1996 FLD 120 LOUD bang noise at high speeds

1996 FLD 120 with Detroit 60 14l and super 10 transmission

So recently and randomly a loud bang/pop noise started to happen. And it's very loud.
It maybe is popping every 1 second (1 Mississippi). Doesn't happen until higher gears. Truck is running fine, all gears shifting just fine. I don't think it's the motor at all because you'd hear it more consistent with the RPM. Driveshaft is fine and so are the U-joints.

This morning driver calls me and the popping has tripled. So, it that same 1 second count, its pop pop pop. Every second. But only at higher gears.

Clutch issue? Transmission issue?

Oh, and also, the noise only happens when throttle is applied. Let off throttle at high speeds, the noise stops.

 

This is a compeltely different noise from the compressor popping or the dryer
Nothing like that noise at all. And gauges are at the 120, not building any higher.

 

Its not the air compressor lol 100% not it. Air is not building up to much. The compressor is not weak, actually is quick at airing up. Pops at the dryer properly. Gauges at 120psi. Not 150psi. You said that if its building over 150 psi or building slow. Im telling you it doesnt do either or those. So its not the compressor.

 

We checked that already as well. luckily it's not that.

 

Ive got s video juat trying to figure out how to upload it.

 

https://youtube.com/shorts/w9jvs0VMKHk?feature=share

Here is the noise. The video doesn't do the noise justice. It's very loud in person.