ManWithAVan

On my 1984 g30, the speedometer always reads 0 and it won't shift out of 1st. I had these issues start concurrently on a test drive. The van has a carbed 350 and freshly rebuilt 700r4. I read that these issues can be connected in vehicles with speed sensors, but my van does not have ABS and is pre-1990 so I don't know what is causing it. I have not checked the TV cable or governor but I assume these parts should be good since my trans was rebuilt.

During the test drive I was behind a motorcycle who said he was going about 35 mph. I am not sure if I was going fast enough for it to shift because the van doesn't have a tach. I drive a newer car (2005) which shifts up one or more gears when you are done accelerating. My friend said the 700r4 in his camaro does not always upshift once he stops accelerating. Is this how the trans is supposed to behave or could there be an issue with it? Also, can the trans and speedo issues be caused by the same thing in pre-ABS vehicles? Due to the age of the van I have concluded it might be two parts failing at once, but I am unsure how likely this is.

hanky

Your vehicle may have more than one problem.

I believe the speedo has a cable to the speedo head in the dash. That cable is driven off the gear on the trans output shaft.
If you remove the bolt that holds the speedo drive adapter in the trans , you will need to pull it out , a little "O" ring provides the seal. Sometimes the fiber gear on the drive unit you removed will strip and take off a few teeth. Check for that. If it is cable driven you could connect the cable casing to the adapter and spin the gear . If all is well you should see the speedo needle move. Does It?

William Kisselstein

If you don't adjust the TV cable correctly you will just burn up the rebuilt transmission.

The 700R4 used a conventional cable drive through 1989; check to see if the cable is connected, or if there is a gear on the end of it.