GT3200 differential lock not engaging

[MitchJ]

Originally Posted by Gompers

The spring pulls the lever which I can't imagine is frozen. If it's rotating at all, the shaft is fine I'm sure.

That lever rotates a fork inside there that pushes the locking collar into the diff and then pins engage that hold the two halves of the diff together. The rear axle needs to rotate far enough for the pins to slide into the holes in the other half of the diff, so you need to engage it and move forward (or backwards) slowly until it "clunks".

If something is broken inside, either the spring sometimes breaks, the fork is worn (often happens if the diff is misadjusted and constantly rubbing), or the pins are shared off the left dealie there (happens when people engage the diff lock while the wheels are spinning and it slams into place), it won't work.

Here's what it looks like in an AL transmission. Case is different but the mechanism is the same.

Thanks that is very helpful, I hope I don't have to dive into the guts of it, but it is great to see the operation.

[Gompers]

Originally Posted by MitchJ

Yes the cable it totally free, and I did not over-tighten it- just took out the slack. The lever will move upwards a little bit, maybe a 1/8-1/4".

The lever should be pulled down by the diff lock cable. It only moves down maybe 1" or so total. Not super far. The fact that it goes back up means that the spring is working properly internally.

Again, you need to have the wheels moving a little when you engage the diff lock before it will "clunk" into place. The spring on the cable is just there to provide constant tension on the arm so the fork moves the puck over and puts pressure on it so that when the pins line up with the holes it slides over and engages.

[MitchJ]

Originally Posted by Ken41

If yours is the cast iron differential like mine, the lever does not move very much. Why did you take the cable off? Is it frozen so it does not move? Get the back of the tractor up off the ground so the rear wheels turn free and move the lever to engage. Turn the rear wheels and see if they lock together, if they do it is good. A lot of times when they do not work it is because the cable is frozen.

That did it, jacked it up rotated the wheels and pushed the pedal and it locked!

It must’ve been a loose cable, thank you very much.