trans problem no overdrive auto
Thread Starter
Intermediate
Joined: Jan 2013
Posts: 33
Likes: 12
From: goodyear az
trans problem no overdrive auto
I changed my battery on an 89 C-4 Auto trans. After that my trans would not shift into overdrive. It used to be 18/19 RPM at highway speed, now 3100 RPM. I did try disconnecting neg cable for 10/15 seconds, as someone suggested it would reset the ECM
Le Mans Master
Joined: Feb 2005
Posts: 6,485
Likes: 566
From: Clearwater Florida
..... Your trans is NOT controlled by the ECM with the minor exception of the torque converter lock-up point … shifting is internally mechanically controlled …..
Melting Slicks
Joined: Feb 2003
Posts: 2,685
Likes: 814
From: Saskatoon Sask.
