My daughter's car was noisy and sounded terrible. Local to her shop diagnosed engine mounts. I didn't feel like doing engine mounts, so I got them to do it... went over estimate by a bit: $2000 instead of quoted $1600. Part of that was cost of exhaust clamps they had to replace, and part was including the diagnostic charge even though we elected to get the work done with them.

After it was done, still noisy, and they advised not driving it because the transfer case was shot. They wanted $2600 for a rebuilt; I had previously rebuilt the one in my ML320, so I decided to do it myself instead.

So, a couple of pointers I'll reshare here, in case it helps someone else, or in cast I have to do another one someday and need a refresher:

1. You don't need to remove anything other than unbolting the two driveshafts from the TC and the TC from the transmission (8X E12 bolts). When I did my ML320, I had removed the transmission mount support, which meant I had to support the tranny, but that did make access to the TC bolts easier. Without removing anything else, the top passenger side bolt is a bit of a pain, and the top and next to top driver side ones are even more of a pain. Although you can't see them, you can easily get your hand on the top two bolts by reaching up from behind the TC. For the passenger side one I needed to use a U joint and close to two feet of extensions. For the top driver side one, I needed two U joints and even more extensions, to use the ratchet (with a cheater bar on it) up near the bell housing... I thought I was going to break one of the U joints, but, finally that bolt broke free. The worst one was the next to top on the driver side. For that one I had to use a stubby 3/8 ratchet, no extensions, and reach up from behind the TC. Without the transmission support in place, that one would have been easy, but this way it took all the force I could apply to that stubby ratchet to get it loose. While under there, I noticed a bunch of stuff the shop that did the engine mounts forgot to tighten (at least one exhaust bracket, and all the plastic nuts and retainers for the driver side plastic that covers the transmission mount bracket). P.S. unbolting the front driveshaft from the diff doesn't buy you anything because you can't remove the driveshaft while the TC is in place (unless you have removed the transmission support).

2. You do need (I think) some special retaining ring removal pliers to remove retaining rings from the shafts in the TC. These are split rings with no holes or anything, just a narrow round or rectangular cross section spring with a gap for the pliers.

3. An inside bearing puller works well for the blind hole bearing that supports then end of the front output shaft.

I am currently waiting for those retaining ring pliers. When I did my previous one, I took the pieces to a shop to have the bearings swapped.

This TC had basically no oil in it, and, once I removed the differential, I could see the main problem: the rear output shaft bearing was missing half of its *****. They weren't floating around in the case, either, so they must have been ground up along the way! The diff itself looks OK. The front output shaft blind bearing had some binding spots when turned by hand, but wasn't visibly bad, like the other one. I think the TC will be pretty good once I've got the new bearings and chain in there... and some oil, and new seals to keep the oil inside.

 

Thank you for sharing. I assume a lift is needed to have enough room to remove the TC. What parts did you replace?

 

No lift needed. Just jack stands... mainly to get the wheels off the ground so the driveshafts can be turned to access the bolts, and to give me a bit of room to work.

I will be replacing all the ball bearings, some of the needle bearings (although, they mostly seem OK), all the seals, and the chain.

 

Not sure if you do this already, but when I did mine, I used a heat gun to heat the case or shafts, or bearings as needed for install and removal. Expanding the case allowed cold bearings to fall right into place or come out easily. Heating a bearing and cooling a shaft allowed for the same ease of work.

I figured I'd add that incase it helps you or someone else that finds this thread.

 

There is a great how to in the x164 section with pictures. First of three threads: https://mbworld.org/forums/gl-class-...art-1-3-a.html

 

I froze a bearing and a bushing for install, but didn't try heating things, since working with hot parts is usually a pain. Did you use heat to remove the needle bearing and bushing from the chain gear?

 

Probably, I used the heat gun for almost every part if I could, it was the key to my success. I'll go back and see if I have any evidence of doing that on the chain gear bearing. Strategic heating doesn't have to be so hot that you can't handle the part. However, some gloves do help.

I looked but I don't have a video of that. I'll go back and look for pics to see if one will jog my memory. I do know that I successfully removed and replaced all bearing with only standard tools. Some of those bearings required patience and trial and error though.

 

Both the bushing and the needle bearing were very difficult to remove. I had to bore out the outer race of the needle bearing in a lathe. Since both parts are steel, I don't think heating the assembly would have helped.

 

I may have used a slide hammer with some puller arms on it for that one if I'm thinking of the correct one. If the hole goes all the way through, I removed it by angling a long rod or screwdriver, I think. Destroyed it but it worked. I like the lathe idea, but I don't have one of those unfortunately.