Trouble downshifting from 4-3

[Tigerspark]

Howdy there, I've been using this site for awhile to diagnose my Explorer and finally find myself needing to ask my own question.

For the last few months my 1992 Explorer 4x4 XLT has been having a hard time downshifting from 4th to 3rd gear while at cruising speed (45-55mph) Although it will shift if I stomp on the gas or completely take my foot off the pedal and then casually press down on the pedal again.

I am concerned because she used to shift quite smoothly while just casually pressing a little harder on the pedal while at cruising speeds and now she kindof jolts when I do. It's almost like she wants to shift but something isn't letting her. I first noticed it while the cruise control was on while driving on the freeway going up a steep hill. Like I said before it was a kindof jolting that was pretty unnerving.

I have not taken the pan off yet and looked at the tranny at all. I have reset the kickdown cable.
I am changing the fluid and filter asap and see if that helps.

The only reason I am posting this is because after weeks of searching the site there was nothing that was quite like this that I could find.

Thanks guys.

 

[arco777]

Welcome to the forum!

Hopefully the fluid and filter change helps. Often the valves in the valve body (and the solenoids) get jammed up with gunk. The aluminum body and valves wear in interesting ways and without regular fluid maintenance can stick.

I would start with changing the fluid and filter. If that does not solve your issue you may want to look at doing a valve body rebuild, using a shift correction kit. These correction kits correct lots of problems like this and change out many of the stock springs which may have gotten soft. In some cases "helper" springs are added as well. The parts are not very expensive and the work is not hard, just takes some time and a torque wrench. If you are careful it is a fun job. Good time to change solenoids out for fresh ones too. Adding the correction kit will help shift performance and transmission longevity, and with additional cooling from adding an auxiliary cooler the A4LD can be a fairly reliable trans.

 

[FR-425]

What I think he's describing is not a 4-3 shift but TCC not disengaging on throttle up.

Since he is above 45 mph the TCC is locked.

The exciting shift is when the hydrolic override kicks in at WOT and it drops to 3rd and the TCC disegages at the same time. It's skipping all the way to 3rd because it's being mechanically shifted by the kick down cable.

Mine has done this for the last three years.

The TCC is supposed to unlock at a certain percentage of throttle or a fast throttle movement when the condition of speed i.e. 45 mph has been reached.

When at 45 and above if you touch the brake pedal TCC should disengage, and mine does.

When at 45 or above if you suddenly take your foot off the gas TCC should disengage, and mine does.

When at 45 or above and you suddenly throttle up the TCC should disengage, MINE DOES NOT.

I believe Tigerspark is having this same issue.

Since I am already waiting on my new hot rod trans from PATC I have not done anything about it.

Except to cheat a little....all I did was to go through the kick down cable adjustment properly and then go back and pull the adjuster out 1 notch.

This gives me a mechanical downshift at lower throttle so it's more manageable.

If I really need to go to WOT I give the brake a tap and mash it to the floor.

Not exactly transmission repair but it gets me by.

I don't believe the TPS could be bad to the point that the PCM is not detecting the sudden throttle movement and not throw a CEL but I suppose it is possible.

Might be worth a try. And so I will, er, uh, on payday