Celica Forums General Discussion Engine and Performance 2000 automatic tranny problem

I bought my car mid April, 185k+ miles on it, but its a Toyota.

It has aftermarket stuff done to it but it drove PERFECT until 4 days ago.

Now mind you I'm dumb when it comes to cars, I know a little but not enough.

Here's the problem.

It shifts perfect from 1st, 2nd but when it gets to 3rd (35-50mph) it does this weird boggy type deal. It'll rev to about 3000rpm and then bog then shift but when I let go of the gas it bogs down gear but revs up again. I don't get it.

It also does hit or miss type deals when going up hills to where it doesn't want to get out of 3rd gear and i can be going 50mph+with out shifting gears. I don't get it and it scares me considering I just loaned 4000 to get the car and I know I got ripped off.

I don't have 1500 dollars to fix this if its in need of a new tranny. I'm scared

Help me.

Toyota HIGHLY recommends their own tranny fluid. Other fluids can lead to shifting problems (so they say).
I would drain and replace the fluid with Toyota fluid and see if that helps.
My $.02
My 2000 shifts perfectly @ 165k mi.