how hard is it to replace rear tranny oil seal

[defektes]

I just noticed a leak coming from my rear transmission where the driveshaft connects to the transmission.

I assume this is the same type of seal as the rear main seal.

How hard is this to replace and what speacialty tools will I need?

thanks in advance

oh look in my comment for the car

its a manual transmission.

 

[pcoxe]

On most rwd cars you disconnect the u-joint at the differential, then pull the driveshaft and yoke assembly out of the transmission. Pry/pull out the old seal and drive in a new one. They make alignment tools to drive them on squarely, but you should be able to tap one in if you take your time to seat it evenly all the way around.

 

[duaneb9729]

i have used an old soup can that was the same size as the seal and used a hammer to drive it in, it worked well the one time i needed to do it

 

[mechtech2]

Clean your yoke shaft where it will ride on the new seal.
Light fine steel wool or Scotchbrite is good.
Then lube it and the seal before you put he driveshaft back in.
The seal can be taken out in a number of ways. Collapse it inwards with a punch, an pry it out. Use a seal remover tool [a little crow bar device]. Drill it and use a dent remover.
Any common sense means. They are not in there with a death lock.
You can tap the new one in evenly with a hammer. Slowly work around, and don't distort it. A large socket can often be used to hit against and drive it in square. Even a flat punch or bolt can be used.
CARE is the key.

 

[paulo57509]

I usually replace the tail shaft bushing along with the seal.

It's not a must-do because it takes a special tool to remove and replace the bushing with the tail shaft housing installed on the transmission.

With the mileage you have, it might be something to consider having done.

Edit:

The bushing pullers look like these:

They're specific to the application. Not worth purchasing unless you have a few bushings to pull. They usually come with the installer which looks like a hollow punch.

 

[Chris142]

Usually the seal leaks because the bushing is worn.

 

[defektes]

Autozone and Kragen don't even carry the bushing for my truck! I'll have to check out NAPA tomorow.

Thanks for the tips!!

 

[defektes]

Is this the bushing you are talking about?


http://shop.oreillyauto.com/productdetai...199&PTSet=A

 

[Chris142]

No the rear out put shaft bushing. It looks like a sleeve, round about 1.5 inches long, brass colored. The driveshaft slides into it.

 

[Chris142]

looks like this.

http://cgi.ebay.com/ebaymotors/Know-Your...sQ5fAccessories

 

[Chris142]

I've never seen a bearing back there. Does your driveshaft slide in and out of the trans or does it bolt directly to it?

 

[paulo57509]

The OP doesn't have a TH350, but here's an exploded view. Reference #66 (lower right). This is the bushing in question.

http://www.automatic-berger.de/Explosionszeichnungen/General Motors/th350.htm

Again, removing and installing this bushing with the housing installed in the trans is impossible to do without special tools because the trans output shaft is in the way. Even if the housing is removed, the bushing is still relatively hard to remove.

 

[defektes]

Thanks for the photo.

So basically I should swap the oil seal and wish for the best then lol.

 

[mechtech2]

Right. Dive into the bushing only if you have to.
Loose/worn/broken engine and trans mounts make rear seals leak more.
So do worn U-joints.
And get the output angle the same as the differential input angle.
Shim the trans mount for this.
If you find the drive shaft yoke is worn too much [ a groove], you can get a Speedy Sleeve that covers it, and it will have a new wear surface. This will come with a recommended seal - it may not be able to use the stock one.

 

[defektes]

I removed the 4 bolts holding the u-joints at the rear of my truck and the differential will not budge at all. Not in any direction.

 

[Chris142]

Does it have a slip yoke where the driveshaft goes into the trans or does it have bolts?

 

[defektes]

I used a crowbar and it finally moved and I removed it.

Now I got to try to figure out how to remove the old oil seal.

Fun Times!

edit:

Mechtech2, the yoke wasn't grooved alot. It had a couple (not very deep,) lines but nothing major.

 

[Chris142]

How is the area where the bushing rides? Smooth or grooved? Does the thing have any slop when installed? Up and down or in circles?

 

[defektes]

Not sure, I had to go to work before I could get the seal out on a emergency call.

I will take some photos of the yoke and the inside the of the tranny after I get the seal out tommorow.