Rear pinion Seal and 5 speed Transmission output seal removal and replacement

Saw a couple threads back in the day with people asking about the difficulty and how its done in sort of a walkthrough manor. Allthough its not as hard as you think, id say all you really need do this is to know how to operate a ratchet and an impact gun. I thought id post up pictures but most haynes manuals/ etc cover that fully and im just going to clear up everything in nice steps in the simplest way possible avoiding any terminology except the basic

1. Get the car in the air so you can work comfortable underneath it. If you dont have access to a lift, put a jackstand on each corner.

2. Unbolt the exhaust from the factory exhaust manifold/ Header should you have one and drop it out carefully working your way back from the front of the car all the way back so its easier to get the factory rubber Rings off the hangers on the mufflers making sure your keeping track of all bolts. Also remove the skid panelling thats as flimsy as paper.

3.Driveshaft removal time, its nice and easy to get off once the exhaust is out of the way. Stick the car in neutral so you can turn the driveshaft and begin by unbolting the four bolts on the rear connecting the driveshaft to the differential. Once those are all out, slide the end of the driveshaft facing the rear of the car down, and then carefully pull out the transmission end. For you non messy people make sure you stick a bucket underneath the transmission end as you will get some nice fluid comming out. Inspect that nice smooth end of the driveshaft that came out of the transmission also and take some fine sand paper and lightly sand out any big scratches. Then set it aside out of your way.

4. On the transmission side you will see the seal, there is approx a 1/16" lip on the outside of it that you can get underneath carefully with a fine pick and a hammer, just becarefull not to break anything or using the transmission output shaft as leverage on it. Once you get a lip of it out keep working your way around the seal until she comes out nicely. Once that is done take the new seal and spread some gear oil around it then find some 2" piping you can set on the outside of the metallic part of the seal and carefully tap it back into place with a hammer until its flush with the surface.

5.Now onto the Pinion seal, Note the number of threads sticking out infront of the 1" nut holding the plate on, in my case it was 3 all the way around, and scribe a line going down the nut onto the plate before you break it lose just so that if you dont have a torque wrench to measure how much force it takes to break it loose, you can still get it back to how it was. After thats done pull the bolt and plate off and you will see the pinion seal (i had a pain in the *** trying to find a replacement for this sucker, even mazda gave me trouble). I used some dental hooks to get it out, but any smaller hook will work.Spread some gear oil on the seal once again and once thats out place the new seal in using that piece of metal so you can tap the metal and it hits the seal in evenly.

6. Once thats done you can start putting stuff back together, hopefully you find all your bolts and that otherwise take a look in your manual and buy some new ones or make a run to the local wreckers for some replacements Shudnt be really too hard because once youve got the car all apart its not hard to put back, just remember to maintain match the scribed line and the threads when putting bolts back on and slowly go from their.

 

Tools needed
-----------------
Ratchet set with 10mm,12mm, 14mm sockets and drive extentions
Impact wrench to break loose some bolts if your lazy
Some 80w gear oil if i recall correctly, how much depends on how much you lose out of your Differential and your transmission. If im not right someone correct me.
1" impact socket with drive extension
Can of WD-40 for those tough bolts
Maybe more, still trying to remember what all i used

 

I just did this earlier in the week.

However, I did not know about marking anything or measuring the pinion pre-load. I actually used the air impact gun to put the main bolt back on.

Now I'm affraid that I've screwed my differential up.

What should I do? Can I get back in there and reset the preload after I've tightened it so much?

Anyone selling a S4 TII differential?

Thanks for the help.

Garret

 

Bringing this back up from the dead.

I need to change this seal.....I have a few questions.
- I know I had to mark the driveshaft in relation to the flange when I removed it. Is there anything I need to mark for alignment before I take the front flange off the diff?

- Is there a better way to reassemble everything without counting the threads before you take the nut off. If I understand correctly you can really mess up your diff if you under or overtighten this 1" bolt.

- has anyone else done this with the diff in the car that can add more detail?


THANKS!