Replacing the Speedometer Pinion Seal

The procedure is simple:

1) Jack up the front of the car and place jackstands in the appropriate manner to support the vehicle.

2) Locate the speedometer pinion gear at the rear passenger side of the transmission.

3) Unbolt the one bolt retaining the speedometer pinion and the bracket retaining the speedometer cable to the frame of the car.

4) Remove the pinion gear sleeve by unscrewing it with your fingers (you may need to break initial torque with some vice-grips or something if the sleeve has been on for 14 yrs.)

5) Pull the speedometer cable out of the pinion gear and try to place it out of the way...be careful not to bend or break the cable (its tough, but just be careful).

6) The pinion gear must be pulled out...it doesn't have threads but the gear inside has teeth that go in at a slant. It may seem at first like the gear doesn't want to come out. You just need to pull it out (you can use pliers or something, but be careful not to strip the threads that the pinion gear sleeve goes onto).

A little gear oil will probably spill out so have something under the car to catch it.

7) Once the gear is pulled out, look at this picture to see what you'll have to do.

First you need to remove the little pin indicated by #2. I punched it out with a nail. I first flattened the end of the nail, otherwise it would just get stuck inside the pin...the pin is a skinny hollow tube. With the hammer I just gave some moderate taps and it came out. Once you have that part out you can pull out the gear...this gives you a better shot at the seal since the gear has a little rod attached that penetrates through the front opening and goes inbetween the seal.

#1 is the old oil seal. It is a metal ring coated with some rubber (plastic) and it is in there pretty tight (hence the mangling). Do what you need to to get it out, but be very careful not to scratch the inside of the metal cylinder while doing so. If you do, then you could end up leaking even more than before. When you get it out, you can just put in the new one...make sure you put it back in in the same orientation. Once you have it back in nice and tight you can put the gear back in and replace the pin. Don't bend the pin when you hammer it back in. You'll also want to replace the O-Ring that is lying up against the pinion gear...it goes in the slot its being held up by...that part is self-explanatory. If your pinion gear is really messed up, replace it.

8) Now put everything back where its supposed to be...this should solve your leaking speedo-cable. Note that the tube may still have an amount of tranny oil still in it...some people have had to drain the cable to solve the problem entirely, which means you have to unattach it from the back of the dash (if applicable...if you have a speed sensor you won't be leaking inside the car). In this case, you may as well replace the speedometer cable in my opinion. Good Luck.