Opening the Diff

[bigred85]

I am going to seem like the moron that I am, but what the heck.

I know the best way to check the gearing in my diffs is to take the covers off and count.

My question is......How do I do this??? /forums/images/graemlins/dunno.gif
Are there any tricks? What kind of oil do I use to refill them?? Thanks.

PS I have a 10 bolt.

 

[84gmcjimmy]

unbolt all the bolts on the diff cover, get a slot ended screw driver and pry the cover off (if its been sealed with something) MAKE SURE YOU HAVE SOMETHING UNDERNEATH TO CATCH THE OIL! and then fill it back up in the filler spot with gear oil /forums/images/graemlins/waytogo.gif

 

[bigred85]

Is gear oil standard, or are there different grades??
Do I need to replace a gasket or anything like that?

 

[84gmcjimmy]

You may want to put a bead of silicon around where the bolt holes are to seal water out, and oil in. I don't know what kind EXACTLY of oil to use, I haven't changed the oil in mine yet /forums/images/graemlins/yikes.gif

 

[stallion85]

Start loosening the bottom bolts and work your way to the top, do not remove all bolts then pry it off! You will have a big oil spill on your hands /forums/images/graemlins/grin.gif Just loosen and let drain out of bottom. Before you put new oil in clean out with break cleaner really well. I use 85W-130, I think /forums/images/graemlins/confused.gif Also check out some ring and pinion websites, they will have calculators to determine you gear ratio. try this one

 

[84gmcjimmy]

[ QUOTE ]
You will have a big oil spill on your hands

[/ QUOTE ]

Thats why we're men, we are meant to get dirty... /forums/images/graemlins/histerical.gif

 

[m j]

remove all the bolts except one on each side, not the lowest ones but the ones just below axles centerline
place a pan that can hold over a gallon under the dif
loosen the 2 remaining bolts a couple of threads, you will use these to control the flowrate of the fluid that you are going to release
a soft mallet and a prying device should break the gasket/silicon seal
drain the fluid, dispose of it legally
while you are counting the gear teeth (and recording any numbers that you find to post here) look for evidence of a posi/limited slip/locker
clean it up a bit with brake clean
get the gasket surface spotless

for refilling you can use an 80w90 gear oil
if it has a posi that requires friction modifier you need to add that as well

 

[k20]

there are different viscosities of oil like motor oil, i run 85w-140, being in texas, that is prob the thickness u want to go w/. Thicker less mileage, better protection etc. Only probs w. thick oil of course is when it gets super cold, gets like glue and wont protect the gears.

 

[ugly_blazer]

[ QUOTE ]
Is gear oil standard, or are there different grades??
Do I need to replace a gasket or anything like that?

[/ QUOTE ]

I always buy the gasket when I'm at the parts store buying the oil, it doesn't cost much more than the blue rtv silicon.

I think a 10 bolt may take 2 quarts of oil, anyone know? /forums/images/graemlins/thumb.gif

 

[K5MONSTERCHEV]

Forget a gasket, ust use RTV. If it has a gov loc dont forget to put additive in.

 

[bugspray]

Someone suggested to me to loosen the fill plug before opening the cover. GREAT idea!!!

 

[jekbrown]

jekbrown's 10 steps to a diff gear oil change:

1) put oil pan underneath cover.

2) remove all the bolts except the top one... take it half-way out.

3) use a screw driver to pry the bottom of the cover open, oil will now spill out into the pan.

4) when mostly done draining, remove the last bolt and pull the cover.

5) let the thing sit there for a while so all the oil that can come out will.

6) whip out some brake cleaner and spray down the inside of the diff, cleaning things up.

7) use a putty knife, or drill + wire wheel or whatever else you need to remove ALL of the old gasket from both the cover and the mounting surface on the diff.

8) apply a bead of RTV as per its instructions going around the entire perimeter of where the diff cover attaches, including going around each and every bolt hole.

9) line things up, and gently press the cover on so the bolt holes line up.. put in all the bolts, ensuring that you don't torque them down so much that all of the RTV is pushed out.

10) pull the fill hole's square-headed-bolt from the diff cover, and refill the diff with standard gear oil available at any auto store. You know its full when it starts to ooze out of the hole. When done, you ought to be able to stick your pinky in the hole and touch the surface of the fluid.

j

 

[bigred85]

Now I remember why I love You Guys!!!!
Y'all are the greatest!!! /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif /forums/images/graemlins/thumb.gif
Thanks