5-ton Exhaust diameter

[TurboMustang370]

The M932A2 I picked up from GL did not have a turn out tip/muffler extension. I'm interested in straight piping the truck just for weekend fun and was wondering if anyone knew off hand the pipe diameter. My truck isn't close and I was going to try to pick up some exhaust piping prior to going back out to it.
I'm pretty sure its either 4" or 4.5" but I didn't want to buy both and return one.
Thanks!

 

[TurboMustang370]

Oh and I checked the TM and used the search function, wasn't able to find the information.

 

[73m819]

The 809s have a 4" exhaust, I straight piped my m819

 

[TurboMustang370]

The 809s have a 4" exhaust, I straight piped my m819

Thank you very much! I greatly appreciate the first hand knowledge/information.