Hello everyone,

finally decided to make an account in search of some advice from actual blazer/jimmy owners instead of /r/askamechanic...

About 2 weeks ago I was continuing my fluid changes and did the transfer case. When I pulled the fill plug fluid gushed out... so clearly the input seal is bad.

Well as a result I was 2 quarts shy of fluid in my transmission and after I added that I started noticing a leak under my truck. I had a catalytic converter installed today and the mechanic told me I "have multiple leaks"...

Its leaking from what he called a shift seal (not sure what that is) and from the pan, and I think one more place I cant rememver. He said he was pretty sure they could all be repaired with the transmission still in the truck...

I guess my question is, where did I go wrong? Did all that clean fluid just wash the gunk sealing my tranny away and now its leaking? How much of a risk would using a stop leak product be? I dont know how bad it leaks while driving, but after I park there is only a few drops in the morning, maybe a 2-3" circle of wetness at most. Any advice on these (apparent) mounted repairs?

this spring when I get my summer car out I plan to try and drop either just the transfer case or both trans + TC.

 

Do NOT use the stop leak products in your transmission, while yes they may swell leaking seals and slow up leaks they are hard on all seals and gaskets.Easy explanation is it makes seals a gummy mess leading too excess wear.
However you do need too address the Input seal between the transfer case and transmission as it will keep over filling the transfer case.
Leading too maybe ruining the transmission due to low fluid, if transfer case has vacuum 4wd switch it will fail filling the vacuum system with transmission fluid, Ect.

 

Hmmm... well that sucks. So I'm guessing then stop leak products aren't the kind of thing that would stop "working" once you drain the fluid, once its chemically active theres no stopping it?

how difficult of a change is this "shift shaft seal"? I have a 99 GMC Jimmy SLE 4WD so I'm guessing it is the 4L60 but I'm not sure (?).