First off, thanks to all ya'll here on Dodge forumn, I've learned alot about my truck and different mod or repairs that can be done. Now I have a question to ask. What the heck is a Plenum? I first heard bout it on a cat related post and I'm just so dern curious bout what it is. Anybody want to fill me in?

 

Your plenum is a plate bolted under your intake and there is a gasket in between. Dodge had a bad design when they built these trucks. They have an aluminum intake with a steel plate. Look down your throttle body and see if there is oil build up. If there is than your plenum gasket is shot. When you order new gasket get a new aluminum plate. Google search hughes and they have kits.

 

The empty space inside the intake manifold. There is a plate on the bottom of the intake that seals the plenum, but, it was a rather poor design..... and the gasket there blows out. (the bolts are too long.) There is the stickied plenum thread will that will you a lot more than you ever wanted to know about the plenum.

 

SO all ya'll that have the Hughes have had to replace or repair the plenum?

 

Not all. Some have done it to head off problems that haven't happened yet, some have done it because they misdiagnosed a failed PCV valve.