cowman79

I am in the process of replacing a stretched chain in my transfer case and found a stretched chain along with a broken tensioner/idler. I have a couple of questions. Has anyone repaired the broken tension/idler bracket mounts. Also does the transfer case have to come from a 450? I found two within an hour of me. One is from a 350 and the other is from a 550. Can either on of those be used as a replacement. I also have a new chain arriving friday that was supposed to be used in my case but since it looks like I might be buying a used case I was thinking about opening it up and installing the new chain. Should I install the new chain or just let it ride.

DarthVaderpa

Transfer case is the same for all three models unless you have the off-road option (2 speed)

cowman79

Update. I was able to get a used transfer case from a local salvage yard. I replaced the chain with a new borg Warner chain. Filled with 134 Trans fluid and Installed the unit. The only difference I saw in these two units was the one I purchased had a sensor bracket on the output shaft for the rear drive shaft. I think this unit came frome a gl350.

rich4368

Great jobs cowman! My 2010 GL350 (165k miles) transfer case chain is also slipping. Does anyone have simple directions on how to replace it with a new Borg Warner chain?

Max Blast

Same underpinnings as x164.

rich4368

Thanks Max! This is a great DIY video for removing the TC and changing the chain and whole set of bearings.

Max Blast

There's another vid out there showing how to just swap in the chain with the case in place.

From what I remember the back half of the case comes off, and a new chain is used on the old sprockets.
This is not recommended, as the worn sprockets will exacerbate the new chain wearing.

rich4368

Will check that out too. I will probably just remove the TC so that I can inspect the bearings and other parts. My 2010 GL350 is really sluggish right now can't get above 65mph on the freeway. The scanner showed P2463, P2458, P2459 all related to the diesel particulate filter. I think it's in limp mode which I have not driven much for almost 2 years. Been patiently waiting for the AEM fix...

eric_in_sd

Are you sure about this? I don't see mechanically how that would work.

I could see how a worn sprocket would make a stretched chain more likely to slip - and a slipping chain probably wears the sprocket rather fast - so if you are in a situation in which the chain is slipping, it probably would be a good idea to change both while you are in there. But if the chain is not slipping, that is, the chain replacement is done on a preventive basis, I don't see how sprocket replacement would be recommended.

It looks like chain replacement is easy enough that it ought to be done on a preventive basis.

cowman79

After I took the original unit out of the vehicle I found that the chain was extremely stretched and I found that the idler mounts were broken. I decided to get a unit for a salvage yard and since I had the new chain I replaced it in the the unit from the salvage yard. This unit has been installed for over a year now and has been working flawlessly. The chain is easy to replace especially when the unit is out of the vehicle.
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Max Blast

Yep. Worn sprockets will wear a new chain faster than new chain/sprockets combo will wear. You’re welcome to try but you’ll be back in there in no time.

EWT

Definitely true on a bike. If one component is worn, the other component won't mesh properly and accelerated wear will occur until the new component "fits" the old one.

Max Blast

Same principle applies

lkchris

Just a note ... Mercedes DOES NOT recommend 236.14 for the transfer case.

The recommendation is in fact 236.12. See https://operatingfluids.mercedes-ben...sheet/231.0/en or https://operatingfluids.mercedes-ben...sheet/231.1/en

236.12 ... https://operatingfluids.mercedes-ben...heet/236.12/en

236.12 part number ... https://www.mbdirectparts.com/oem-pa...oil-1989450309 reference ... https://www.blauparts.com/mercedes-t...-45-03-1l.html