As mentioned in my trip report, I've got a fairly robust leak from the transfer case. It's always hard to tell with these things, and I need to remove the parking brake to get a good look, but after wiping the transmission and TC with a rag and watching closely, the leak appears to originate from the area of the shims -- between the body of the TC and the rear bearing retainer for the output shaft.
I'd appreciate any thoughts on how to diagnose and fix it.
Background
I rebuilt the TC and transmission recently, and after installation it didn't leak at all when resting. After driving it a bit, including a 100-mile day trip to the mountains, it appeared to leak only a little from the top, out of the ports for the shifter rails at the back of the transmission cover. No big deal.
After another day trip to the mountains, which included about 45 minutes of low intensity 4WD, this other fairly serious leak developed, enough to create a puddle the size of a saucer over the course of a gas stop. It leaks faster when the transmission is hot and the the gear oil is more runny. And it drips after being wiped down, whether the vehicle is running or not, suggesting it is gravity-fed and originating below the level of the gear oil.
I'm pretty certain it isn't coming from the speedometer cable connection. I've got a neoprene washer as a gasket there, and I can't see leakage in that area, though it is hard to see with the parking brake still installed.
When the shims and rear bearing retainer were installed, I put a little Hylomar Blue on the TC and the bearing retainer faces but didn't coat the shims. I also coated the threads for the bolts that hold the bearing retainer and shims in place.
Should the shims have been coated before final installation? In looking around the web, it seems that some do coat the shims (with copper spay, for example) and some do not.
In any case, I've got to get it sorted out. It leaks just a little to much to be treated as a petty annoyance.
I'd appreciate any thoughts on how to diagnose and fix it.
Background
I rebuilt the TC and transmission recently, and after installation it didn't leak at all when resting. After driving it a bit, including a 100-mile day trip to the mountains, it appeared to leak only a little from the top, out of the ports for the shifter rails at the back of the transmission cover. No big deal.
After another day trip to the mountains, which included about 45 minutes of low intensity 4WD, this other fairly serious leak developed, enough to create a puddle the size of a saucer over the course of a gas stop. It leaks faster when the transmission is hot and the the gear oil is more runny. And it drips after being wiped down, whether the vehicle is running or not, suggesting it is gravity-fed and originating below the level of the gear oil.
I'm pretty certain it isn't coming from the speedometer cable connection. I've got a neoprene washer as a gasket there, and I can't see leakage in that area, though it is hard to see with the parking brake still installed.
When the shims and rear bearing retainer were installed, I put a little Hylomar Blue on the TC and the bearing retainer faces but didn't coat the shims. I also coated the threads for the bolts that hold the bearing retainer and shims in place.
Should the shims have been coated before final installation? In looking around the web, it seems that some do coat the shims (with copper spay, for example) and some do not.
In any case, I've got to get it sorted out. It leaks just a little to much to be treated as a petty annoyance.
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