Thread: Speedo cable oil leak-LT77

I'm pretty sure there should be an O ring at the cable end where It meats the gearbox . I'd check to see if you have one !!.. Jim

Speedo cable goes into LT230 transfer box which LT77 is one of the types of gearbox which can be used in front of. It is driven by a screw type gear on the rear output shaft in front of the parking brake. This drives a small plastic gear on the opposite end of the small shaft which is square on the inside for the speedo cable to fit into. This shaft runs in a small tubular housing. The number of teeth on the plastic gears apparently ranges from 20 to 24. My '97 build Defender 130 has 20 tooth one.


This housing has a flange of the outside to stop it going in too far into transfer box housing. . ie Locate it in correct position. The little bracket holding the speedo cable secured into the housing with a 6mm bolt also stops this speedo drive bearing from coming out.


There are two things which can leak oil. There is an O ring in a groove in the bearing housing to seal it in the main housing. Probably would only leak if speedo drive removed and then replaced without replacing an old hard O ring. Then there is a small fat oil seal inside the bearing housing. They are - or should be supplied with an LT230 gasket and seal kit in case info on part number is otherwise hard to find. Most likely this is leaking from wear and going hard as oil seals normally do sooner or later.


Apparently the speedo drive housings in LT230's should be readily removable with eg pliers. However, when replacing gaskets and seals on one recently, I had to resort to finding a bit of appropriately sized steel tube to push in the hollow bit and hit it with the arc welder to give something to use a fair bit of force on with multi grips. Then when it was out, remove the weld.

Originally Posted by jimr1

I'm pretty sure there should be an O ring at the cable end where It meats the gearbox . I'd check to see if you have one !!.. Jim

No O ring, metal washer on speedo cable goes straight to the speedo housing!!!
Do you have spec on o ring?
Also views on oil type?
Syntrans 75w90??
Thanks for your reply