my wifes 94 explorer with v6 and auto overdrive is sliping or slow shifting between 1st and 2nd. we drove it on sunday then both boys used it. (ages 22 and26) on monday moms fine ride was a little sick. Can someone help with possable problem.

 

Check the fluid level. If it's OK, then the trans iprobably on its way out. The 94 uses the A4LD (LD = Light Duty), not the AOD. The A4LD is a notoriously weak tranny and if you get over 140,000 miles out of it, you're doing good...

 

Here is a link to a site that may help with your 1-2 shift problems.

http://www.misterfixit.com/expltrny.htm

Dialtone

 

You may want to try a tranny flush at your local Quick lube. My '94 started misbehaving at 115,000 and I've managed 240,000 by having the tranny flushed periodically.

 

Dialtone,

I have a 94 XLT 4WD with 75K mi. It just started acting up. It shifts fine 1-2-3-4, very smooth. The problem is when in D and cruising 30-35 mph. When I go up a slight incline in 3, it "BANGs" into 2 tehn Bangs back into 3. Also, when slowing down to a stop it "drags" the motor down more than usual before it shifts back to 1.

I never changed the fluid since the manual doesnt say to.

Could this be the speed governer also?
Thanks
Chris

 

[updated:LAST EDITED ON 15-Sep-02 AT 10:22 PM (EST)]Your problem does not sound like cause is governor related. As I understand it, it is ONLY related to 1-2 upshift and 2-1 downshift.
Your problem sounds more like a torque converter lockup/release issue, or possibly a vacuum modulator issue.
You can try this procedure to disable computer shift functions to see if it helps.

The following procedure will temporarily disable the following transmission shift functions: 3-4 upshift and torque converter lockup.
Disconnect the 3-wire wiring harness at the left side front of the transmission. (Watch out, there are two wiring connectors on the trans. 1 for computer to solenoids and 1 for backup/neutral safety start switch)

Take a normal test drive and verify 1-2-3 up and downshifts are OK. If they are, you probably have an issue with one or both of the computer controlled solenoids in the transmission or signals to pcm affecting pcm related shift point calculations. If the same problem is there, you probably have something sticking in the valve body, or a problem with the vacuum modulator.

Do not forget to reconnect the wiring harness when finished

In either case, you can try the following before taking it in for major trans work. This will not help if the modulator diaphram is leaking however. It will need to be replaced.
Run a quart of trans gum remover such as Trans-X for a while per directions on the can. If it clears your problem up or helps significantly, take it somewhere and have trans pan removed and oil&filter changed. (Oil AND filter)
If it doesn't help, you may as well take it to trans specialist for a look see.
Hope this helps
Dialtone

PS Just remembered another poster with shifting problems. His fix turned out to be throttle position sensor was bad. You could have a bad "Spot" in yours also causing momentary loss of signal to PCM which could cause your symptoms. It is a relatively cheap and easy replacement. Disconnecting the shift solenoid wiring should eliminate pcm shift commands from interfering with the mechanics of the trans shifting in lower gears.
Read your other post and said fluid was brown with no burnt smell. You definately need an oil/filter change.

 

Dialtone,
Thanks for the tips, I ll get on it.

Some more on the my problem investigation.

Again, from a stop, in normal D. The transmission shifts normally 1-2-3.

Something strange happens though. If I hold the accelerator constant, and manually shift from 1-2-D, I can feel shift points from 1-2, 2-3. At about 35 mph, the tach drops again indicating another shift which I thought was a premature shift into OD. Now the even stranger part. When I shift to OD and the car continues to accelerate above 45 mph, it shifts again into OD. Now, add up the shifts. In D, I perceived 4 shifts and in OD an additional shift. It appears I have a 5 speed AOD.
I think Im losing my mind, it "grew" a gear.

Ive isolated the previous problem that I mentioned. In "D" at about 28 mph, if I slightly depress the accelerator the car appears to be in 3 then immediately goes into 4th, the rpms appear to low by the tone of the engine. When I depress harder it will shift hard back into 3. Then back into 4. It will "hunt" between the two gears. The higher gear seems like OD which is too low at this speed. However, that additional shift confuses me.

I feel it is pointing to a vacuum modulator problem. But I am really "miffed" by 4 shift points in D and a 5th in OD.

Please advise.

Thanks

Chris

 

Well, your 4 speed auto did not grow a gear but what you describe sounds like torque converter lock up. I am not sure what speed the pcm issues the signal for lockup , but around 35 MPH sounds about right under light acceleration. The procedure I gave you should let you determine if that is what is happening. It will disable lockup and 3-4 upshift. Disconnect the wiring and see if the hunting goes away. If so then you will need to determine what is causing the hunting problem to occur. Some possible areas to examine that come to mind are:
1. Throttle position sensor function
2. Speedometer input to PCM (sending unit at tailshaft where gear is connected to transmission)
3. Shift lever position input signal to PCM
Keep me posted
Dialtone

 

Its in the shop.. I got my fingers crossed

He has an analyzer. He is looking at the signals and the codes (are there specific codes that will define "health" of these signals from the PCM to the solenoids. Will it detect a modulator issue?) I explained it as an issue with torque converter lockup.

I need to be able to separate the fly $#@$@ from the pepper when he calls.

He is also doing a tune up (fluid,filter, adjust)

Thanks
Chris

 

Well,
The verdict is in.

The mechanic did a diagnostic check on the tranny. Everything checked out. He said he drove the car and he said the transmission seemed OK although he did observe the symptoms I described. He also noted that the engine seemed underpowered. I was skeptical. When he put it up on the lift to change the fluid and filter he noticed one of the sparkplug wires was not connected. He reconnected it and changed the fluid. The fluid and filter look good, no chips.

I picked it up today and it is good as new. Problem gone. It must have been the engine. The strange thing though is that I did not sense any rough running as would be indicated by a missing cylinder on a V-6.

Well anyway, I got away easy ($120) and I have fresh fluid and filter.

By the way, he said that the fluid should be changed annually. That seems a bit excessive. Other than that I am happy with the "honesty" of the place I went to. Heres a plug : Dr. Nicks Transmissions, Milford, CT

Thanks for all your suggestions. This site is very helpful

Chris

 

 

Thanks guys! I love my 92. At 215K it is just breaking in. On a recent 6 hr drive it started these symptoms. Currently 350 miles away from home and tools, my heart sank.

Now armed with this knowledge, I am off to have the OBD codes read. Hopefully the problem is easily resolved.

Thanks again!!