99 full size s-10 blazer
4.3l V6 4x4 auto tranny.

Noticed this problem the other day when driving back home on the freeway. everything was fine, car pulled in front of me and i had to slow down. after dude got out of my way, i went to step on the gass and the tach redlined. had to shift through 3rd, 2nd, and back to 3rd before it felt like my tranny engaged at all. RPMS were at almost 5k in 3rd gear going 45mph.

Same thing happened this morning, i get about 100 yards away from my house and the tranny just disengages. after turning off my car, shifting through the gears several times, i was able to partially find second gear. i was able to gain a little speed going up hill, but if i step on it too much, the tach redlines again.

Any Ideas?

 

Hows the trans fluid level?

 

fluid level appears fine. it's a little darker colored than i'd like it to be, i'm probably going to change the fluid and filter today and see if that helps at all