Why does my transmission do this?

[BTR]

2000 Explorer XLT 4-Door 2WD 140,000 miles. Original transmission - 5-speed automatic O/D transmission (Ford 5R55E).

When slowly driving around a parking lot (making turns up-and-down the parking aisles), sometimes --- typically when coming out of a turn and starting to accelerate --- the transmission will not "catch." This causes the engine to rev freely and there's no acceleration... the engine isn't "coupled" to the transmission. If I let off the gas and give it a second or two, then the transmission "catches" and everything is normal. What causes the transmission to do this?

Thanks for your help.

 

[JK080]

Low fluid.

Check transmission fluid with engine running in park on level ground at operating temperature.

 

[BTR]

Low fluid.

Check transmission fluid with engine running in park on level ground at operating temperature.

I check the fluid level regularly... per your instructions, it's always in the hatched area of the dipstick... never had to add any fluid... never had any leaks.

 

[JK080]

Falling out of gear around corners is a classic example of low fluid so if your sure the level is correct you may have a problem with the filter. Either overfill it by a quart and see if the problem goes away or pull the pan and inspect the filter and its o rings.

 

[BTR]

@JK080 - Thanks. I'll give that a try and report back.

 

[974X4BLACKSPORT]

If you checked the fluid and it appears full, the next thing to do is put a 0-300 psi gauge on the pressure hydraulic test port and check to see if the pressure is stable in all driving conditions conditions.