904 Automatic is Leaking: Advice Needed

[Road_Runner]

While I had the 73 Barracuda up on the lift putting tires & wheels on it last weekend I had a chance to give it a good once-over and the only issue I could find was that the 904 transmission was leaking a good bit.  Typical leak, it had blown the fluid around so it was hard to see exactly where all it was leaking but it looked like it definitely was leaking around the pan and out the back seal.  I'm going to pick up a Mopar Performance deep pan with drain plug (can't believe Chrysler didn't put these in stock!!) so that should take care of the pan, but I've never pulled & re-installed a rear seal where the drive shaft slides in.  Is this something fairly easy to do with the car on jack stands?  Any special pullers or installation tools needed?   I'm trying to do all the work on this thing I can, but I'm not anxious to take the old tranny fluid bath swapping out the pan if I can't fix all the leaks at once.

thanks in advance, Jim

[72rtchallenger]

rear seal is easy to change,,getting it out ,pry it out just be careful an slow,putting it back in just use a rubber mallet and keep it straight,once it starts tap evenly around the seal,,should tap in easily just take your time and dont hit to hard,,its not thick,1/4" or so at base,,something the same diameter of the outer seal can be used to tap it in,,such as a socket,,and with a deeper pan make sure you add enough fluid

[Road_Runner]

rear seal is easy to change,,getting it out ,pry it out just be careful an slow,putting it back in just use a rubber mallet and keep it straight,once it starts tap evenly around the seal,,should tap in easily just take your time and dont hit to hard,,its not thick,1/4" or so at base,,something the same diameter of the outer seal can be used to tap it in,,such as a socket,,and with a deeper pan make sure you add enough fluid

That's great news, thanks.

[71chally416]

Might wanna put a new O-ring on the dipstick tube while you have the pan off. They are notorius for leaking and making it appear to be the pan gasket

[72rtchallenger]

Might wanna put a new O-ring on the dipstick tube while you have the pan off. They are notorius for leaking and making it appear to be the pan gasket

[Road_Runner]

Might wanna put a new O-ring on the dipstick tube while you have the pan off. They are notorius for leaking and making it appear to be the pan gasket

That's good advice, I'm looking at a kit that includes all the seals for the 904 and will be sure to change the tube O-ring, too.  It doesn't look like its leaking from the front seal so hopefully that won't require replacing at least for now.

Thanks, Jim

[tactransman]

Before you remove your driveshaft,wiggle the yoke inside the rear seal/bushing. If it has a bunch of movement,you might need to replace the bushing that is right in front of the rear seal as well.(not an easy job).

[Road_Runner]

Before you remove your driveshaft,wiggle the yoke inside the rear seal/bushing. If it has a bunch of movement,you might need to replace the bushing that is right in front of the rear seal as well.(not an easy job).

Will do, thanks.  Depending on what I find I might take it to a local shop to fix.  Too bad I'm not local to you, based on the opinions here you'd be the guy I'd take my car to for transmision work!

Thanks again, Jim