new alternator and still having shifting issues

[Tivs]

so my truck was shifting early into 3rd and slamming into it. i had a bad voltage regulator in my alt. swaped it and the truck shifted better than it ever has, flushed it the same day. drove it all day today and now its acting up again ( did the alt and flush yesterday) its not nearly as bad as before and only did it a few times but still frustrating. if i ease into the throttle it does great. but a few times i got on it it would just bog down in 3rd shifting from 2nd at 2200 rpms hit third and be at 1000 rpms if that. both times i got on the high way shifted smooth through all the gears every gear staying at 2200rpms.

[Tivs]

Cleaned my tps seemed to help. i know my vss is bad would that affect shifting