[updated:LAST EDITED ON 05-Aug-02 AT 03:12 PM (EST)]I have a 76 ford f250 with a 460. I changed it from a manual to an automatic. The c-6 has been rebuilt but when i took it for a test run it didnt have the power that i thought it would and seemed to only shift when it was at high RPM's. I checked the fluid and the fluid was full. I have never had a automatic so is this normal? Or did I put it in wrong?

Any help would be great.
Thanks

 

MODULATOR??

 

Did you buy the tranny used? Perhaps it has a stage II shift kit in it.

Cheers


--Heaven will be inherited by every man who has Ford in his soul--

 

What do i do if it has a stage II shift kit? And what modulator?

 

I think the TRUCKDUDE is right about the vacuum modulator. You will probably have to run a vacuum line to your transmission if you didn't do that when you made the swap.

A C6 uses manifold vaccum to help it shift correctly. I think that's why when you are accelerating in 1st or 2nd, then take your foot off the throttle, it shifts into third.

It's funny, but my truck did the same thing just yesterday. It didn't shift out of first until 3500 rpm and then shifted really hard into second. It wouldn't shift into third under 50 mph. Then when I started to slow down it would shift down into second again. I checked under the hood and I could hear a hissing noise. I finally located an open vacuum fitting, then the hose that was disconnected from it. Put the hose back on the fitting and the trans started shifting properly again. I didn't have time to trace out the lines though. My engine is an '81 351 in a California truck with lots of vacuum plumbing and smog equipment!

I don't presume to know enough about it to tell you how to go about hooking it all up. But our experiences are so similar that it might be the reason your trans is not shifting right.

 

sounds just like my truck. I will check the vacuum line.
Thanks.