I have changed the gears in my rear end housing on my 1969 Plymouth 8 3/4" from 3.23 to 3.55. I now have to change the speedometer gear in my 833 4 speed transmission. The transmission is in the car unfortunately, not on the bench.
1. Can anyone give me an idea of the "level of difficulty" I am in for and anything special I need to be aware of?
2. After removing the bolt from the "bracket" or "tang" that presses against the pinion gear adapter, does the adapter and speedometer pinion gear just pull out?
3. When I am ready to reinstall, do I slide the pinion gear shaft into the adapter and then install everything back in place in the transmission as one unit or do I install the speedometer gear in the transmission first and slide the adapter over the speedometer pinion shaft and press everything into place?
4. Should I replace the adapter pinion shaft seal even if it is not leaking?

I appreciate any help or advice from those "out there" that have done this before. Thank you.

1. Not difficult to do at all.....at least on a 727.

2. Yes it pulls straight out but it is tight sometimes. I've re-threaded the speedo cable back on and used the cable nut as a better hand hold to pull. Have a catch pan ready because there should be some trans oil coming out...at least this happens on an auto with fluid in it .

3. I always install it into the outer cover and put it back as a complete assembly. Be sure to put it in the correct position for the speedo gear tooth count!

4. If it's not leaking, no. Can't hurt if you have a new one but I wouldn't replace it if its not leaking.

MikeR

Thanks for the response...probably not any different on a 4 speed but since I have a 4 speed tranny if anyone else has replaced the speedometer gear on a 4 speed I would really like you to answer the same questions "A12" did.

It is the same set-up on an a-833 .....I would recomend jacking the rear of the car up,this will move most of the gear oil to the front and you wont lose as much if any.

Thanks for the info 1hot68!