sweet

Sorry its taken me so long to reply to everyone, The truck is a manual and no the truck hasnt had a chance to make it to the track yet. The boost guage was fluctuating just hard to tell in the camera due to the reduced quality because the video is online. We did find out though that the boost fluctuation was due to the gauge being faulty. He has since gotten another guage and it is fine. I will have more videos of this truck soon.

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i would think 3.0 if its manual

i would check your engine bay for black dust, it wont be much but look especially around the snout if there is dust then it's belt slippage. check your tensioner i.e. get a smaller belt. If not than you may be running too lean and the computer is pulling too much timing.
as far as over spinning the s/c that should not be the case b/c the s/c company designed the s/c to the engine/ rpm. You could also be running out of fuel..there's several reasons this could be happening but those would be where I'd start.

is that the 4.0 OHV, SOHC, or is that the 3L v6? Do you have any 1/4 ets?

I didn't see the fluctuation that you're talking about, unless you're talking about the beginning of the video? it's normal to flucatuate 1lb of boost in the upper RPMS, if you rev the engine above the S/C spec RPMS, for ex. it makes peak boost (7lbs) at 5000RPMS and you rev it to 5500RPMS then it might make 8Lbs, and can damage the rotors in the S/C.

my car does the same thing. are you using that plastic hose into the back of the gauge if so try a rubber hose that helped me some. it could also be your wastegate

i wanna see some vids of this truck givin er