I have a gen III, 2004 Avalanche 5.3 (Swapped into 1978 caprice). I'm looking for more information about the redesigned pcv system in the gen IV driver side valve cover that is said to solve some smoke on start up issues. Does anyone have more information on this, and specifically part numbers as I have found different part numbers and I'm not sure which work with a Gen III engine. Also, would I need to modify the coil brackets to fit a newer style, Gen IV valve cover.

Thanks,
Brandon

 

Dorman.

Don't have to modify anything. Bolt up and go.

 

I'm not sure what that means. I know Dorman is a parts supplier. Do they offer an aftermarket valve cover replacement for these engines with an updated PCV system?

 

They have the correct valve cover for whatever year LS engine you have.

 

I have a Gen III engine. I need a valve cover from a gen IV engine because they have an updated PCV baffle system. I have been told that Gen IV engines have multiple part numbers for their driver side valve covers, which probably means multiple designs. I'm looking to replace the stock valve cover on the '04 5.3 I have with an updated part from a newer, Gen IV engine. Since there are multiple part numbers available for Gen IV engines, I'm curious if one of those designs works best with retrofitted onto a Gen III.

Has anyone replaced their valve cover with the updated design?

 

Yes.

Yes. The one from Dorman. It's for your motor, and is widely available; rockauto for example. Just go look it up for a 04 Av. Oh wait... how would I know that they have one for that application? And that it solves the problem? Hmmmmm…….

 

Go on Dorman's site and see what they have.

 

LS3 and LS7 valve covers are compatible with Gen III's. The baffling changed in the Gen 4 valve covers due to the offset rocker arms.

 

As I mentioned in the other thread, I just did a quick search on CorvetteForum and found a set of LS7 covers for $100. The guy will prolly go $75 shipped or so. I’ve bought 2 sets from guys over there. Those Vette guys put like no miles on their stuff and the parts are always super clean.

 

Not sure, but here may be a valve cover part number variation due to the PCV connection port type. When recently replacing the PCV dirty tube on my Gen IV 5.3L, the dealership showed and brought to the counter 2 different PCV tubes as being available. One was an all plastic typical quick-connect fitting, and the other was simple slip on rubber tube ended. This tells me there may be 2 different tube connection port types. Sure, probably easy to interchange or use them in place of each other, but still, his concern of there being multiple part numbers is likely somewhat correctly founded.

 

Thanks Formula. What I'm really looking for is specific info as to which types of new covers work, how many different types there are and what their part numbers are.

There is much speculation on the Dorman part as to whether it actually has the updated baffles or not. Some that have ordered it say yes, some say no. There seem to be multiple generations of these.

 

I finally was able to find this info in case it may be helpful:





This is GM's third attempt to mitigate the oil consumption issues plaguing LS1 engines and 1999-2013 LS engine trucks. For some reason the engine eats oil through the PCV setup and people who run catch cans catch a significant amount of oil. For millions of engines that don't it pools up in the intake. I was surprised when I pulled the intake manifold on my truck to see oil weeping out of the intake runner outlets.

New GM valve cover. Includes new gasket and grommets. Part number 12570427 for 2009-prior LS engines which has the hose connector barb for the PCV tubing. 12642655 is for 2010-2013 LS engines which uses a push on fitting connector.