Transmission late shift from 1st to 2nd

[N_tater]

2000 explorer
4wd automatic
So the explorer had been driving ok. A week or so ago I had made note that it seems to do a little bit if late shifting in the later gears but nothing that I was worrying about. Yesterday I went out for the day went 2 town over and no issues. I stopped at walmart when I got home and as I left I noticed that from 1st to 2nd gear it was slipping really bad. Instead of shifting at around 1000 where it had been it was going up over 1500. Once I'm up past that though the rest shift ok. I checked the tranny fluid and it was up to level but it looked pretty dirty. I'm hoping that a fluid change and filter change will help limp it along a little longer. Ive been advised not to do an actual flush. What do y'all think? Thanks in advance. I appreciate your time and help.

 

[Indispensable Explorer]

I got a flush 6000 miles ago when my tranny started slipping in overdrive, it has not slipped since. I'm just one example and I have not driven much since, so don't take my word as scripture. I heard how flushes can be bad after I did it, and I probably wouldn't take the risk again.

 

[imp]

@N_tater ".....1st to 2nd gear it was slipping really bad. Instead of shifting at around 1000 where it had been it was going up over 1500."

Slipping really bad usually implies nearly a run-away of engine speed. Was it really slipping, then completing the shift, or might it have been simply nothing more than a good shift delayed for some reason? A "delayed" shift might be caused by nothing more than a slightly heavier call for acceleration than usual. Has this slipping happened more than once? imp

 

[N_tater]

I havent experienced the same thing since that day. It has been shifting more like it was before. I noticed today that the rpm gabe was stuck at 0 as I was accelerating. I revved up just slightly and it jumped up to 1500 which makes me think the rpms I told you originally were wrong. The best way to describe what happened the other day is comparing it to driving a manual. It felt like if I was disengaging the clutch half way for a second or 2 before actually shifting. So I still felt power forward as the rpms went up.