Hi, My 99 blazer ZR2 has leaking transfer case. It has RPO NP8 (236GM).

I noticed a small leak for some time now where i park the truck, but never got around to checking it out and didn't think it was that bad, but now, headed into the winter i wanted to check fluid levels etc,. All was fine until i checked TC fluid level. It was really low, maybe a tea spoon of fluid came out when i removed the fill/drain plugs... Yeah. I was shocked too! I guess the leak wasn't that noticable anymore being there wasn't any fluid to leak... LOL.

Anyway i searched thru some posts and also looked up the TSB's on ALLDATAdiy.com and verified that i needed AutotracII fluid, so got two qts from the dealer and filled the TC, all seemed fine, truck even seemed to run smoother. That was yesterday, but after parking tonight i went to install the TC guard (left it off so i could jet-spray the TC/underbelly), and seen that quite a bit of fluid was leaking out, and was actually getting all over the back rear axle and muffler area. I can clearly see that the leaking is coming from between the two case halves, so now i really need to fix the leak before i have real problems. Now that i remember, i did hear some grunting yesterday from the rear of the truck, but thought my rear brake pads were just sticking. Hopefully it wasn't the TC making that noise?

So, i'm looking for a simple way to fix the leak, hopefully without removing the entire TC... Anyone have recommondations on how to proceed? I didn't see a 'sticky' on this, so any input/ideas appreciated.

 

if you don't want to remove the t-case, and just want a quick fix..........you could drain all the fluid overnight (this will ensure there is hardly anymore in there), then clean the outside of the case with brake cleaner. when the case is all clean & dry, then put a generous amount of RTV silicone on the seam (i'd use the lt. blue Permatex), making sure you go well past the areas that are leaking. wait 'til the silicone has cured well enough that the fluid won't seep through.
this will keep you well lubed 'til Spring, then you can drop the t-case an pull it apart to seal it properly. 'til then, get cleaning...............

 

I doubt that RTV on the outside of the case will seal the leak.

The case needs to come out and be repaired properly. RTV is what is used between the case halves, but it needs to be between the case halves, not just on the outside.

 

Sounds like the only to properly fix the leak is drop the TC? If so then would you happen to have a good process document that i can follow to properly remove it, take it apart, etc.? I assume there are parts attached to the backside housing(drive shaft side), so would hate to not have a document handy incase something goes wrong.

Would appreciate it.

Thanks

 

i used RTV on the outside of the t-case in my '84, 'cause it was leaking like five04ever described his.
now i only did this 'cause it was January, and i didn't want to remove it in the driveway @ that time of the year. in the Spring i dropped it and did it the correct way.
since he was looking for a simple quick fix, i offered that to him, and if he cleans it well enough, it will "stick" for a temp fix. but you're 100% correct, the proper way to seal it, is to drop it.

 

Thanks old skool, I may just try your way (temp fix), cause i thought i would be able to just drop the back side of the TC case, clean and re-apply a nice bead of atv to fix, but i guess i need to drop the entire TC. Never had to do this before so appreciate the input. Thanks