94 vaccum modulator repalced now not shifting

[paulha]

I am always glad to share what little I know and thank you. Now on to the cruise control.

 

[arco777]

Now on to the cruise control.

If the cruise does not work, a common failure point is the speed control amplifier module, located behind the glove box. It is easy to replace if you can find a good used one.

 

[Sip]

The vac line runs up to the top of the intake manifold -- there should be a hard line in plain view up there.

Is it possible that your mechanic forgot about, or dropped, the small metal rod that the modulator hits? If this rod is not reinstalled, you can have a lot of trouble shifting. It is easy to misplace it when you pull the old modulator out.

Can you post a picture of this! I have been trying to find this part and can’t.

 

[ChildIdenticant]

Can you post a picture of this! I have been trying to find this part and can’t.

This thread hasn't been fed in a few years and is best left alone to run feral , hopefully to find a webring to join for survival.

But addressing your question,

A4LD Vacuum Modulator Pin length

A few years ago a friend had her vacuum modulator replaced by a "mechanic". The next day she told me it was not shifting right & over revved on the 1-2 shift. I told her I thought he forgot put the pin back in. She took it back & he said the pin was in there & told her she needed a trans...

www.explorerforum.com

With luck and dilligence , it *may be possible to still find it resting on the trans.

 

[transman304]

 

[teel51]

I have tried to search for this exact problem, and I either searching wrong or something because I didn't find anything like it, if someone can point me in the right direction or right thread I would appreciate it.
So, after looking at where the modulator was I opted to have my mechanic do the work. Got the truck back and it has shifting problems, slow to start, high rpms before shifting, downshifts, etc.
I had none of these problems before I had him replace the modulator, it shifted perfectly, used burned a couple of qts a month but shifted just fine. Any thoughts, I am afraid to drive it much and it is all I have. The mechanic said "it shifts hard but it will smooth out" oh really? Also can someone tell me where the vacuum line from the transmission connects up top? Thanks in advance for any and all help.
Paul

I had the EXACT same problem with my ranger.

I bought an aftermarket modulator, not OEM. Company was Pioneer
I put it in and drove it, wont get out of first gear, I then adjusted it to match the old set screw length. Still nothing. Then I wound it all the way out. Still, nothing. Then I adjusted all the way back, still nothing.
After 6 test drives I said **** it, Im getting lunch.

Then I took it out. I took the pintol stem, and put it in both the old and new and I compared them. IT STUCK OUT FARTHER ON THE NEW ONE!!!!!!!
All that work to put in a new modulator that doesnt even work.

Do the same thing I did. If its off, try getting an OEM one.
Hopefully the OEM one will be right.

 

[CDW6212R]

View attachment 329387

Everyone should make a big note of this information. The modulator pin length is critical. The original modulator isn't adjustable, later models aftermarket are. Altering that adjustment makes the shifts firmer, which improves the ability of the trans to last longer.

Smooth shifts are slipping shifts, firmer shifts slip less. Making the pin longer makes the shifts firmer. The A4LD is not made to achieve hard shifts, it will never bark the tires. But if you make it shift as firmly as possible with the modulator and pin length, plus a VB kit, that will help the trans last a lot longer.

 

[flire]

CORRECTION...!!!! WRONG PART #

Correct part #TM54 from Standard.. shifts correct with only 1/2 turn clockwise... Sorry for the other post. The other Modulator from Amazon took a crap... what a pain in the A$$.... All better now

 

[CDW6212R]

I used the ATP FX-219 vacuum modulator adjustable... 1994 ford explorer .. i did 4 complete turns clockwise and she now shifts very smooth.

...

Smooth shifts are slipping shifts, firmer shifts slip less....

Thanks for the part number reference. But don't suggest others should adjust to make their shifts "very smooth."

The more smooth an automatic shifts, the more slippage there is during that one shift. There's a big difference between smooth shifting and harsh shifting. For longevity, the shifts should be made as firm as possible for the driver's preference, as firm as you can live with.

Wear inside a trans is mainly the clutches wearing, smoother shifters wear them faster. The truth is also that most failures come way before the clutches wear out, almost always something goes wrong in the valve body. Then the shift control is poor, and that greatly accelerates the wear of the clutches. But don't set it up to wear anything out too fast, try to make it all last as long as possible.

 

[flire]

CORRECTION...!!!! WRONG PART #

Correct part #TM54 from Standard.. shifts correct with only 1/2 turn clockwise... Sorry for the other post. The other Modulator from Amazon took a crap... what a pain in the A$$.... All better now

 

[flire]

Ok here is an update,, it has been a week and the mechanic has been giving me the run around and not only is it hard on my tranny I am getting tired of the run around. Turns out there is an adjustment on the vacuum modulator! Does anyone have any idea how I go about adjusting the modulator? I am really getting desperate so get this up and going, pleease!!

 

[CDW6212R]

It is a fine line between really smooth shifts and solid but not hard shifting, which most people call firm. I have two 98 Explorers with the 4R70W's in original condition, not VB upgrades etc. The shifts are smooth, but as much shifting as I have every day at work, they feel a little too smooth to me. I wish I could feel the shift engagement a little more(firmer). Old vehicles with a lot of miles tend to have smoother shifting, up until the point that it becomes too much, too smooth, which is slipping.

 

[flire]

Thanks for the part number reference. But don't suggest others should adjust to make their shifts "very smooth."

The more smooth an automatic shifts, the more slippage there is during that one shift. There's a big difference between smooth shifting and harsh shifting. For longevity, the shifts should be made as firm as possible for the driver's preference, as firm as you can live with.

Wear inside a trans is mainly the clutches wearing, smoother shifters wear them faster. The truth is also that most failures come way before the clutches wear out, almost always something goes wrong in the valve body. Then the shift control is poor, and that greatly accelerates the wear of the clutches. But don't set it up to wear anything out too fast, try to make it all last as long as possible.

Thanks for the part number reference. But don't suggest others should adjust to make their shifts "very smooth."

The more smooth an automatic shifts, the more slippage there is during that one shift. There's a big difference between smooth shifting and harsh shifting. For longevity, the shifts should be made as firm as possible for the driver's preference, as firm as you can live with.

Wear inside a trans is mainly the clutches wearing, smoother shifters wear them faster. The truth is also that most failures come way before the clutches wear out, almost always something goes wrong in the valve body. Then the shift control is poor, and that greatly accelerates the wear of the clutches. But don't set it up to wear anything out too fast, try to make it all last as long as possible.

CORRECTION...!!!! WRONG PART #

Correct part #TM54 from Standard.. shifts correct with only 1/2 turn clockwise... Sorry for the other post. The other Modulator from Amazon took a crap... what a pain in the A$$.... All better now