Possible transmission problem with 93 Aerostar

[TallPaul]

Is the tranny on a '93 Aerostar electronic? My '92 has a vacuum modulator to shift gears. I have changed the ATF regularly and at 127,000 mile the tranny works fine.

If his engine is running very poorly the tranny will have to run in lower gear to get down the road. Check tune and power of engine.

OBTW, I would run Redline D4 ATF in it. I first put M1 ATF but then when I learned about Redline I switched over. The Redline will take the heat and that tranny is wedged up in a tight hot place in these Aerostars.

 

[demarpaint]

It has a vacuum modulator, I replaced that about 20,000 miles ago. This brings me to another question now, is the TC electronic with these units that have the VM? If not that saves me some grief, because then all I have to do is ask the mechanic to adjust the bands and see what happens.

It shifts fine, just not as pronounced, I had it on the highway last night, and moved the gear selector from OD to D several times and felt the downshift, and up shift each time as I moved it. What confuses me is it doesn't seem to coast as well when lifting my foot off the gas pedal, a part of me says its nothing but its using more gas than normal......... I used to drive this everyday, now I switch off from 2 other vehicles, one is new the other has a stick shift.

As you can tell I must have cut class when it came to AT 101.

Thanks,
Frank D

 

[TallPaul]

My mechanic said not to adjust the bands as it is tricky and can cause problems. Maybe he is just not confident though.

I would guess most of us have flunked At 101. It is a complex subject.

Again, I wonder if the engine is not running at best power level, which would tend to leave it needing lower gears to move it's mass down the road.

I once induced a tiny air leak in the vacuum modulator line (put a T in the line and used a small fuel filter to make sure I didn't induce dirt. The "leak" line, I stuffed a piece of plastic with a tiny hole down the center into the line. Big leak and won't shift out of first. Tiny leak and will firm up shift.

I later removed my induced leak. As it seems to shift firmer with the Redline D4 ATF.

 

[demarpaint]

You might be onto something, it does need a tune up, I've been holding off until the fall. It seems to be running Ok though. The thing puzzling me is when you take your foot off the gas at lets say 55-60mph, it seems like its in 3rd instead of OD, but shifting the gear selector to D I feel it downshift.

Is the convertor electronic in the 93's, even with the vacuum modulator........Most tranny shops around here are going to drop the pan and try and sell me a rebuilt unit, that's just how they operate. I am hoping my buddy can point me to someone honest if he can't do it.

I will have him check the vacuum modulator for a cracked hose as well.

Thanks again!

Frank D

 

[TallPaul]

My Haynes manual says the Aerostar ran the A4LD tranny through 1986 - 1994. Electronic trannies had an "E" at the beginning. So yours should be simply vacuum modulated. MAybe modulator bad again, though mine has never gone bad.

I highly recommend you check out ford-trucks.com

They have a forum for Aerostar. If you don't want to sign up an account, PM me what you want to ask and I can post it up for you.

 

[demarpaint]

I posted there as well, but no replies. I have a pretty good idea of what to ask my buddy to check. Many Thanks!!!!!!!!!!

Frank D

 

[exranger06]

In 1993 the torque converter lockup and the 3-4 shift are electronically controlled. Everything else is vacuum modulated.

 

[TallPaul]

Originally Posted By: exranger06
In 1993 the torque converter lockup and the 3-4 shift are electronically controlled. Everything else is vacuum modulated.
Good point. May not be electronic transmission, but still have an electronic feaure. This is confirmed by BEControls.com:
Quote:
The A4LD four speed overdrive transmission was introduced in the 1985 Bronco II/Ranger and saw use behind many 4 and 6 cylinder engines until the 1995 model year when it was replaced by the 4R44E and 4R55E electronic transmissions. The A4LD was the first Ford transmission to use an EEC-controlled torque converter lock-up clutch and later became the first to use electronic shift control (via a 3-4 shift solenoid). The French-built A4LD was created by adding overdrive to the front of the C-3 three-speed unit.
from This Page. So it seems a good possibility that the electronic part is the problem.

