i have a 97 f250 and in the last 3 days i've gotten this weird combination of symptoms and wanted to see if you all think it could be the cat (which is undeniably in pieces judging from the rattling i hear).
started with an occasional dead spot when taking off. then proceeded to a more definite dead spot while taking off, to the point it almost stalled out, then i got weird rpm fluctuations. at some point while going up a steep long hill i realized my rpm's were hovering around 1500 at 45 mph and i couldn't get the truck to go any faster but then it seemed okay again. and then the tranny started shifting up and down between second and third all on its own. now the weird part is that yesterday i drove it for 20 miles and got NO symptoms except a tiny dead spot at the end of the drive.

the check engine light came on 2 times but it wasn't checked for codes yet. it came on while we were on a flat going about 45-50 mph.

so is it possible that the cat is responsible for all that?

and if it is the cat, those of you who replaced yours, what did you get? i haul with this truck so i'm a little weary of the $50 cats i see out there...

thanks in advance!