Replacing Front Differential Seals

[ColoradoSilverado]

Aynone ever done this ? Both output shaft seals are leaking, do I need special tools for this ? Seal are only $10 a piece.

Bert

[j cAT]

[quote=ColoradoSilverado]Both output shaft seals areleaking




It is normal for these seals to leak slightly....a dripping condition would reqire the replacement but if these just create an oil dampness in this area it is not necessary to replace... my seals started to indicate an oil film/ dust at about 20,ooomi and now at 120,000mi same condition also as temps change the oil seepage varies...

what is important at the checking of your fluids every oil change do you find you need to add ...if so this also would indicate a seal replacement...

filling the gear box is to 1/2 inch below the fill hole and also clean/test the vent for no restrictions as this can also create pressure in the box..

[ukrkoz]

pm me later tonight, i'll send you instructions. all you need is seal puller, but a screwdriver works as well. easy job. large socket to drive them back in.

no, your truck is not supposed to "gently leak". closing on 100 000 miles on mine and not a dampness. i, personally, have no beef with a dirty truck, but leaks and me don't go along too well. dampness today, puddle tomorrow.

[ColoradoSilverado]

Originally Posted by ukrkoz

pm me later tonight, i'll send you instructions. all you need is seal puller, but a screwdriver works as well. easy job. large socket to drive them back in.

no, your truck is not supposed to "gently leak". closing on 100 000 miles on mine and not a dampness. i, personally, have no beef with a dirty truck, but leaks and me don't go along too well. dampness today, puddle tomorrow.

My truck is at 172,000 miles now, I guess it's not really dripping more like sweating. It just collected all on the skid plate so there was a puddle of oil.
I have to powerwash the underside of the engine to see how bad it really is but i'm pretty sure I want to replace them anyway.

Bert

[j cAT]

[quote=ColoradoSilverado]My truck is at 172,000 miles now, I guess it's not really dripping more like sweating. It just collected all on the skid plate so there was a puddle of oil.
I have to powerwash the underside of the engine to see how bad it really is but i'm pretty sure I want to replace them anyway.

Bert

The important fact here is at every oil change how much is required to bring the gear box up to the 1/2inch below the fill hole...if its using 1oz...why bother,soon you may be replacing the transfercase or front differental with the mileage you mentioned..also as I stated earlier the vent must be clear and the box not over filled..

this then would be the time to attack any other minor problems...


80-90wt gear oil does show a greater display then regular motor oil..when leaking a small amount of this gear oil looks bigger than it is...


In the transit industry gear boxes leak and the amount of oil added is the determining factor as to overhaul..

[ColoradoSilverado]

Got one more question: after I unbolt the front drive shafts from the differential, how do I get the axles out of the differential ?

Bert

[ColoradoSilverado]

Still like to know how to get the shafts out of the differential, you just pull them out ?

Bert

[j cAT]

[quote=ColoradoSilverado;5924771]Still like to know how to get the shafts out of the differential, you just pull them out ?

Bert

I have never replaced the shafts on this vehicle BUT on other vehicles a large flat blade screw driver as a pry tool and with this between the gear box and axle pop off..

when installing you need to give the axle a good hit to lock in place...

[Reflash]

I'll add a word of caution...be sure to turn on the ignition and engage the front axle. Spin the front axle by hand or drive it a few feet forward and back. If U dont do this, U stand a very good chance of dropping a washer inside the axle assembly when U remove the axle and will have created more problems for yourself

jcat is right...a pry bar will remove them with a little brute force when prying. What I do is use a hammer on the inside of the flange and one good rap will release it. Same for installation...one good rap on the outside of the stub shaft flange to seat the snap ring is all thats needed.

[sierra99]

[quote=ColoradoSilverado;5924771]Still like to know how to get the shafts out of the differential, you just pull them out ?

Bert


I went to my local parts store and rented (free for 2 days) a slide hammer and an adapter to attach to the inner shaft. The only problem I had is that the slide hammer was too large to get between the shaft and the left wheel assembly. I went to my local harware store and bought a 14" bolt and 2 nuts and used that as my slide hammer instead of the slide hammer that I rented. I just put the slide hammer slide weight on to the 14" bolt and then threaded that into the rented adapter to the inner shaft. 2 slides later it was out. All there is, is an "C" clip on the inside of the diff holding the shaft in. I tried to pry it out like others had done here, but I did not have any luck with that. Hopes this helps.

[ColoradoSilverado]

So, for the passenger side axle I have to unbolt the tube from the differential before I can remove the axle right ? And the driver side axle just pops out with some help ?

Bert

[Reflash]

No...what U need to do is unbolt both front axles, the front driveshaft and the axle assembly mounting bolts from the passenger side and the upper bolt on the drivers side. Then loosen the lower bolt on the drivers side, dont remove it...the one directly under the engine oil filter...and lower the front axle using a floor jack. I use a lift for that kinda work and use a hi-boy or a screw jack. It'll rotate and pivot on that rear lower bolt, which will allow U to remove both stub shafts to replace the seals. Just be sure to keep the ignition turned on and the 4X4 engaged while doing the work. Hook a batt charger to the batt if your concerned about it going dead.

btw...U also may have to turn the steering all the way to one side to allow the upper portion of the front axle to clear the steering linkage

[ColoradoSilverado]

Well, I finaly got it done, both front output shaft seals and the front and rear transfer case seal (see other post). I ended up dropping the complete front differential like ReFlash said, much easier to work on like that. The front transfer case sealended up being the wrong one (too small) althought it's the only one they offer, ended up going to Napa and got a $44 seal that went on thight. I have not found out what the noise is coming from the drive train (see other post) I did see however that the driveshaft carrier bearing holder (the rubber part) is pretty much toast.

Bert