90 f150 e4od trans. slipping on 1-2 upshift, especially under hard acelleration, it was a little less after a fluid/filter change with an additive, doesn't seem to slip when manually shifting looking for any ideas on what to try. if i do have to replace, is there any converters with a higher stall speed avable.
second problem it has a low mileage engine using a qt of oil to about 500 mi. this engine has, edelbrock intake, world products winsor heads (i've been told these heads could be cracked, but don't know the deatalis, heads were new out of the box,i've also checked for vac. in the crankcase, it's making a little preasure in the crankcase, normal i think.)headman headers, and some other mods, cam, injectors, etc. also i had to dimple the baffles in the stock valve covers thinking this may cause the pcv valve to cause incorrect vac on crankcase, i've removed and replaced with a breather and have yet to put some miles on it, when pcv was still in place, i had someone driving behind me and they saw lots of smoke under hard acel., need to try again with pcv valve out, anyway i'd likr to hear any ideas or sugestions thanks.

 

I've owned three Ford trucks and all of them used some oil. It sounds as though you have some engine mods; I was looking for some info on intake vs. exhaust and learned how important balancing these are. I heard if they are not balanced, oil usage may result. Mine now has alot of blowby and I end up getting oil in the air cleaner.