Changing speedo cable

[Shirley]

What's involved with changing the speedometer cable on an 81 300D Turbo?

[pawoSD]

Disconnect it from the rear of the transmission, from its support mount in the engine compartment, and from the back of the cluster/speedo. Pretty simple....

[bgkast]

IIRC there are some clips along the transmission too.

[lutzTD]

on the trans side there is a bolt from the side of the cable, hex head is toward the rear, I think it is a 10mm. remove the trans side first. undo all of the clips up to the firewall then pull the firewall grommet out by hand, not with the cable. make sure to note the routing and copy it with the new cable, better yet take a bunch of pictures so you dont have to rely on memory. Wash hands, then either reach under the dash and push the cluster from the back or get a wire tool or MB tool to remove the cluster from the front, pull the cluster toward the wheel carefully, just far enough to reach in and unscrew the speedo cable. dont pull the cluster hard or too far because there is an oil line going to the oil pressure gauge and you DO NOT want to cause a leak on that.... once you have the speedo disconnected remove the old cable out the hole from the engine side. thread you new cable in from the engine side and connect it to the speedo, reinstall the cluster, reroute down to the trans and install in the trans. If you get it routed right and you have a good cable the speedo should operate smoothly, if you have a bend too tight or a bad cable the speedo will jump, this is why pictures of the old routing is important. good luck

[pmckechnie]

A little trick I learned when replacing a speedo cable or anything that is long and can be put back in different ways is to tie a long string to the end of the cable (in this case) and then pull the cable out. When putting it back in, follow the string and it will be back the way it came out.
Paul