Coolant in rear diff

[M1028A1ShelterCarrier]

Hello,

While changing the fluids on a new to me 2012/M1167 from GP, I found oil in my rear diff that looks like a milkshake. I also noticed that the vent line was also removed/hanging. I drained to diff and waited till the next day to see is the cooling system is leaking. Sure enough, I drained coolant from the diff the next morning. So here are my questions;

1. Can these cooled covers be serviced or is it trash?
2. Does the truck coolant system have to be drained and brakes removed to swap covers?
3. Can they be found for less then a couple $200?

Here is a picture of my cover. I could not find this procedure in the latest TM or M1167 TB.

 

[Retiredwarhorses]

It’s pretty straightforward, it’s just a little radiator inside, I had this happen on my m1152, I looped the glycol lines and called it a day.
the diff cooler is overkill

 

[MarkM]

Was the vent line capped off? Hopefully it was just the cooling coil in the cover so yes you could just cap of the ends going to the cooler and connect the two coolant lines together. This can also happen in the transfer case as well as other coil coolers and is commonly called a vampire leak.

These are problematic as tranny fluid fills up the transfer case and flows out the vent lines to everything that system is attached to. Can make a real mess and lowers your tranny of fluid and that causes it own issues.

Mark

 

[M1028A1ShelterCarrier]

The vent cooler was not capped off but all other fluids looked good when flushed. I will probably end up swapping covers to keep it OEM. Thanks!

 

[osteo16]

Side question... where does the diff fluid go? Back to radiator? Thx