stalling question
 

I just got my truck back from getting the heads done. Now everytime I put it in reverse it dies, any ideas? its a 99 f250 superduty with a 5.4

Sounds like either a vacuum leak or the IAC isn't working.

even if its fine in drive?

HMMM, it only does it in reverse. Unless a bare wire or something is hitting when the motor torques to the left when it goes into reverse. Other than that, a tranny problem is the only other possibility.

i double checked everything and in D N and P its fine but in R 2 and 1 it boggs down then stalls

Does it drive normally otherwise?

yes it drives fine

Check the wiring going down to the gear position switch on the side of the tranny. Make sure it isn't hitting the exhaust or anything.