Okay the truck is shutting off in reverse, it only used to do it when you locked the steering wheel to one side. Then it started to do it even when going straight in reverse. Now it rough idles when you put it in drive. Put it in neutral and it works like a charm.

No check engine lights or nothing????

4.0 auto. What can the problem be? I am taking it to a mechanic in the morning but just want to get an idea if anyone has one....

 

unplug the throttle position sensor and see if it stops...could be a torque converter or a pressure concern

 

I tried it out again. At start up there are no issues at all. After driving for a bit (15 mins) and putting it in reverse, it will bog/rough idle and die pretty quick unless i give it alot of throttle. Put it in Drive and the RPMs will go below 500 and will spike to 1000rpm back and forth a few times before dying (Again,,,unless i give it enough throttle to take off. Normal driving with full power when i take off). I put it back in neutral and the idle issue goes away. Idles at about 800-1000 rpm.. Could it be the transmission? Smooth shifting on all gears

 

Maybe the idle air control valve (IAC)? Probably not the trans and an IAC is way cheaper.

 

I had this problem. I changed spark plugs, cleaned iac, and maf sensor and it went away. Not sure which one fixed it.

 

Probably IAC had same issue.