I'm a Toyota tech by occupation and a couple days ago traded my 98 vw jetta for a 98 Blazer 160k miles. Truck is in very good condition and so far I'm content with the trade. Brought the Blazer in the shop today, got it up on the lift and proceeded to do a fluid change. Oil, both diffs, transfer case, tranny. Everything went perfect, except for the transfer case. Pulled the top fill plug and out came at least two qts of atf. Completely in shock I immediately hit the Web and in no time, thanks to you guys on here, found that the rear output shaft seal is a very common problem. I topped off the T-case, and threw in a bottle of Lucas tranny fix when I filled the tranny. On my next day off I'm ripping the transfer case off and replacing the seal. Now here's my only remaining dilemma; there seems to be a great deal of confusion concerning whether it's a transmission output shaft seal, or a transfer case input(inner) shaft seal. ANY help in pointing me in the right direction as to the right and correct seal that I need would be much appreciated. Really don't wanna have the T-case off and come to see I've got the wrong seal. Thanks for all your help up until now, guys! So awesome to see these groups of hardcores!

 

To replace the seal between the tcase and the tail shaft of the tranny the Tcase has to come down... Id change both while your in there... DO the job once and youll never have to pull it off again unless the seals screw up again. But thats doubtful If the job is done correctly.

Changing both is just my opinion. Thats what I would do.

 

Yup, just replace em both since you will be in there anyways. They wont be any more than ten bucks a pop. If ATF got in, then the output shaft seal is bad for sure. Theres alot of pressure in an auto trans, and it wrecked the tcase input seal pushing the oil into it. Dont forget the gasket that goes between the 2 as well. If you have a hoist and air tools, I bet you are done the job on your lunch break.

Edit, read it again, looks like you are looking for part numbers... we all seem to like www.rockauto.com for the parts cataloug, go check it out for part numbers.

 

Hey, the quick responses are much appreciated! Thank you guys so much! I can't tell you how cool it is to talk to people that know what they're talking about! Ever have a question about a 'yota, lemme know! Very fortunate, being in the occupation I do have access to a lift, air, and my favorite.. My tools! Thanks again for all help, gentlemen! Real quick, just to confirm my search criteria, I want a trans output shaft seal, AND a t-case input shaft seal? I figured they'd use one seal to serve both but apparently not.

 

Aren't the two seals back to back one facing towards the tranny & other the T-Case? Both are in the front of the T-Case?

 

i would do both....same amount of work in the end. if you change one and its the other, you have to do it all again. just make sure that you put the right stuff back in the t-case. mine takes ATF, i would rather it take gear oil, but i just keep with what it was designed to work with.

 

Yeah mine atf also. DexronIII. Had a guy from a gm dealership parts dept tell me that I needed Autotrac fluid and would hafta come in. Did some minimal research and found that only the 4-button 4wd systems (auto 4wd) need that autotrac fluid and 3 button systems use only dexronIII. Hey, can't blame the guy for trying lol. So it had yet to be confirmed, by anyone I've talked to, and anywhere I've looked to buy the seals, exactly what seals I want. I really need exact names for proper search and purchase. Am I correct in assuming, trans output shaft seal, and tcase input shaft seal? Having a hard time locating a tcase seal with that name. There's tons of different seals. A quick pointer to help me determine which 2 seals I need would make my day! Thanks a ton, gentlemen!

 

i have done this before:
i never buy anything from the dealer. but what i have done; on my 1989 S-15 pickup, is go to the dealer and have them do all the leg work. tell them what you need and that you want to buy the part. the part number could have changed. so what you wanna do is have them look it up and then ask them to write down the part numbers for the 2 seals and then you can look them up when you get home. i had to a headlight switch bezel for my pick up and the number had changed. got the new number from the dealer and bought the part off of rockauto.com for like 10 bucks. waaaaaaaay cheaper than the dealer. so in short, let the dealer do the leg work for the part and get the numbers, then buy them off the internet.
good luck
-Jake

 

Thank you Jake! Very wise thought on this. I'll check with them and go from there. I usually ebay motors for all my parts, but sometimes even they're not too reliable. I'm having an absolute blast nursing this Blazer back to health!

 

use rockauto.com They have great prices I normally shop around 1st then go with the cheapest price.

Rock auto also has a 5 % discount on the forum. It can be found using the search feature.