Looking for any information regarding 3/4 ton 4x4 suburbans with the Vortec 7.4. Are these engines reliable? Any specific problems? Do they react well to mod's? Where is a good place to buy upgrades? Doesn't seem to be alot of info out there about these engines.

Thanks-

 

YES THEY ARE VERY GOOD ENGINE, THEIR THE VORTEC FAMILY. WE MOSTLY HAVE THE LS1 BASED HERE. i HAD THE 350 VORTEC AND IT WAS A GOOD ENGINE. fROM WHAT i DID i SAW GOOD INCREASE. i WOULD START BY EXHASUT, HEADERS, INTAKE AND CHIP. IF YOU HAVE ALOT OF MONEY GET A SUPERCHARGER YUOU WILL BE VERY HAPPY WITH IT. i WOULD MAYBE CHECK SCOGGIN AND DICKEY PERFORMANCE PARTS OR SOMETHING LIKE THAT.

 

Reliable? Yes, I would say so.

Specific problems? Some sip oil, some chug it. Some run hotter than others. They all guzzle fuel and it seems most fuel pumps only last ~75K miles. Also, you'll probably have to replace the intake manifold gasket at one time or another.

Here's a link to give you some info:
http://aplsweb.com/Topics/Engines.htm
http://aplsweb.com/Topics/Topics.htm

 

I had one they are very reliable but get horrible gas milage and aren't as fast as a 6.0.I had one for 5 years and thought it was great until I bought my Tahoe.

 

yea watch out for the back intake manifold, its not cheap to ahve someone fix it, my z71 with superswampers and 4 inch lift best got 12mpg. on the highway. they do suck down alot of gas but they are very powerful engines.

 

Good info!!!!!!

Thanks.