Transfer case removal

Transfer case removal on a 90 AWD, for leak fixes

To IDENTIFY a transfer case leak, go to the Transfer case leak IDENTIFY VFAQ

UPDATE: There IS a recall out on this. If you have not received notice of it, that means Chrysler/Mitsubishi doesn't have you down as the owner of your car. If you call them and give them your address, they will be able to notify you of future recalls. While you have them on the phone, ask if there are any outstanding recalls on your car.
Numbers:

Mitsubishi 1-800-222-0037

Chrysler 1-800-992-1997

Chrysler Canada 1-800-465-2001

The recall covers inspection and replacement of the yoke and seal if leaking, and replacement of the transfer case if it is severely worn. Print the Transfer case leak IDENTIFY VFAQ and take it with you to the dealer for the recall, too many dealers are saying there is no leak when there obviously is.

Get recall info here:

NOTE that the recall only lists automatic tranny AWD cars, but that is incorrect, the recall includes automatic and manual tranny AWD cars.

If you have a leak from your transfer case, you need to fix it. If it leaks long enough, you will lose enough fluid to damage the transfer case. A transfer case costs $1800 from the dealer, and if you break down in the middle of nowhere, you may be paying that whether you like it or not. Beyond that, if it locks up, it can also destroy your transmission.

So, HOW do you tell if it is leaking? It's not hard - jack up the vehicle, crawl under it, and look near the catalytic converter. You should see the driveshaft coming out of a small aluminum casing, which is the transfer case. Look at the floorpan of the car around the transfer case. If you see a band of fluid, or it is wet, you have a leak (the fluid is being slung out when driving down the road). These leaks are VERY common.

So how do you fix it? There are actually two places it can leak, and the second one is hard to see, and often the culprit. The one most people think of is the yoke seal on the transfer case itself. The other is the yoke itself. The yoke is created at the factory with an open end so the splines can be machined into it. That end is plugged with a brass plug that is expanded into the splines to seal them. Too many cars leak around that plug. The pics and text below show how to remove the transfer case so you can replace the end seal, and seal the yoke.

Addendum: It is NOT necessary to remove the transfer case and yoke as detailed below. The MAIN reason for removing it is to check the input and output splines for wear, and to lube them with bearing grease, as the factory grease dries out and gives no protection against wear at that time. You CAN just pull the entire driveshaft off of the car if you want to seal the yoke and see what you are doing. Simply unbolt the 4 bolts holding the driveshaft to the rear differential, and unbolt the 2 carrier bearings, then pull the driveshaft back and out. It is best to support the driveshaft as you remove it, so the universal joints don't get pulled at too severe an angle, so this is best done with 2 people, OR by putting yourself directly under the driveshaft and letting it lay on you as you unbolt each section. You can also replace the transfer case rear seal while it is on the car.

Addendum from Mark: You can also try the following to seal the yoke without removing anything from the car:

Drain the transfer case fluid
Clean the back area of the drive shaft yoke where the brass plug is located. (this is the area where the yoke and drive shaft are connected with the u-joint) I recommend using brake parts cleaner or similar. Make sure the surface is free of dirt and grease. If you need to, use a brush or rag to remove the crud.
Mix a portion of JB Kwik Weld about the size of a half dollar coin and use a thin applicator to apply the mixture to the brass plug area of the yoke. I recommend using something the size of a popsicle stick. When you look at the yoke you will see the plug and a round recessed area. Apply just enough material to cover the brass plug and feather the material onto the round recessed area. It's important to make sure you coat the entire brass plug area to complete the seal.
After 3-4 hours when the JB Kwik Weld has cured refill the transfer case fluid.
What you will need:
- 1 small package of JB Kwik Weld
- Applicator (craft stick or popsicle stick)
- 1 spray can of brake parts cleaner or similar
- A rag or two
- Drip pan to catch transfer case fluid
- Fluid to add to the transfer case when finished
- I highly recommend using the Kwik version of JB Weld. This is going to be applied on a vertical surface and you will appreciate its quick set time. Mine was dry to the touch in 3-4 minutes and fully cured in 3-4 hours.

Step one - remove the downpipe (not pictured). Basically, it involves the 2 nuts on the turbo O2 sensor housing, the one bolt holding the downpipe to the block, the 2 nuts holding it to the catalytic converter, and a small bolt for the ground strap.

This is the transfer case, with the mounting points highlighted with white lines. The FILL plug has a red arrow pointing at it, while the DRAIN plug has a purple arrow pointing at it. The case has been removed from the car for clarity. At this point, drain the transfer case from the bottom drain plug - you'll need a 24mm socket.

This is the removal of the transfer case. All 5 bolts are out, and I am using a screwdriver between the transmission and transfer case to pry them apart. You basically pull the transfer case towards the driver's side of the car to pull it off the trans output shaft. The bottom white lines point to the bottom 2 mounting points.

This is the removal of the transfer case. The white lines point to the threaded bosses on the trans, and the pink line points to the locating dowel for alignment purposes.

This is the transfer case off the trans, but with the driveshaft yoke still in it. The white lines point to the top 3 mounting points.

This is the transfer case end seal, the one people THINK causes the leak. Sometimes it does, and it is cheap, so it is safest to pull and replace it. Use a screwdriver to pry it out, or better yet, use a seal puller. Tap the new seal back in by placing a pice of wood on it and tapping the wood around and around the edge of the seal, to seat it gradually and as flatly as possible.

