2000 C3500 454 Intake gasket replacement

Hey everyone, been lurking a while, first post. Anyone know if a 2000 C3500 454 has oval or square port intake? Need to replace my gasket and looks like Summit is by far the least expensive to find name-brand gaskets. Thanks!

Oval

welcome man....yup, oval

Thanks fellas! Parts ordered!

I just did the same repair on mine. Make sure to use the grey engine sealant from the dealer if you want it to last. The cheap parts store silicone sealents will dry up, shrink and leak over time. Just ask the parts guy at your local GM dealer for the grey engine sealant he will know what your talking about, I think itsGM part number 88861417.

Thanks Circuitguy!

Hope you're thinking about your injectors and fuel pressure regulator while you're in there, also check the condition of your distributor upper bushing and the drive gear. You've got it torn down all the way past those jobs in order to do lower intake gaskets, so why not. The original injectors suck...

Richard

What is the best option for upgraded injectors? Is there a power and/or economy benefit? Thanks!

The originals (Multec design) are prone to leakage, and after considerable miles the regulator is usually shot, too. Both require removal of the plenum to replace. Bosch part # 0280150973 is a direct-replacement injector that is a different design, supposed to be way more reliable. I think it was brianbgboy that originally mentioned them here on DS. I got them from Five-O Motorsports but they're available numerous places.

I did a write-up on replacing them... " target="_blank

Anyway the symptoms tend to be hard starts, long crank time when warm (usually after sitting a little while, not on immediate re-starts) and puffs out a cloud of unburnt fuel as it stumbles to life. This is because the injectors are leaking down into the cylinder while sitting.

I wouldn't expect more economy, might restore some lost power if the old ones are crapping out. It's the kind of thing you really don't notice happening because it's such a gradual failure until it gets bad enough that it causes starting problems. Mine cranks right up under all conditions now and runs like a top.

Richard

X2.......and very important; make sure that all surfaces are "chemically clean"
Use a solvent which leaves no residue such as lacquer thinner, acetone, or brake cleaner immediately prior to applying the sealant.

Rush.....