billbro

Nope- both are fully assembled, but still no info other than that. I believe Doug Scott is probably correct, that they are CNG heads

that's my problem- doug scott wrote: "they appear to be the same" Duelin wrote:#12562317=$197.77 , #12562319=$384.80 -because if they are the same I would like to get the ones that are 1/2 price!! I've sent an email to gmpartsdirect.com asking for more info so hopefully they can explain it thanks for the help, bill

hello all- looking to get rebuilt heads (317 casting) for my 6.0l and came across a pair of NEW heads for the same price. All the GM parts websites say I need part #12562319 heads (317 casting), the new ones I found are GM part #12562317 heads (also 317 casting). Does anyone know the difference (if any) between these two heads? Everybody seem to say "all 317 casting heads are the same", true? Then why the different part #? The price difference between the two part # is almost double, and for the life of me I can't find out what the actual difference is. I would like to get the less expensive heads, but only if they are correct. Any and all help is appreciated, thanks.

Had it happen to my 2004 GMC 2500HD 4wd @ about 75k - no oil pressure at start up one day. Turned out to be the pressure relief valve (which is built in to the pump) had a piece of crap in it and wouldn't allow it to close, so no pressure. Changed the pump out and so far so good @ 128k.