Noise from the gearbox

[John in Sweden]

I need your advice how to continue searching. I have just bought a 280SL -69 a few weeks ago. Top condition but a “ticking” noise from the back of the gearbox.

The shaft is balanced, new centre bearing, new flex disc see pictures. I’ve take of the speed wire – but still get the same noise. And I pretty sure that the noise comes from “the back side” of the gearbox but I can’t really figure out the reason.

What is your suggestion?

[Benz Dr.]

I'm not positive but it looks like you may have the cross joint installed wrong. I'll have to go and look at another car and see if it's right or not.
Sometimes the screws can touch the casting on the back of the trans which will make quite a bit of noise.

[ja17]

Hello,

Looks like the cross flange may be correct, but the rubber flex disc is installed incorrectly. The index tabs on the rubber disc must be indexed on the three ears of the transmission flange. The rubber disc will not last long if left like this since alternate areas of these rubber discs are designed for compressive loading and the others are designed for tensile loading. installing the disc incorrectly reverses the loading.  Go to the tech manual for lots of photos, diagrams and information.

The new replacement rubber flex discs are universal and can be installed in any orientation. They are also more robust!

Yes, as Dan suggested check to make sure the bolts are not touching the trans rear housing when rotating.

[John in Sweden]

Dan and Joe,
Thank you for the advice so far! I will refit the disc!