ok so suposedly i have an aftermarket header.
my downpipe was a tad leaky and hanger was broke and sitting on crossmemember.

so i bought a new downpipe. didnt come with donut gasket. went to autozone and spent 10 on one for it. didnt fit.
prolly because aftermakert header.

it fit the downpipe though.
after installing anyways. (i had to drive it) it leaks very bad and gives me 02 sensor code. bank 1 sensor 1. terrible idle and bad mpg.
ANDDDJHSIDFHSD it still sits on the crossmember(replaced trans mount same time)

SOOOOOOOOOO. why does it still sit on crossmember? hanger needs bent? the downpipe hangs kinda low.

and what do i do for a donut gasket. no idea what brand header i have.
any DIY donut gasket things?
the outside diameter was fine. inside wasnt. it was too small for header flange.
so i tried grinding it down with dremel. would do a thing.
tried a carbide bit. it ripped the it up since its like an sos pad..

sounds like open downpipe ford f150

cut off header flange and dp flange and just hardmate it together?