How do I remove diff rear crossmember?

[BMW2JZ]

Hi Guys,

I'm not very versed in panel work and am currently trying to remove the diff rear subframe crossmember from the vehicle as the large case diff is hitting it and I need to install a new one further back to give room for the sway bar and also new dual rear diff mounts.

I have exposed the tabs on the part but I cannot see any evidence of spot welds?

Is this part spot welded along all flanges or only the ends and some adhesive to hold it to the boot floor?

You can see the tabs I've traced in red.



Thinking I'll use some 50x35mm RHS to fit the new one and just extend a 'tab' each end to lap over the underside of the chassis rails. Will probably tie it back into the cage in the boot also.

Thanks in advance.
Ben

[JGood]

You may need to use a wire wheel to get that thick primer off of there to see the spot welds. When I replaced some sheet metal on my car I found that I couldn't see the spot welds until I got down to bare metal, as they don't really bulge out or anything.

[BMW2JZ]

Thanks JGood, I stumbled on a photo in someones build thread on here today that clearly shows the spots from inside hte boot, so they must be there.

I got hold of a spot weld drill today and will have a crack tonight.

[JGood]

Thanks JGood, I stumbled on a photo in someones build thread on here today that clearly shows the spots from inside hte boot, so they must be there.

I got hold of a spot weld drill today and will have a crack tonight.

I went through 2 of those (4 tips total) doing my front wheel housing and core support. My advice: Use a punch to get a nice solid dimple, or that thing is gonna jump around like crazy. Go slow, with light pressure.

[BMW2JZ]

I went through 2 of those (4 tips total) doing my front wheel housing and core support. My advice: Use a punch to get a nice solid dimple, or that thing is gonna jump around like crazy. Go slow, with light pressure.

Thanks for the advice mate. The fella at the tool shop reckoned he did about 200 welds with the exact tool I have, so touch wood I can get through this from it at least..

[BMW2JZ]

Not at all pretty, but it's out and gone. I will be replacing some of the boot floor panel and will cut out the bars from the offset diff mount to cage and replace it with two new bars back to the cage from the new RHS crossmember.

[Wanganstyle]

E32 210mm v12 diff rear plate fits much better than E28M5 diff rear plate mount!

If you are looking for a front 4 bolt flange (to run a modified e30 driveshaft) then you can fit the E28M5 front flange on.
4 bolt original 188mm flange from e30 (cast fingers) has been proven here in the west coast usa to 1,000rwhp and 30++ 1/4 mile passes without issues.

I Have set these up before (210mm LSD unit with 4 bolt for drag racing)

[BMW2JZ]

E32 210mm v12 diff rear plate fits much better than E28M5 diff rear plate mount!

If you are looking for a front 4 bolt flange (to run a modified e30 driveshaft) then you can fit the E28M5 front flange on.
4 bolt original 188mm flange from e30 (cast fingers) has been proven here in the west coast usa to 1,000rwhp and 30++ 1/4 mile passes without issues.

I Have set these up before (210mm LSD unit with 4 bolt for drag racing)

Thanks for the info mate. I have E32 750 LSD's for this vehicle (3.64 and 3.15 ratio's), both have the CV style nose on the diff however. I am planning on having an adaptor machined to use a 1350 Uni on the diff front bolting to the CV input flange as I've had good success with these lasting on my E32. The CV's however only last about 1.5-2 years on my shift kitted 400rwhp E32, so I will not be using one on the E30.

I believe you made have assembled a large case diff for Dan (2jz e36) over here. I think my 3.64 will go nicely in the E30 though I'll need to pull it from the 32 to put it into the 30.

[Wanganstyle]

Thanks for the info mate. I have E32 750 LSD's for this vehicle (3.64 and 3.15 ratio's), both have the CV style nose on the diff however. I am planning on having an adaptor machined to use a 1350 Uni on the diff front bolting to the CV input flange as I've had good success with these lasting on my E32. The CV's however only last about 1.5-2 years on my shift kitted 400rwhp E32, so I will not be using one on the E30.

I believe you made have assembled a large case diff for Dan (2jz e36) over here. I think my 3.64 will go nicely in the E30 though I'll need to pull it from the 32 to put it into the 30.

Cool beans sounds fun!

The e24 m6/e28 m5 4 bolt flange just pops on; OEM ADAPTER :)

I built a 210mm high power diff to handle 800rwhp for Dan's 2jz+76mm turbo :) it has full custom high stress internals and center capsule with high oiling modifications.