Thread: Diff Lock

From you user name I assume you have a TD5 130, which has an LT230 t/case.

If you look at how the diff lock works in an LT230, the lever has an infinite number of positions between fully left and fully right.

There is a linkage between the lever in the drivers cab and a lever on top of the front extension on the LT230. Land Rover has devised several variations of this linkage over the years - ranging from ok to very bad engineering (and not necessarily getting better as years advanced). All in my experience have thin wall plastic bushes that wear out. With some, correct adjustment and replacement of worn parts to eliminate lost motion is important.

Inside the extension housing, the difflock lever pushes against a spring. The spring pushes the selector fork to engage the diff lock, once the dog teeth are in alignment. So if the lever in the cab is fully left, the dog teeth may not have aligned, and not be locked.

The spring also has to push against the indicator lamp switch. If the switch is adjusted a smidgen too far down, or is sticking, it can prevent the diff locking (regardless if the lamp is illuminated).

I suggest looking for 2, 3 or more positions is miss-directed.

First of all I would would look underneath where the linkage comes from the top of the gearbox to the top of the extension housing on the LT230. Give everything are good wash if there is a deal of mud and crap there, then spray liberal amounts of your favourite spray lubricant at the connecting and pivot parts of the mechanism. Also spray the diff lock switch.

Operate the lever several times and repeat the lubricant spay.

Get someone to operate the lever, while you watch what is happening, looking for lost motion - motion at the lever in the cab that is not producing proportional motion at the lever on top of the front housing of the t/case. The lost motion can be due to tilting or twisting of the intermediate lever where it pivots on the side of the gearbox (the plastic bushes that wear). This lost motion is made worse when the different parts (including difflock switch) are not free to move.

Thanks everyone for your help