rear crossmember

[dwd]

I am about to fit new rear crossmember & have plasma cut the old one off. have searched forum but cant work out how much of the original chassis I leave. Does the old original box section have to slide inside the new box section. I know the extension pieces have to cover the old chassis rail box section but not sure if the old metal has to go inside the new or does it butt up against the new? Thanks in advance for any help here.

DW

[daveturnbull]

It depends on what replacement crossmember you have bought. Normally there will be a few inches of old metal inside the new. The extension pieces should be big enough to allow them to slide over.

[Scotts90]

The ones I have changed all slid over the old chassis legs to give a sleeved fit. You should be able to work out how much needs to be trimmed from the old legs to give a snug fit...if you measure what you have cut off and transfer that across onto your replacement. There's a guide in the tech section that's handy to have a read through.

A few holes in the sleeves for plug welding onto the old legs that are inside then a complete seam weld around the joints makes it nice and strong.

[robhybrid]

I always cut off the section that cranks out to make the sleeve, have a simple jig to transfer the measurement of new chassis extension to the original chassis. I think it's always best to try and keep as much of the original chassis as possible.

I sleeve the join internally and try and make it that you cant see my repair, I do about 12, 90 rear cross-members a year I have a supplier of rear cross-members that fit well and look damn near original.

The amount more they are than britpart is well worth it as I don't have to spend extra time making them fit.

[Anderzander]

On my old 90 I left all of the rails intact - though had to rebuild quite a bit on one side.

It then slid into the genuine crossmember and, practically speaking, made for an invisible replacement.

[dwd]

Xmember now fitted. I found that the corners were holding it off & needed shamfeering to get a good fit. Despite measuring twice it still needed offering up & fine adjustments made with grinder. Now its welded in place I can see that there is no way the old box section will go inside the new box section. Thanks everyone for your time.