Can anyone tell me where the modulater valve is on my A4LD tranny. I have a 93' ranger XLT extra cab 2wd with 4.0 engine. I have looked all over the tranny and thought it would be somewhere I could see it. I know I had one on my old full size Ford truck with C6. Thanks

 

on the side of the tranny.

 

I have searched bothsides but can't seem to find it, unless it is on right side crammed next to cayalytic converter. I will look again. Does it have a vacuum hose going to it?. Thanks again

 

I found it, was hoping to be able to get to the adjustment screw but it is a very tight area with a heat shield there also.

 

if there is any fluid in the hose the valve is bad and will need to replaced.

 

I am going to replace it; it is shifting hard and going up in speed before it shifts to the next gear. Think I will remove the passenger seat first to see if I can change it out thru the floorboard rather than pull the exhuast pipe down.

 

Through the floor-board?

 

Rust? Cutting torch? Zip gun?
The symptoms of a bad modulator are 1)won't upshift or late upshift more likely. 2)smoke out the exhaust followed by low fluid level.
Engine intake manifold vacuum is applied to one side of the modulator diaphragm. At idle, vacuum is high, and at cruise, vacuum rises a little. When you step on the gas, vacuum falls, allowing the modulator spring to push against valve body stuff. When you let off the gas, or the engine approaches 'easy work' at higher rpm, the vacuum rises a bit, so the diaphragm gets retracted, letting the valve body move towards 'upshift'. Additionally, the governor is cranking along, increasing its 'force' proportional to the increase in speed, so the modulator has additional forces 'pulling' for the transmission to "upshift as soon as you can, bud". This happens in each gear position, except R, I think.
Generally, once set properly, you never have to mess with a modulator. They work or they don't. If you aren't getting upshifts, check the vacuum connections at the manifold & modulator.
tom