alright heres the break down. my alternator went out about 4 days ago my car was running great. so it sat all those days and i replaced the alternator today so i went for a little drive to charge up the battery and make sure the alternator works, well while driving around i was running around 2k rpm's and then when i hit 30 mph it wouldnt shift to third gear but when i coulumn shifted it would go pass 30 but about 35oo rpm's but still wouldnt catch 3rd. i drove back on base shot the car off at the store when i left i babied the hell out of it and now it was starting to shift to third. should i get it checked out, i have 104k miles on it, and just ordered a bunch of performance upgrades dont know if i want to throw them on now if i have to replace the trans but i'm thinkin this may be a good opportunity to switch to the 5 speed finally......... please help me out here thank you.....

 

Sounds like the trans is on its way out. You can try a trans flush to see if that makes a difference, but I doubt it.

 

Sounds like the tranny to me. You have the 4r70w transmission not the AODE. 98-2004 came with the 4r70w. The damage is already done. Don't even waste money flushing it. Get it to a tranny shop.