OldRedMack

Do you have a power wire going to a trailer connection that has a bare spot and is shorting out and tripping the breaker on the firewall when you hit a bump. Had that happen to me before.

Good chance you have a weak eup, that happened with me and new injectors. 1 eup wasn't strong enough for the new injectors, replaced it and all was good.

I chucked mine in the scrap bin. Use the old style and get an s400 turbo.

Only took about 2psi to find my blown gasket on the manifold, It doesn't take much. The key for me atleast is that it is quiet while you are doing it so you can hear the leaks.

Did you pressure test just the intercooler? Or the whole intake? Need to pressure check the whole system. I take the air inlet pipe off of the turbo and pressurize the whole system, just bump the engine over till the valves close and it won't take much psi to find a leak.

Check your fuel filter stand for cracks, took us 2 years to find that problem on a truck.

If alignment and tires don't cure, might be a bad wheel that is out of round or you might need new spring packs. I've never really noticed any difference with new shocks compared to worn shocks. Also check the motor mounts, they normally make more of a banging sound when they are worn, but if they are shot possibility that it could perpetuate the bouncing. That was a lot of words to say in my experience a speed related bounce has almost always been tire and wheel related.

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.