Eddie 70

Follow along closely boys and girls. After putting the engine in my car I drove it to the muffler shop about 20 miles away. Watching all the gauges. Everything was cool. I get my exhuast welded up and come on home. Somewhere along the way my speedo quits working. Well I do a little looking into it and I see my cable is laying against my exhaust pipe. Darn. I go buy a new cable. Install it and expecting it to work, drive off. No speedo. I come home and connect my drill to the cable, at the tranny end, and I can go 70 MPH in the garage. Speedo good, cable good. Must be the little plastic gear. I replace that with another gear I have with the same tooth count. Go for a drive, nothing. What is up here? What could be going on here? I pulled the plastic gear at the tranny one more time and get the car up high and peer into the hole where the plastic gear was. What do I see, NOTHING.

:eek: :banghead:

There is nothing there to drive the plastic gear. What or where did the drive gear go? What am I missing here? Some one point me in the right direction please.

drspeedy

I had the same thing happen- I put in one exactly the same, no dice. I ended up buying a replacement gear to replace the replacement... worked fine. GM dealer had one in stock, too :)

:steering:

-doc

jerryp58

I'm not sure how your 4spd looks, but I couldn't see the speedo drive gear through the driven gear hole in my TH350.

There's always the possibility that the drive gear in the trans is damaged.
On my auto, that wasn't too bad a job, but I had the plastic gear, not the pressed on metal one.

I'd fiddle with the driven gear some more (maybe even get a new one) and make sure that the teeth aren't worn down on it (them) and make sure that it's seated well.

Good Luck.

Jim Martley2

I had a similar situation happen to a buddy's Vette. Turned out that the clip that holds the speedo drive gear on the output shaft of the tranny snapped and the gear moved back on the shaft. This was on a Turbo 350 automatic. A quick trip to the local Chevy dealer for a $2 clip and 3 hours of labor later, the speedo was working like new.

Eddie 70

Jim, this sounds like what may have happened here. I couldn`t feel any gear at all when I was feeling for it. I knew something must have happened.

How do I go about correcting this mishap.


[Modified by Eddie 70, 8:38 PM 1/13/2003]

Jim Martley2

Eddie,
You need to pull the driveshaft, front driveshaft yoke & the rear transmission tail housing. There are 4 or 6 bolts that hold the housing on. The housing will come off without pulling the transmission out of the car. I would also replace the rear seal and the yoke bushing in the tail housing while you had it apart.

Eddie 70

It looks like I have my work cut out for me today. Thanks for the help. I will post the outcome on this one.

Jim Martley2

Eddie,
How did you make out with your speedo problem?

Eddie 70

Jim, you were correct about the gear. I haven`t been working on it that hard. It got too darn cold here for me this weekend and my computer died also. First things first. I had to get me a computer going again. Now I can resume the tranny fix. :hurray:


[Modified by Eddie 70, 8:58 AM 1/21/2003]

Fevre

Same thing happened to my 4 speed, cable on pipe. New cable worked for a while but I am guessing the tranny gear is stripped. No longer an issue, t-5 arriving today! :yesnod: