71 Auto Shift problem
Thread Starter
2nd Gear
Joined: Jun 2011
Posts: 2
Likes: 0
71 Auto Shift problem
I have a 71 small block w/ auto in AZ. Do not drive much (67K miles). I took it out today and it would not shift to 3rd without excellerating hard then slammed into gear. Once in 3rd it will not excellerate without excessive gas. It was down 1pint in fluid which I topped off but no change. Help.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Check the vacuum modulator on the transmission. The down pipe from the intake manifold could have come loose at the manifold fitting or at the modulator. If vacuum is getting down to it OK, pull the hose off the modulator and check for tranny oil in the hose. The modulator could have failed, also. Classic symptoms of a vacuum modulator problem.
You can get replacements at any auto parts store for around $20. They don't look the same as the original 'can', but they work OK.
You can get replacements at any auto parts store for around $20. They don't look the same as the original 'can', but they work OK.
