Pirate 4x4 banner

1 - 4 of 4 Posts

·
Registered
Joined
·
938 Posts
Discussion Starter #1
Hi all,

My turbo 400 will shift fine from 1-2 but will not shift 2-3. Reverse feels good but just finished the swap so no reference to compare to.

What I have tried so far: new modulator valve line, also measure vacuum on line from lq4. 17 in lbs. I don't think it is collapsing under vacuum.

Adjusted modulator shift screw a couple of turns more aggressive

Pulled vacuum modulator valve and checked vacuum, it does not leak air when out or fluid when in

Pulled modulator valve to inspect for damage, burrs or sticking. It required a little pull to get out, not crazy though. It looks good.

Re-installed, topped off fluid and test drove. Still no shift from 2-3. Also made sure pan gasket was not blocking full seat of vacuum modulator.

Ideas where to check next? Governor weights?

This is a freshly rebuilt trans btw. Some outfit in northeast and I am in South Alabama.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 

·
Registered
Joined
·
182 Posts
My guess is any shop or experienced trans guy is going to tell you to figure out your line pressure. This will at least allow you to have more info when figuring it out. Get your hands on a 300psi (or more) gauge and rig up a way to monitor it while shifting.

Good luck. Trans problems suck.

Transmission Line Pressure - TCI® Auto
 

·
Registered
Joined
·
938 Posts
Discussion Starter #4
I figured this out a few months back and forgot to update the thread. It ended up being the governor, I guess the weights were sticky from sitting dry during the build.

Prior to this I checked and changed the vacuum modulator line. I thought the 1st one was a little soft and may have been collapsing under vacuum. Pressure from the 6.0 was good.

Then I pulled the modulator valve to see if it was sticking on a detent or something. It was difficult to pull out but did not correct my shift problem upon reinstall.

The following weekend I tried the governor and that did the trick.
 
1 - 4 of 4 Posts
Top