So I was under my dads dakota replacing his shocks today and I noticed that there was differential fluid coming out of the front of the rear diff where the driveshaft goes in. Could there be some seal that has gone out? What could be causing this slow leak of fluid? btw it is a 2000 sport ext cab with the 4.7 and 3.55 gearing in the rear.

 

Sounds like the pinion seal has gone bad, or has been crushed.

 

So, would this be a quick fix for a shop. Like would it not be too expensive to get this replaced and have the diff fluid changed?

 

I am not sure what a shop would charge as I do all of my own work, but it should be a fairly easy in and out job for about any shop. Shop around and get the best prices and ask around for the best shops. The best advertisement is word of mouth, and if alot of people have gone to one shop in particular, it is for a reason.

 

I just had mine done last week for $100.

 

100$. Not bad, ya I think we will have it done within the next week...don't want all that fluid leaking out. We have a good shop in town that we will take it to.

 

I do all my work I dont believe in shops for my truck and it is a pinion seal its really easy disconnect drive shaft,take pinion nut off take screw driver and pry seal out put new seal in and put back together usually I take this time to change the fluid also.

 

It is a really easy DIY task. Make sure to spray some penetrating oil the day before on the bolts of the rear drive shaft at the flange (Do this and life will be good). You can get to that seal from the outside of the housing w/o taking anything apart (except for dropping the shaft and taking off the nut). Obviously this is also a good time to change the fluid since you're already going to lose quite a bit by taking the seal out. You might as well drain it first through the plug hole. You'll need something to hold the flange still while you're taking this nut off (strap wrench can work for some types). The seal literally costs like $18 for the "good" one. Then some of your time (perhaps bonding time with the dad), and you're done.

 

I'm old and arthritic, but I'll change pinion seals and change gear grease all day for $100.00 a pop.

 

Yeah, very easy job. It took me about 15 minutes to change mine out start to finish, but I have a large selection of air tools (the pinion nut is tightened to 210 ft*lbs, so good luck getting it off by hand... you might want a 2-3 foot breaker bar). And again, you will need a torque wrench to put the nut back on that will go up to 210 ft*lbs.

It is VERY important to tighten the pinion nut down very accurately and DO NOT overtighten it!!

In my honest opinion, a shop will try to screw you on the job just because it involves something in the rear axle. The $100 price isn't bad if that included the seal, new fluid, and a cover gasket with labor but most shops will probably charge a lot more.