Baystate Jeepers

I am trying to replace the oil seal at the input shaft of the DANA 300 T-Case. I have this out of the CJ and up on a bench where I can work on it. Since it's out, I decided to replace seals and gaskets.

Following the guide of a Haynes manual, I removed the shaft housing around the input shaft and pulled the housing, input shaft & associated gears out of the T-Case.

I removed the split ring holding the gears to the shaft, removed the gears. I removed the split ring that retains the bearing in the housing.

In theory...the shaft and bearing should be able to be removed from the housing. Mine will release about 1/8", then catch on something firm. It will slide back into position easily. Even a few taps with a plastic mallet on the shaft end and nothing.

What else holds the shaft assy in the housing?

Look way in the bottom . See if the shift fork is holding it. I believe there is a 1/2 bolt hoiding an ideler shaft with a ring to hold the shaft in. It has loose bearings (no cage ) that will have to be greased to hold em in. FjR68

You shouldn't have to remove the input shaft support to change the front seal.

I just resealed mine yesterday. While we did remove the gear cluster (bearings are pressed) there is no need to do so just to replace the seal.

I could not pull the seal from the front with the shaft in place. I even tried to drill a couple of small holes in the face of the seal 'body', and pull with a pick set, pry with a small screwdriver...no go.

So...I pressed out the shaft/bearing assy, then tapped out the seal from the back. It took quite a bit of persuasion. What finally worked was to heat the seal face with a heat gun. There is a green surface treatment to the seal OD which stuck like a son-of-a-gun. But it's out, and the new seal installed in its place. Starting re-assy...except for a home heating oil tank R/R project tomorrow. It's always somethin'...

I guess no one wipes on a coat of RTV on the seal OD, or do you?

Making progress...though pretty slowly.

Doug...are you doing your output shaft seals, too? What are you using for a yoke puller?

rbunch4468 wrote:I guess no one wipes on a coat of RTV on the seal OD, or do you?

Yep, almost always unless the application has a rubberized coating on the mating surface.

rbunch4468 wrote:Doug...are you doing your output shaft seals, too? What are you using for a yoke puller?

No need for a yoke puller, they tap off with a hammer.

We didn't have nearly that much trouble removing the seals. Basically punched a screwdriver through the seal body and pryed the seal out.

Yep...front side yoke removed. Walked it off with a few taps to the yoke body, then repeated 180deg until loose. I want to remove the output housing to replace gasket, shift rod seals, and output shaft seals. Any thing 'scary' to remember, or just pull the ball & tension springs and remove housing from input shaft/shifter rods?

This shift rail seals are above the oil level, are they leaking now? Unless there is an obvious problem I might not do bother. You might be able to use a screwdriver and pry method to replace the shifter seals without having to take a lot of it apart. I have had better luck with RTV to seal the inspection cover on the bottom. JP also did an article on sealing t-cases. http://www.jpmagazine.com/techarticles/ ... index.html

This might help to see how to do the seals you are talking about. It was helpful when I did my 4:1 kit, ignore the sections that do not apply to the work you are trying to do. http://www.jbconversions.com/pdf/2307.pdf

-Andy

rbunch4468 wrote:Yep...front side yoke removed. Walked it off with a few taps to the yoke body, then repeated 180deg until loose. I want to remove the output housing to replace gasket, shift rod seals, and output shaft seals. Any thing 'scary' to remember, or just pull the ball & tension springs and remove housing from input shaft/shifter rods?

We didn't take the shift rods apart. We removed the seals with the rods in place, then installed the new seals.

Yeah, I followed suite this weekend. Input seal replaced, shift rods seals replaced, both yoke seals replaced. Also replaced the bottom cover gasket. Smeared a layer of RTV behind front and rear bearing housings, and re-torqued the cover bolts. I didn't want to further dismantle the transfer case. There are no gaskets installed on mine, even though gaskets came in the seal kit. Front and rear seals on tranny replaced...tranny back in Jeep. Gettin' closer. Tranny R/R turned into a bellhousing repair with threaded inserts. Came out pretty good, though. Ready to add oil to transmission and spin it up before I put the transfer case back in. Cross your fingers.