OldRedMack

GA is 64,000 lb gross on 3 axles, lift axles only mean you can haul less weight in GA. Also even though it's 64k gross, if you have a lift axle on the truck you have to use it. So you get less payload with more wear and tare.

If it took 2 hours of sitting turned off to drop that much then it's not a huge leak and the truck is safe to run. But if it was running and did that then you would have a problem.

Check the filter housing for a Crack, took us 2 years to finally find that on 1 of our trucks.

Don't know how it would effect idle, but the compressor is pulling air out of the intake manifold and has a short hose on each end of the metal pipe that routes behind the engine. One of those could be split and your losing intake pressure until the compressor kicks on and is sucking more air thru the system?

Looks good to me, your just caught between gears at that range. Crusing rpm with my truck is 1650-1750 at about 600.

Good enough answer to order 1. I know it should be as simple as calling mack and giving them my Vin, but I really don't like dealing with mack in Atlanta. Google gave me the part number for a 460 and I gave it to my pai guy, so we will see when it gets here. Getting a new pressure relief valve also. The truck isn't running bad just seems a little lazy, boost is off about 2psi. But the Pyro hasn't changed so I don't feel like I have any intake leaks.

It includes the filter pad, just not sure if they are the same thru all the power ranges or different depending on HP.

Does anyone have the part number for AI fuel pump. I have the 370, is the 460 pump different?

Leave the unit pump wires hooked up and try cracking the injector lines 1 at a time to try and locate. My guess is you have a bad eup and it's not supplying enough fuel for the new injectors.

Also like Jojo said, we had a plastic liner that goes into the top of a pop bottle get drop in a tank, took forever to figure that one out.

Just had a 94 300 mechanical that we chased an air issue for 2 years, and finally found a tiny Crack in the filter housing. Had the filter housing off of it a few times and didn't catch it till the last time. Fires off fast now and runs like a champ.

We have a 2001 350, and when the "chirp" as we call it starts its a matter of time until a new cam.

If your looking to go above the 400, they are probably looking for the 419m3 and 1868 nozzle tips

I would start with the thermostat.