Hello,

Today while doing my drum brakes I noticed that I have a pinion seal leak on the differential.

Has anyone done this before? Is it a big job?

How did you make sure the pinion nut preload wasn't affected during reinstallation? I've heard of different strategies. Some say record the angular position and number of threads poking out from the pinion nut and do the same during reinstallation. Others say record the undo torque with a torque wrench and use the same when installing. I guess you could probably use a combination of the two.

I'd be interested to hear from those who have done this job!

 

Mark the nut and the yoke, so you know their positions relative to each other, count the number of exposed threads from the mark on the nut. Use an inch-pound torque wrench to measure torque required to turn the pinion. (preferably with the axles removed......) Do the seal swap thing, and put the pinion nut back, getting it as close to where it was before... re-measure rotation torque. if it's a bit looser, give the nut another tug. If it's really close, leave it. Not a bad job...... but, easy to screw it up. (don't use an impact to put the nut back on... WAY too easy to go too far with it.)

 

Thanks. When you say measure the torque required to turn the pinion, you are talking about the pinion nut? If so, are you talking about measuring the torque of the nut when trying to undo it? Or when trying to tighten it?

I was going to put the handbrake on, then this would ensure the position of the gears are fixed and also so I can reef on the pinion nut and not have it moving around.

 

E-brake won't hold things in place. You will easily overpower them trying to take the nut off.

You are more concerned about how much torque it takes to turn the pinion itself. (and everything after it as well, which is why having the axles out is preferred....) That is the important spec. You want to be as close to that as you can get when it's all back together.