2005 Mahindra 2615 HST 4wd.

[Mapp]

I have a 2005 Mahindra 2615 HST with 480 hours. I am the original owner. When i push the locking differential pedal down, it does not seem to lock the rear wheels and the pedal does not come back up on its own as it is supposed to. I have to grab the pedal with my hand and pull it back up. Could the clutches be damaged? Does anyone know how hard it is to get to the parts to see what is going on? Can you access the parts from the top of the case, under the driver seat? I tried going forward and reverse, pushing the left brake and right brake, etc and pedal would not come back up on its own. Matter of fact I am fairly certain the rear wheels did not lock in when i initially pushed the pedal down so would appear locking differential is not working at all, with pedal up or down. Any help would be much appreciated.

 

[DavesTractor]

I just answered this where you posted in the general forum. You might check that reply.

 

[Mapp]

Dave, let me ask you, why do you think the pedal sticks but the rear differential is not engaging? Could it be 2 different issues? the clutches in the differential are damages but the pedal is sticking from non-use? Thanks in advance for your help.

 

[DavesTractor]

Forget for a moment that the pedal does not come up like you expect. Are you certain the diff lock does not engage? Let's assume the answer is yes, you have properly tested and the diff lock is not engaging.

Yours is an HST so the pedal is on the left and it attaches to a rod that goes through the transmission case and exits on the right side of the case. It has another pivot and an adjustable link on that side with left/right hand threads, like a mini turnbuckle. If all of this is free and working well, then you can try to adjust the turnbuckle shorted, so it pulls the diff lock in further. If the cogs are not rounded off and your linkage is not sticky, this will make the diff lock work. Removing the tire might help gain access, or reaching in from the back.

If you get it to engage but it really wants to pop out even with some pressure on it, the cogs are rounded. It is about 2-3 hours labor to remove the right side axle housing and replace the rounded off cog. It is made softer than the differential so it gets damaged before the differential gets damaged. You will need to replace the hy-trans and both filters.

Back to the pedal not coming up, keep in mind that it only pops back up about an inch. Yes you can pull it up a couple of inches, but that does nothing, just wasted range of motion and some folks focus on that and worry that it won't come back up all the way....but it isn't supposed to. It is only important that it release enough that the cog inside is not resting on the diff cogs. There is a spring that does that. This adjustment is not tricky.

I hope this helps, let us know.