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Big Port Jimmy 6 · 02-25-2010, 10:02 PM

With an over drive the 3:42 gears are actually 2.39 in over drive the 308s are 2.15. The 342 will also help you come off the light a little easier. I usually like a 3:73 (2.61) with the overdrives, but with the torque of the big block you will be ok a little taller gear. Jay

02-25-2010, 10:02 PM	#9
Big Port Jimmy 6 Addicted to Rust Join Date: Dec 2009 Location: Abbeville SC Posts: 1,030	Re: gas mileage With an over drive the 3:42 gears are actually 2.39 in over drive the 308s are 2.15. The 342 will also help you come off the light a little easier. I usually like a 3:73 (2.61) with the overdrives, but with the torque of the big block you will be ok a little taller gear. Jay __________________ Current trucks: (48 GMC100 320 inliner) Gone (48 Suburban in pieces) Sold 87 GMC CCSB 5.3 4l60E Daily Driver ECTA National record holder XO/PP We never really grow up, we just learn how to act in public.