Operation CHARM: Car repair manuals for everyone.

A/T - AOD Loss of Governor Pressure Through Valve Body

TSB 88-20 (May)

SUBJECT: FORD AOD

PROBLEM: Loss of governor pressure through the valve body.

SOLUTION:
The shift valves in the Ford AOD valve body depend on governor pressure to upshift.

Governor pressure is sealed in the valve body by aluminum plugs held in by a keeper at the edge of the valve body.




An easy way to seal these plugs is with a small tubing cutter. By running a small ridge around the outer diameter of the plug, flair the metal just enough to obtain a snug fit when installed (See Figure 1).

The plugs that should be sealed are for the 1-2, 2-3 and 3-4 shift valve and orifice control valve (Figure 2).

Be sure to check the plug keeper for wear.

A worn keeper will allow the plug to move back and forth, causing plug to lose its snug fit.