steveo1985

I just put a new engine in my 73 and my auto th400 tranny was working fine before i did the swap... When I took it for my first test drive after the swap, it did not shift out of 1st and it slipped out of drive. It also does not go into 1st or 2nd.

wzschirnt

First guess would be the transmission cable wasn't re-installed/adjusted correctly. Your desription is a little confusing, but I would check the cable adjustment first. Then, fluid level.

Was the same engine put back in after a rebuild or is it a different one? Was the converter emptied out when the trans was pulled? If so, was the converter refilled before installation?

Good luck.

MelWff

400 doesnt have a cable to my knowledge. I would check the hose going to the vacuum modulator.

larrywalk

steveo1985

the converter was removed but only refilled with about a qt of fluid... could this be a seating issue?

ajrothm

No.,...

Make sure you have good vacuum going to the modulator first...before doing anything else. Make sure you have atleast 10" hg of vacuum at the modulator....Then report back.....

noonie

Check installation of shift cable.
Shifter should match detents in tranny.
If it won't shift out of 1st, then the vacuum hose or modulator valve.

Upshift or downshift?
Downshift wire or solenoid.

Check level fluid hot first.

larrywalk

The torque converter can't be fully filled statically, only dynamically by the trans pump when the engine is running. This will result in the level of fluid dropping by a couple of quarts or more in the trans, so make sure you check the levels while running at idle.

Although you probably have already checked the fluid level, the vacuum signal is most probably missing from the vacuum modulator due to a leak. This causes the trans to raise both the shift rpm and firmness similar to full throttle.

steveo1985

Ok, I think I have two problems, let me explain further, aside from it not shifting in drive(which I agree, feels like the vacuum line is leaking), the actual shiter lever does not "lock" into drive and it does not go past drive to "1" or "2"...

TERRY CLARK

Does it shift manually ?

JimT

Check the shift cable and bracket. Did you put the bracket AND any spacers back correctly?Did the cable routing change? The shift cable has to be reconnected correctly or some adjustments will have to be made..

427Hotrod

Did you try to start it with a loose or missing ground cable? If so the shift cable usually becomes the ground path and will weld itself internally and not move much.

JIM

JimT

Verify that the detente relay power source is connected! There is a plug/connector on the drivers side adjacent to the shift cable and bracket that provides a connection for the power source. Sounds like that wiring is not connected.

wzschirnt

Hmmm... what's this?

http://www.zip-corvette.com/ProductDetails/ProductDetails.aspx?pid={d2d18850-015a-4798-9024-c48b19f49459}&gid={855ecadb-080b-466c-9127-3a0ec34ebe36}&GroupName=Transmission+Con trol+Cable&pname=68-82+Auto+Transmission+Shifter+Control+Cab le&Referer=&Alias=&ptct=GL1-SR&CTitle=&

Modulator will cause problems also, but it will shift even if the modulator has issues, just really rough shifts. The governor may also have problems.

Anyway, I wouldn't drive the car much if the shifter isn't adjusted correctly; it will burn up stuff inside if in 2 gears at the same time.

Good luck.
walt z.

steveo1985

Thanks for all of your help!! Finally I was able to check the shift cable....Guess what, it was bent!!! This members of this forum are so knowledgable, Thanks again!