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Removing the Transfer Case:

...I don't have any concerns about rebuilding the case once I get it out (at least not yet) but would like to hear any tips that might help expedite its removal.

On my '97, the rear driveshaft was a real PITA to remove the first time around. Eventually, I figured out that by dropping the main tank an inch or so (careful about the lines/fittings on top) and some judicious and gentle prying, it can be removed and installed relatively painlessly.

Unless your truck has a body lift, you'll be able to get to the top couple of bolts which couple the transfer case to the transmission adapter a lot easier if you drop the tcase a little bit. Support the transmission under the pan with a bottle jack or other adjustable device (make sure to distribute the load with a wood block or some other means), remove the block which attaches the transfer case to the transmission cross-member (or, remove the cross-member entirely), and drop the case an inch or two by lowering the jack a bit.

A few special tools will make the task easier. First, a ratcheting 9/16" box wrench, if you can find one that will fit inside the webs on the case. Second, the Snap-on ratcheting 9/16" box with 90-degree handle. Finally, a 9/16" 2" long or so torque extension. I have the Snap-on spline version, and it works just fine on splined, 6-point, or 12-point fasteners. It'll be obvious what these are useful for as you try to remove the tcase from the tranny adapter. The job can be done without the special tools, but they do make it easier.


Removal is not too difficult. Some of the less-obvious points...

Disconnect both drive shafts. (remove rear)

Remove cross-member, allow trans/t-case to drop down for access to the upper nuts (Support with jack, remove support, slowly lower the jack, etc.).

T-case is attached to the transmission by 6 nuts (9/16") on six studs. Leave the adapter on the tranny.

The easiest way to disconnect the t-case from the "cable thingie" is to remove the nuts holding the bracket to the t-case bolts.

Remove the cable harness retainer from the bracket on the top of the t-case

Remove the vent line from the fitting above the shifter area (I usually have to unthread the nipple fitting from the "T" fitting)

All of the fasteners that attach the t-case to the truck are inch sizes, and all of the fasteners on/in the t-case itself are metric.

To rebuild the t-case, some special tools are required:

  • a 12-pt 10mm socket

  • a _large_ retaining-ring plier

While you are inside, you should consider rebuilding the diff with the upgraded pinon gears. Cost is relatively minor.

When you go to remove the diff from the main shaft, beware the 50+ needle bearings! They can make quite a mess. I would recommend partially removing the diff, then placing a rubber band around the needles to keep them in place.

After around 50k miles, be sure to check the chain for wear. Many people replace them as a precaution.

Dave Breggin
'95 Diesel Wagon

> Ok... so i've read whatever i can find, but it still confounds me how to get
> to the top passenger side bolt on the T-case. I dropped the gas tank, all
> the heat sheilds, but it still baffels me, i have everything else off the
> case, that's the last thing i have to do, and i cannot figure it out.  Do
> you need specilized tools, and which side do you go in from?  I have a 95
> truck.   Also, I noticed something weird.  I bought a new T-case from
> someone who no longer needed it, and an interesting thing is that it has a
> smaller rear shaft than my T-case has?  Other than the smaller rear shaft,
> and a different main shaft, everthing seems similar.  The new T-case tail
> housing cover is held on by 3 bolts, as per the pictures in my 95/96 CD
> (looked at both years)  However, The old T-case in the truck has 4 bolts
> holding on this same cover, and a larger mainshaft. Can't get the part
> number right now, but will the next time im under if anyone is confused.  I
> plan on swapping out parts, shouldnt be too bad..
> Hopefuly someone can help
> Luke

I have had my T-case out many times, and would be happy to help.

I don't know whether you are removing the T-case, or removing the rear half "in place". Regardless, my recommendation is the same. While supporting the transmission with a jack, slowly lower the transmission and T-case several inches in order to be able to access these bolts. I have always left the adapter in the truck, attached to the transmission. Also, there is a drain plug in the adapter, but I could never figure out how to open it with everything in place. I mention this because where there is a drain plug, there is the opportunity for "bathing". The volume of the adapter is small, but there is usually a small amount of ATF in there. I did not have to remove my fuel tank.

You mention a smaller rear shaft - do you mean the output tail cone, or the shaft itself. If it is the shaft, you will not be able to use this T-case. If this is not a "Hummer" T-case, do not use any of the parts. There are several internal differences, and many are not obvious.

There were differences in the tail cone (covering all or some of the main shaft where it connects to the rear drive shaft). A friend with a '94 mentions that his is shorter (no long rubber part). On my '95, and on all of the later models that I have seen and on my spare T-case from '98, the rear tail cone is held on by 4 bolts and is as long as the main output shaft. I don't recall what my manual says, but I seem to remember no differences.


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