have read mixed reviews on the cheap auto parts store rebuilt or reproduction axles. I run Driveshaft Shop upgraded rebuilt axles but they now cost about $1200 for a set and you have to send yours in as a core. But they have not broken despite many dragstrip runs with 500-600 rwhp on drag radials. Broke drive shafts, clutches, differential output stubs and ZF320 transmissions.

[tjm3]

The GSP axles are really not that bad. For the M3, their axles are solid and not hollow like the stock units. I've only had a couple of issues with GSP and I've installed them in a bunch of different cars, including my Dinan 3 325i. I had one locked up right out of the box and one that made clicking noises also out of the box. The one that locked didn't have the restrictive metal collar under the boot which allowed the joint to move too much probably during shipping so something in there got cockeyed and un-recoverable. The set in my 325i have been in there for at least a couple of years with no problems. I was buying these things for about $75 per complete axle. GSP uses the cut off spline portions of used axles and then friction welds a new outer CV and also replaces the inners with new units. From what I can see, these are NOT German quality joints.

You can source the new, high quality CV joints from GKN, though. The inner is easy to find by diameter, bolt pattern and spline size but you'll need to be dedicated to replace outers. Cut and separate the spine portion from the CV joint, machine it and have the new joint welded back in. The originals are friction welded but I was tempted to try a standard weld. Never got around to it. The inner can also be sourced from GKN. There's several detailed axle 'reconditioning' threads in here, including mine, found with a good search.

Here's mine, but there are a couple of other good threads: https://www.bimmerforums.com/forum/s...light=cv+joint

If nothing else, these GKN links have some good info.

https://www.gknautomotive.com/en/Aftermarket/

https://www.gknautomotive.com/global...---english.pdf

[jaysonx]

I rebuilt mine, per a BMW Tech friend of mine, our axles are pretty foolproof as long as they are not abused. Wasn't that bad just be sure to correctly reassemble. There are more than a few HOWTO's on the topic. Also, not expensive to do.

[206danebmx]

Thanks for all the feedback guys.

My outer CV spline has a fair bit of slop between it and the axle, maybe 1/32" at the CV diameter. Normally I would probably just replace my boots and put the old one back on but I have also had some odd drivetrain slop feelings when shifting so would like to eliminate that as a possible cause.

Hopefully the gsp ones will be tighter.

[206danebmx]

Received my gsp axle, has the same slop as my OEM ones, maybe I'm overreacting but I would imagine there should've been no slop in the spline interface from the factory. I guess I'll replace the boots on my OEM ones and reinstall them, and ship back the gsp one.

[pbonsalb]

Is it possible you are confusing spline play with normal differential or cv joint play? The splines really don’t allow play.

[aeronaut]

Is it possible you are confusing spline play with normal differential or cv joint play? The splines really don’t allow play.

Yea, agreed. If there's any, any, play in the splines, something's wrong.

[206danebmx]

Its definitely the spline interface on my OEM shafts as I ripped off the old rubber boots and confirmed it, seems there is almost zero play in the CV balls. The new gsp one is hard to know for sure as I don't want to take the rubber off, probably gonna return it anyways.

[aeronaut]

If there is noticeable play in the spline, with new splines, then the hubs likely need replacing.

[pbonsalb]

You could buy a used set of M3 axles and rebuild them. 96-99 fit the 95. Or you could disassemble yours and try to figure out what is wrong. If it is the CV, maybe you can find a new CV joint. If the shaft itself is damaged then you will have to source a shaft. I know people have taken them apart and installed new CV joints though some just clean and regrease. I watched a friend rebuild one. Very messy job and getting the balls back in took some practice. I bought DSS, but they need good cores. I think it is the outer part that goes in the axle they need to reuse from the core.

[m3bs]

I just tried to install a set of replacement axles in my 95 M3. They came out of a ‘96 M3 (hollow shaft) and had been recently rebuilt. My hubs were recently replaced and are like new. I spent 4-5 hours fighting them and gave up. I cleaned and polished the splines with solvents, sandpaper, files, and even a Dremel tool, and still couldn’t get them to go all the way in. The old ones slipped back in with no problem. Suggestions on how to get the splines reworked?

[tjm3]

Side by side pics needed.

[pbonsalb]

I have struggled to get axles in before. And filed and brushed and cleaned splines and still struggled. There are axle installer tools. Basically a skinny sleeve you thread on to help you pull it through. I bought a kit but have not used it yet.

[m3bs]

Did you find a tool for the 27mm M3 thread? I haven’t seen one.

[pbonsalb]

Yes, M27x1.5. Should be able to see it in this picture if you can enlarge it enough.

D44B25A5-C068-4CC3-BF10-C032D3932918.jpg

Did you find a tool for the 27mm M3 thread? I haven’t seen one.

[aeronaut]

I have struggled to get axles in before. And filed and brushed and cleaned splines and still struggled. There are axle installer tools. Basically a skinny sleeve you thread on to help you pull it through. I bought a kit but have not used it yet.

I also recall them being a PITA. A few hours of WTF, then suddenly boom (after brushing and cleaning and etc.)
I think I used a small angle file to carefully clean each inside corner.