300SDL transmission mount replacement?

[83w126]

I don't remember it being difficult at all on the 300SD I used to have, but it looks like on this one you have to pull the flex disc to get the nut off the top of the mount. Does that sound right? Or am I missing something.

[Diseasel300]

I did mine without removing anything other than the crossmember. If the mount is really compressed, the only way to get the nut off is to lift the transmission or lower the crossmember to give clearance.

[83w126]

Hmm, I took the cross-member completely out and was able to put a 17mm open end wrench on the nut and bend the wrench open without the nut even moving at all, and the flex joint is in the way of using a socket or box end. Weird that it would be stuck because this car is 100% rust free and nothing else has even been remotely difficult to take apart.

[cmac2012]

Hmm. Blowtorch maybe. Sometimes locking a vice grip hard on it the right direction so you can take a hammer to it has worked for me.

[vollpreuss]

Luck of draw in my opinion. My SDL was rust free too. However, I could not budge the nut either. I soaked the nut in PB Blaster and took it to a mechanic. In the end, heat, vice grips and hammering was still needed to get the nut loose. The flex disk did not need removal as part of that effort.

[Alec300SD]

Avoid the vise grips, you'll ovalize the nut, turning it into a locknut.

Use a sharp chisel and a small hammer.
Use quick sharp raps with the small hammer to let the chisel get a bite on the sides of the nut.
Eventually the nut will begin to turn.

Destroys the nut, but you'll be able to remove the part.