Tapping the new seal back in using a 3/8" ratchet extension (no wood handy) on it and tapping it around and around the edge of the seal, to seat it gradually and as flatly as possible.

This is the infamous yoke, still attached to the driveshaft. You can clean it out (use up like half a can of brake parts cleaner), and then carefully coat the inside bottom plug (you'll see it easily with a flashlight, it is obviously brass) with about 1/4" of RTV. Make sure the RTV goes into the splines too, or you are doing no good at all. If you had difficulty like I did doing that under the car, you can use a circlip pliers to remove the clips on the universal joint, and pull the yoke off the driveshaft, then clean and seal it off the car. Make SURE to let the RTV dry for at least several hours, if not a full day (a full 24 hours is highly recommended), before filling the transfer case with fluid, or it will leak again right away.

This is the infamous yoke, off of the driveshaft. You can see the inside bottom plug (you'll see it easily with a flashlight, it is obviously brass, though this pic doesn't show it well) here.

If you wish to remove the yoke to work on it, use a needlenose pliers to compress the clips in the endcaps on the driveshaft, then place a socket on one of the endcaps, and pound on it until you push the opposite endcap out of the driveshaft. Then tap on the other (loosened) endcap until the first endcap is loose. Then remove the endcaps carefully and make sure none of the rollers fall out (they are loose in the endcap, only held in by the grease). To reinstall, clean the outside of the endcaps (if really rusted, you may want to lightly sand them), clean out the endcap sockets in the driveshaft, and put a little clean grease in the endcaps. Maneuver the U-joint into the endcap sockets, place the endcaps into the sockets from the outside (get both started), then tap the endcaps in until they seat far enough to place the clips back into place.

THAT'S IT! Reverse the removal instructions, start up the car, and have at it.

This document can be reprinted for personal use or reference for your mechanic(s) with no prior permission needed. It can be linked to directly, as long as you have a link to the main VFAQ page of http://www.vfaq.com, though linking to the main page instead is preferred. This document can NOT be reprinted for profit/resale/redistribution of ANY type without expressed WRITTEN permission from me in advance. Bulk copying of this document onto your web site without prior permission will not be tolerated, link to it instead.
Last modified: May 6, 2002
Copyright 1997-2002, Tom Stangl
VFAQ.COM, http://www.vfaq.com
talonts

	Step one - remove the downpipe (not pictured). Basically, it involves the 2 nuts on the turbo O2 sensor housing, the one bolt holding the downpipe to the block, the 2 nuts holding it to the catalytic converter, and a small bolt for the ground strap.
	This is the transfer case, with the mounting points highlighted with white lines. The FILL plug has a red arrow pointing at it, while the DRAIN plug has a purple arrow pointing at it. The case has been removed from the car for clarity. At this point, drain the transfer case from the bottom drain plug - you'll need a 24mm socket.
	This is the removal of the transfer case. All 5 bolts are out, and I am using a screwdriver between the transmission and transfer case to pry them apart. You basically pull the transfer case towards the driver's side of the car to pull it off the trans output shaft. The bottom white lines point to the bottom 2 mounting points.
	This is the removal of the transfer case. The white lines point to the threaded bosses on the trans, and the pink line points to the locating dowel for alignment purposes.
	This is the transfer case off the trans, but with the driveshaft yoke still in it. The white lines point to the top 3 mounting points.
	This is the transfer case end seal, the one people THINK causes the leak. Sometimes it does, and it is cheap, so it is safest to pull and replace it. Use a screwdriver to pry it out, or better yet, use a seal puller. Tap the new seal back in by placing a pice of wood on it and tapping the wood around and around the edge of the seal, to seat it gradually and as flatly as possible.
	Tapping the new seal back in using a 3/8" ratchet extension (no wood handy) on it and tapping it around and around the edge of the seal, to seat it gradually and as flatly as possible.
	This is the infamous yoke, still attached to the driveshaft. You can clean it out (use up like half a can of brake parts cleaner), and then carefully coat the inside bottom plug (you'll see it easily with a flashlight, it is obviously brass) with about 1/4" of RTV. Make sure the RTV goes into the splines too, or you are doing no good at all. If you had difficulty like I did doing that under the car, you can use a circlip pliers to remove the clips on the universal joint, and pull the yoke off the driveshaft, then clean and seal it off the car. Make SURE to let the RTV dry for *at least* several hours, if not a full day (a full 24 hours is *highly* recommended), before filling the transfer case with fluid, or it will leak again right away.
	This is the infamous yoke, off of the driveshaft. You can see the inside bottom plug (you'll see it easily with a flashlight, it is obviously brass, though this pic doesn't show it well) here. If you wish to remove the yoke to work on it, use a needlenose pliers to compress the clips in the endcaps on the driveshaft, then place a socket on one of the endcaps, and pound on it until you push the opposite endcap out of the driveshaft. Then tap on the other (loosened) endcap until the first endcap is loose. Then remove the endcaps *carefully* and make sure none of the rollers fall out (they are loose in the endcap, only held in by the grease). To reinstall, clean the outside of the endcaps (if really rusted, you may want to lightly sand them), clean out the endcap sockets in the driveshaft, and put a little clean grease in the endcaps. Maneuver the U-joint into the endcap sockets, place the endcaps into the sockets from the outside (get both started), then tap the endcaps in until they seat far enough to place the clips back into place.