Trans fluid leaking to TC

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meir

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Hello Guys.
just finished installing a crate engine in my truck after 4 years of seating in the driveway.
when I started the job, I noticed a fluid leak under the transfer case, so I removed it and resealed it.
before removing the TC and before draining it, I opened the filler plug, and a significant amount of fluid came out (unfortunately I didn't measure it). I didn't give it much thought.
after installing it back on the truck I filled it with 1.3 liters of transmission fluid as instructed in the workshop manual.
I checked the level of the transmission fluid and it was empty. I needed more than 5 quarts to fill it up. so the transmission was dry.
the transmission was rebuilt about 500 miles before the old engine died and the truck was parked.
no leaks from the transmission or transfer case at the moment, but the transmission is losing fluid.
I drove the truck for about 50 miles since I finished the truck and check the transfer case fluid level this weekend.
sure enough, 1/2 quart of fluid came out of the filler hole (this time I measured). so there is definitely a fluid leak from the transmission to the TC.
the question I have is regarding the seals.
I'm probably going to drop the TC again and replace the input shaft seal (and all other seals), but was wondering if there is another one I should worry about on the transmission side.
the truck is 89 K1500 with 700R4 transmission and 241C transfer case.
Thanks in advance.
Meir.
 

pressureangle

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No replies here, so I'll jack the thread.

Pulled the filler plug from the Tcase and got... plenty. So trans is leaking in, right?

Does it really even matter? I have no leak at the driveshaft seal- yet....
 

scott2093

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Does it really even matter? I have no leak at the driveshaft seal- yet....
Apart from the obvious levels of the transmission I've read maybe some issues with aeration if using 4wd and it being over full...
I'm interested in hearing..
I'm still confused on to how it all works as it relates to the adapter. From what I understand there is a drain back to the transmission pan that should keep things in check but I really don't know and it doesn't jive with the more prevalent stories of the transfer case becoming over filled when things get to that point..
 

joeblow867

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No replies here, so I'll jack the thread.

Pulled the filler plug from the Tcase and got... plenty. So trans is leaking in, right?

Does it really even matter? I have no leak at the driveshaft seal- yet....
How much do you care about the truck? If it was my rust bucket winter beater, I wouldnt worry about it. It will only be going maybe 2k miles a year and i dont use 4 wheel unless I have to. Close to ten years ago a friend bought a ZR2 S10 that the seal between the trans and t case was shot. Previous owner had a quart oil jug rigged up to catch the fluid tucked back in a spot where you really couldnt see it. It was worth fixing on that truck because the 4wd wasnt working. Had the 4x4 worked, if it was me, I probably wouldnt have fixed it. But on the 97 I just bought that i plan to have until i die, yeah, id fix it on that.
 

pressureangle

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Spoke with my transmission guy yesterday, his opinion is 'Nobody ever notices it until it starts coming out the vent anyway- don't worry about it unless it makes a mess, just be sure the trans dipstick stays up'. Since this is a local-duty truck anyway and 4x4 will only get used for boat ramps, I probably won't spend the energy unless it spots the driveway.
 
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