Trying to figure out why my diff lock is not locking. I have had my disco for just over a year, but it had a broken CDL shifter (Broken Nylon Ball Socket). I accidentally got it to lock and get the light to come on one time before it was fixed. But right now there is no light and I don't get the jerk-jerk-jerk sharp I make sharp turns. Short of jacking up the vehicle and turning prop shafts, I am quite sure the CDL is not engaging.

I recently fixed all of that up with new parts, the shifter works great (no, its not stuck like they usually are). The truck shifts fine into low and high, the shifter moves even better and the CDL pinion is moving. As far as I can tell, I am getting full movement (see photos)




I would like to know what other factors are involved in making this thing shift properly?

Locked


Unlocked

 

when you "lock it" does it drive in gear? sometimes the light is on a delay. might take 20 ft before the light comes on

 

Usually you can feel an engagement clicking like sound. Did you replace the piece the shifter attached to? Maybe it's out of adjustment? Take the shifter off and try to turn the but with a socket.

 

Drop the rear driveshaft and lock your CDL. You'll know real quick if your CDL is locking or not.

 

Yep, I have already tried a socket with a long extension; I can turn the full lock from left to right. It's not the shifter that is limiting the the movement.

I drove all around town with it "locked" and no light. Made a few turns in an empty section of parking lot in low gear and locked and it was not jumping around.

This weekend, I will jack up all fours and turn the drive shafts and try to get a definite confirmation.

 

I could be wrong in my thinking but if its locked and the trans in neutral with the front up you still wouldn't be able to freely turn the driveshaft with the rears on the ground? But it would rather get to a point where it starts to try turn the rear shaft. So you only really have to jack up 2 wheels.

 

What about high and low?

 

Good thought.... I should be able to see just enough movement to see whats going on.

 

Hi low works fine, although sometimes I have to shift the CDL to N and then put the tranny in D then back to N and then shift the CDL. Even when I do that, it still grinds into gear once in a while.

Hope all of this doesn't mean a CDL swap.

 

OK, well confirmed it is NOT locking....

I jacked up the front tires,but it in gear, and turned on of the tires (we figured there was enough play in the driveline to test this without jacking of the rear.)

I figure that the drive shafts should turn in the same direction if they are locked... Well they don't... They continue to turn in oposite directions regardless of the position of the shifter. Further more... If it were locked, wouldn't the wheels stop turning with the rear tires planted on the ground?

I figure I may as well check/change the oil... Its about due anyway. Otherwise im stumped.