 

[demarpaint]

Originally Posted By: exranger06
In 1993 the torque converter lockup and the 3-4 shift are electronically controlled. Everything else is vacuum modulated.


As I confessed earlier I probably cut class on trannys 101. Since the TC is electronically controlled what exactly is it not doing if this is in fact is the problem? It appears to be in OD each time I move the shifter out of OD into the D position. But yet when in OD it feels almost like compression braking, although slight when my foot comes off the gas. Does the TC locking up make it more like being in neutral when my foot comes off the gas?

Go easy I am trying to make up the class I missed

Thanks,
Frank D

 

[TallPaul]

Well, let us know how it turns out.

 

[demarpaint]

Will do, thanks for all the replies!

Frank D

 

[demarpaint]

Well I just got back from the mechanic and he said the tranny's good and he wouldn't mess with it. The modulator is working, TC seems to be doing its job, he did the voltmeter test mentioned and no problems there. Shift points are good, OD working, its shifting well, the unit is nice and tight for 162,000 miles.. His recommendation was LEAVE IT ALONE.

I'm puzzled but maybe driving my van with the 5 speed stick and the new Jeep have me going nuts.........I am going to start checking MPG. I still think something is not 100%, but am not going to look for trouble!

Thanks for all the replies,

Frank D

 

[oldmaninsc]

Originally Posted By: demarpaint
Originally Posted By: exranger06
In 1993 the torque converter lockup and the 3-4 shift are electronically controlled. Everything else is vacuum modulated.


As I confessed earlier I probably cut class on trannys 101. Since the TC is electronically controlled what exactly is it not doing if this is in fact is the problem? It appears to be in OD each time I move the shifter out of OD into the D position. But yet when in OD it feels almost like compression braking, although slight when my foot comes off the gas. Does the TC locking up make it more like being in neutral when my foot comes off the gas?

Go easy I am trying to make up the class I missed

Thanks,
Frank D


When the torque converter locks up, it should feel like another shift. You have the 1-2 shift, the 2-3 shift, the 3-4 shift, and then the torque converter locks up. If you had a tach you would see the rpms drop when the t/c locks up.
A simple way to test to see if the torque converter is indeed engaging is at around 50 MPH, keep your foot on the gas pedal, and with your left foot - tap the brake pedal and let off. This will disengage the lockup of the torque converter. You should feel the RPMS increase.
Or another way is to get on a highway/freeway going around 55 or above. Push the gas pedal down slowly until the tranny downshifts. THEN, manual move the gear selector from overdrive to 3. You should feel another downshift. The first shift should have been the torque converter disengaging.

I went through this on my first Aerostar (87) after a rebuilt tranny. My 87 had a tach (digital gauges) and I could see when driving on the highway that my RPMS were much higher than they used to be. The original tranny shop said this was normal and nothing was wrong.
I took it to another one and they showed me these "tricks". In my case I had a bad "computer" is what they diagnosed. After replacing the computer - all was well. I traded the 87 in on my current 95 about 3 months later.
I've had very few problems with the 95,(one 02 sensor and TPS sensor) but had NOTHING BUT PROBLEMS with the 87.

 

[demarpaint]

I'm going to give it a try since I am not 100% sold that nothing is wrong. Talk about looking for trouble . Your test sounds easy enough and not too technical.

I planned on doing an OC tomorrow, and cleaning it so I'll give it a try in the morning. It will be a good excuse to get the oil nice and hot before I change it out.

Thanks!!!!

Frank D

 

[demarpaint]

Everything seems to check out. For an added measure of protection, I flushed out the fluid and replaced it. The filter has less than 20K on it, I plan on dropping the pan and swapping that out in December.

Thanks for all the replies,

Frank D

 

[exranger06]

To see if the torque converter is locking up, leave in Drive (not Overdrive) and accelerate up to ~55 mph. The torque converter should still lock up in third gear, which should be more noticeable.