How to: tranny/xcase/rear diff fluid changes
 

Text and photos copied from socalevo.net



5/6 Speed steps

**6 speed is the same except the drain and fill plugs are both 10mm.**

1. Jack up the front of the car and put a jack stand under it.

2. Get a 17mm and 24mm socket and a catch pail handy under the car.

3. Undo the fill plug first (17mm) in order to avoid glugging (don't forget the washer!!!).

4. Undo the drain plug (24mm) second and drain all the fluid out. make sure to position the waste pail accordingly.

5. Screw the drain plug in (don't forget the washer!!!) and get a funnel with a long flexible spout (4 bucks from pep boys) and stick in the side of the fill hole.

if you use just the funnel with flex you'll likely have to remove your intake in order to fill from above. if you get some 3/8" rubber hose (about 18" should do) then you can seal off the fill hole (no leaking while filling) AND you don't have to remove the intake!

6. Pour new fluid in until it starts to come out of the drain hole (It is sideways) or around 3 quarts. YOU SHOULD ALWAYS FILL WITH YOUR CAR AT A PERFECTLY FLAT OR A SLIGHT POSITIVE INCLINE (front two wheels off the ground) this overfills the tranny as apposed to underfilling it and keeps things MUCH happier!!! this way it'll take 3 bottles of fluid and there's not guessing if you had too much spill out.

7. Put back fill plug. plugs should only be hand tight, torque specs are good, but don't hamfist them on or you'll be sorry!


5 speed pics

**drain and fill
Attachment 293498

6 speed pics

**drain
Attachment 293499


**fill
Attachment 293500



Transfer case steps

1. Open the fill plug first and clean the plug, be sure to remove both the plug as well as the metal washer. When I removed my transfer case fill plug, fluid ran from the fill hole so be prepared.

2. Put the oil catch pan underneath the drain plug and slowly undo the drain plug making sure that you also remove the metal washer. As the fluid drains, you may have to move the catch pan to prevent oil from leaking to the ground. drains real fast, only .6 quarts.

3. Clean the drain plug (you will find lots of tiny metal bits attached to the magnetic portion of the transfer case drain plug).

4. Once the stream of fluid has ceased, put the drain plug back. Be sure to remember to put the metal washer back on as well. If you have a torque wrench all the plugs should be tightened to 23 ft.lb.

5. Now, take the gear oil pump and run the hose into the fill hole. it's nice to have a hose long enough so you can sit the bottle on the ground and pump. but that just means more fluid that you're gonna have to pump back into the bottle when you're finished.

ALWAYS FILL YOUR TRANSFER CASE WITH THE CAR AT A PERFECTLY FLAT OR SLIGHT ANGLE SO YOU'RE OVER FILLING IT AND NOT UNDER FILLING IT!!! ALSO NOTE!!!

6. Pump the correct fluid into the diff. just keep pumping until fluid runs from the fill hole. it should take about .6 quarts.

7. Replace the fill plug. Be sure to remember the metal washer.


transfer case pics

**drain

Attachment 293501


**fill
Attachment 293502



Rear diff steps

1. Open the fill plug first and clean the plug, be sure to remove both the plug as well as the metal washer. When I removed my rear diff fill plug, fluid ran from the fill hole so be prepared.

2. Put the oil catch pan underneath the drain plug and slowly undo the drain plug making sure that you also remove the metal washer. As the fluid drains, you may have to move the catch pan to prevent oil from leaking to the ground. drains real fast, only .6 quarts.

3. Clean the drain plug (you will find lots of tiny metal bits attached to the magnetic portion of the transfer case drain plug).

4. Once the stream of fluid has ceased, put the drain plug back. Be sure to remember to put the metal washer back on as well. If you have a torque wrench all the plugs should be tightened to 23 ft.lb.

5. Now, take the gear oil pump and run the hose into the fill hole. it's nice to have a hose long enough so you can sit the bottle on the ground and pump. but that just means more fluid that you're gonna have to pump back into the bottle when you're finished.

ALWAYS FILL YOUR REAR DIFF WITH THE CAR AT A PERFECTLY FLAT OR NEGATIVE ANGLE SO YOU'RE OVER FILLING IT AND NOT UNDER FILLING IT!!! ALSO NOTE!!! clutch type differentials require a certain amount of friction to operate without chatter, you must use friction modifier for fluids that don't already have it mixed in. that stuff stinks like fish too, so just get the stuff that already has it mixed in.

6. Pump the correct fluid into the diff. just keep pumping until fluid runs from the fill hole. it should take about .6 quarts.

7. Replace the fill plug. Be sure to remember the metal washer.


rear diff pics

**drain and fill

Attachment 293503

Can you actually overfill the gearbox, transfer case and rear diff by raising the appropriate end too much??
Is there a point where there is too much oil inside?
When I raised the front up and drained the gearbox and transfer, fluid started coming out when the fill plugs were removed which I guess means they were overfilled to start with??

I know the engine oil drain plug has a crush washer, but do the fill and rain plugs for the tranny, diff, and t case ALL have washers too? And if they do, are they the same size?

doing this in the next few days i might need my laptop so i c an read and look at pix while im doing this

Just did this. Pretty much like 3 consecutive oil changes provided you have the right tools. IMO a pump is a must. $15 will save you a world of hassle. Especially if you do it alone. And 4 jack stands > 2 jack stands.


I propose some changes to the instructions:

- 6 speed drain and fill plugs are NOT 10mm. They are a hex (3/8 size afaik). And both use the larger washers. Part # MN130495.

-a size 15/16 socket fit better over the fill and drain plugs on the rear diff. The closest metric size was 24 but IMO its a little loose.

All the drain plugs are the same size (part number above). Except the rear diff, its copper I think (MB019730). The fill plugs (except 6spd trans fill plug) use the same gasket (MF6600036).

so do they have crush washers? or can it be reused?

They aren't really crush washers. Look like regular ones. I bought new ones anyways....not like I do the drivetrain fluids change very often. Some of the washers are unreasonably expensive! $5 for a piece of round metal? :confused:

This helped me out ALOT!! Thanks for posting the "How to" with pics.

Yep....thanks for the thread! I used it via my IPhone at the Navy auto hobby shop this weekend! :beer:

A metric size 10mm is about the same size as an SAE 3/8. Both should work fine.

Its not a bolt though. You need a 3/8 hex key type head. Or allen key. You can't just take a wrench to it.

This information is the same either for a bolt or a hex key size. I didn't feel the need to specify since it was pretty clear in the first post. lol. I personally use a 10mm allen key socket.

Also curious if overfilling can be an issue. Just ordered the 6 washers in a kit that mitsubishiparts.net has for about $12. Still researching fluids. Probably going with Redline. Hoping to make my shifting a lot smoother.

DO NOT put anything in your tcase unless its diaqueen. Or you can have lovely death whine noises like me and be out $$$$ for a rebuild. The rear diff and trans are ok to experiment with fluids.

For the record I was using motul gear 300 75w90 for my 6speed, motul gear ff 75w140 for the tcase and rear diff. The trans and rear diff is ok with these fluids (as per Shep's advice) but the t case should see nothing but diaqueen. Only took 7k miles (plus many track days and drag strips) to get the death whine.

I purchased Diaqueen ATF SPIII oil.I actually asked for tcase oil but got this instead.Can i use this oil in my tcase and gearbox or do i need to only use this oil in my ACD/AYC piping?