Sorry for this question but I have searched to no avail on my specific question. I was about to change out the pinion seal on my front differential when I noticed that the driver side axle seal is leaking as well. I have never replaced one of these before so I am wondering how difficult it is and if anyone could walk me through how to remove the drive shaft or do I have to drop out the whole differential to replace that bugger.

Also, I opened the fill plug on the drivers side of the differential and gear oil came pouring out and looked like Yoohoo chocolate milk rather than gear oil. Is that in indicator that maybe water got in there somehow and that is why it was so full and discolored?

Lastly, and this is probably a stupid question (always had manual locking hubs before); when the truck is moving doe the front axles and drive shaft always turn as well? I know on a truck with manual locking hubs if the hubs aren't locked in the axles don't turn and the front drive shaft only spins when it is put in 4wd. I was surprised that so much gear oil is being thrown from the front without engaging the 4wd. thanks in advance.

2002 Ranger XLT 4x4, supercab, 4.0L SOHC.

 

Another question if anyone can answer. I was researching other forums about the color consisitency of the gear oil and have read that it is a common question. Some have guessed that it is due to an addititive added at the factory for the limited slip. I don't believe I have limited slip in the front, but how would I find out for sure?

 

To do the outer axle seals, you remove the upper and lower ball joint from the knuckle, remove the CV axle and then remove the seal. Its a pain to install the seal in-vehicle, so i always remove the front axle from the vehicle. Inspect the vent and make sure it isn't clogged, and inspect the sealing surface of the CV axle. If it is scored, it will need to be replaced or the seal will leak again.

The chocolate milk in the front axle and the axle being overfilled is a sure sign that water has gotten in probably through the vent during a high water crossing. You will need to remove the front axle and remove the cover, clean it all out and inspect for damage. You do not have a front limited slip and no friction modifier is installed.

Your ranger has "live axle" where the CV axles are directly splined into the hub bearings. The front CV axles, differential gears and front drive-shaft are always turning.

 

Thanks for the info. I am going to need a long weekend to tackle this project it looks like. One last question, how is the CV axle attached to the differential? Is it just a matter of using a pickle fork and hammer to separate them or is it more complicated than that? The only reference I can find is the Haynes manual I have and to be blunt it is useless.

Again I really appreciate the help. I have only had the truck for about 10k miles and so far love the truck. Switched out to magnaflow catback exhaust, K&N air filter, new plugs, sythetic oil changes, and now changing to sythetic in both the differentials since I have to replace both pinion seals. It has gone from about 14mpg average to about 18mpg. If I can get it to where I get 19mpg average I will be very happy.

 

The cv axles are held into the axle with a retaining clip...use a small pry bar or a brass punch and tap them out

 

I agree that removing the Diff would make this much much easier. I did mine with it still on the vehicle and it sucked.


If your ball joints are original I would suggest doing it Justins way and replacing the LBJ's in the process. Other wise you can get the drivers side CV shaft out by just pulling the upper BJ and then using a wheel puller to push the CV out of the hub. You will have enough room to pull the CV out.

 

While I haven't yet tackled the front diff yet I did do the rear and it is obvious that all my fluids need to be replaced. Here is an oil sample from the front after it has sat for a couple weeks now. The rear was very similar in color and consistency. Glad I changed it when I did, I am thinking that I should also tackle the trans and transfer case as well....what do you think?

 

DO THEM BOTH the ranger i inhearted from inlaws was offroaded so both diffs and transfrer case had water/oil and rusted badddddddd