Transmission not shifting properly

1995 MERCURY MYSTIQUE
131,000 MILES • 2.5L • V6 • 2WD • AUTOMATIC
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QFONG
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The car has been sitting for 4 years with old fluid in the transmission. It will only occasionally shift into reverse and when put in drive, wants to start off in 3rd gear but sometimes will downshift into first. Do you think if I change the trans oil that will solve the problem?
Jan 23, 2021 at 1:21 PM
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ASEMASTER6371
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Good morning,

I would change the fluid. After 4 years the fluid is no good. It has separated. That contaminated fluid may have damaged the valves in the valve body as well.

That is the best starting point. You may have to do it several times to see if the valves free up.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

https://www.2carpros.com/articles/automatic-transmission-problems

Roy

NO REVERSE
1. Powertrain control system electrical inputs and outputs, wiring harnesses, Powertrain Control Module (PCM), shift solenoid No. 1, and transmission range sensor.
2. External or internal shift linkage damaged or out of adjustment.
3. Low hydraulic line pressure.
4. Faulty main control valve body.
5. Oil pump assembly damaged or leaking
6. Worn or damaged reverse clutch assembly.
7. Worn or damaged low/reverse clutch assembly.
8. Reverse seal rings damaged or improperly assembled in forward/coast/direct clutch cylinder.
9. Transaxle case leaking fluid
10. Damaged reverse/overdrive gear set.

DELAYED OR SOFT ENGAGEMENT
1. Transaxle fluid level low or contaminated.
2. External or internal shift linkage damaged or out of adjustment.
3. Low hydraulic line pressure.
4. Oil pump assembly damaged or leaking.
5. Fluid filter and seal assembly damaged or plugged.
6. Faulty main control valve body.
7. Damaged low/reverse clutch assembly.
8. Damaged reverse clutch assembly.
9. Damaged forward clutch assembly.
10. Reverse seal rings damaged or improperly assembled in forward/coast/direct clutch cylinder.


Ford does not provide a procedure to service the transmission filter separately from the transmission overhaul. For location of the filter - refer to Automatic Transmission/Service and Repair/Disassembly. The filter is referred to near step 40.
Jan 24, 2021 at 6:45 AM
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QFONG
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I ordered a case of Mercon 5 and will change the transmission oil in a couple of days.
Jan 24, 2021 at 5:01 PM
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ASEMASTER6371
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Sounds like a plan.

Keep us updated.

Roy
Jan 24, 2021 at 5:03 PM