Hey Fellas I have a very high mileage 99 GMC (150,000) and wanted to know if I could put a 6.0 in there and have to PCM tuned to The 6.0 and still pass smog in California? Also what do the 6.0 motors run in price?? Thanks for any help.

 

I had no problems passing with shorty headers and high flow cats.
I had a way bad tune at the time running way lean.
Low mileage 2002-2005 6.0 $1800-3000 complete from a wrecking yard.
Early 6.0 had cast iron heads late 6.0 have aluminum.
6.0's eat a lot of gas

Good luck.Hope this helps you out.

 

As long as the engine is the same year or newer and you retain all emissions equipment you should have no problems.

You know though many smog places do not even check for that kind of stuff... They look for the obvious mods, SES lights, and then do a sniffer test. Done.

 

Yep, the motors are identical from the outside. Only the block stampings or head #'s give away the 6.0L from the others. Proper tune and the original smog items will pass no problem.

 

Cool thats what I was thought but was not sure. It will have all the smog equipment with smog legal headers. Does anyone know what are the casting number for a 6.0 I know that the 4.8 and 5.3 are stamped on the block but are the 6.0 motors stamped also? What is the difference between a LQ4 and a LQ9 is it just compression and cam??? Thanks for the help..

 

Are the intakes interchangeable?