Calgary Jeep Association

4x4 Related Groups => Tech Talk => Topic started by: BEZZ on February 10, 2009, 08:23:37 AM

Title: Dana 30 Pinion Seal
Post by: BEZZ on February 10, 2009, 08:23:37 AM

Hey guys, so the pinion seal is leaking a little just wondering if there is anything to watch out for when replacing it on this axle?  Tips and tool tricks appreciated as well.  Thanks in advance for the help.

Title: Re: Dana 30 Pinion Seal
Post by: BEZZ on February 10, 2009, 01:06:24 PM

I also wouldn't mind if some one could direct me to a good write up, or even give me a description of the process for measuring pre-load.  I searched the site and found an old thread about a D44 seal but would like some direction for measuring pre-load.

Title: Re: Dana 30 Pinion Seal
Post by: BEZZ on February 11, 2009, 08:14:42 AM

I think I have answered my own question here but I wouldn't mind a yes or no from some more expreienced guys.  After raising  the vehicle I remove the wheels and tires and pop of the driveshaft.  I then take a nice little 0-50 in/lbs dial type torque wrench and see how much torque is required to rotate the pinion.  Go about my seal change and then when installing my NEW nut with some Loctite I tighten it until I arrive at the same pre-load as measured. Install driveshafts, fill diff with fluid, install wheels and tires...wheel.  That sound about right?

I have read on Pirate that changing diff fluid and making sure vent lines are clear are the first steps to see if a leaking pinion seal will work. Old wives tale or the truth...I guess I'll find out.

Title: Re: Dana 30 Pinion Seal
Post by: twobits on February 12, 2009, 01:58:12 AM

I changed the pinion seal on my Dana 35C a few years ago. I'd have to get the book on the preload (12 or 22in/lb). It did take quite a bit of force to tighten the nut, used a 12 point socket so I could use the extension bar (remember this because I ended up breaking one of the sockets).

Title: Re: Dana 30 Pinion Seal
Post by: rws on February 12, 2009, 08:15:30 AM

Changing the diff fluid and making sure the vent line is clear is always a good idea.

When measuring the preload you have the right idea, however you may want to also remove the brake calipers to get a more reliable measure.

Use red locktite on the nut and on the washer behind the nut put a glob of silicon to prevent diff fluid from leaking out the splines of the yoke.

Use a real locking pinion nut,  identical to the one you took off.