Transmission Lag
 

2005 F150 RWD appx 42,000 miles
I have started to notice a lag time when going from reverse to drive. Most significant when I leave in the morning (7am) to take my son to school. My driveway approach does have a slight incline to it and the last few mornings have been colder (16degrees/Michigan) and the lag time was around 20sec. Prior to the colder morning it was 10sec or so. It has been doing this for about 3 weeks or so.

Transmission fluid has never been changed.

Should I do a flush first or have the pan dropped and check the filter first???

TIA

Make sure your trans fluid level is correct, too much or too little will cause transmission issues. Check it several times wiping the fluid off each time and checking both sides of the stick, Do not overfill.
If your fluid level is correct then I believe you have a valve body issue and unless you want to dive into this, a trans shop is your best bet. Call around and see if you can find one that will do a valve body inspection/repair. You likely have a solenoid problem ranging from worn seals to displaced snap ring. My off the wall guess for this repair/upgrade is $200 to $400 plus parts (another $150 - $250) and that would include filter and 5-6 qts of trans fluid. Most shops will offer you a rebuilt trans and won't be interested any internal inspection. Call around prices vary significantly.

This website will give you more detail as to what is involved. My guess is that your issue can be resolved with repairs/upgrades to the valve body and does not require that the transmission be removed.
Transmissionbench.com

Take a look at today's posting, it may give you a path forward
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