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locomotive breath · 02-15-2012, 12:37 AM

Here is my contribution to this thread. I picked this up last week about 30 miles from home. It is a 71' GMC 6500 with a really good running 427, 5 speed, 2 speed rear, and air brakes. The previous owner passed away a few years ago and it looks like he took pretty good care of it. I plan on using it to pull my 32' GN trailer.

I still have to get the title transferred, change all the fluids, and clean it up good. I am curious as to what kinda mileage I can expect though. It has 6.50 gears on the high side and 42" tall 10.00-20s which should work out to 3400 rpm at 65 mph. I'm hoping to average 7 mpg towing approximately 16,000 lbs. Anyone think that kinda mileage is possible on long trips if driven right?

02-15-2012, 12:37 AM	#245
locomotive breath Registered User Join Date: Apr 2008 Location: Royse City TX Posts: 43	Re: 67-72 C/K/T-40's-90's! Here is my contribution to this thread. I picked this up last week about 30 miles from home. It is a 71' GMC 6500 with a really good running 427, 5 speed, 2 speed rear, and air brakes. The previous owner passed away a few years ago and it looks like he took pretty good care of it. I plan on using it to pull my 32' GN trailer. I still have to get the title transferred, change all the fluids, and clean it up good. I am curious as to what kinda mileage I can expect though. It has 6.50 gears on the high side and 42" tall 10.00-20s which should work out to 3400 rpm at 65 mph. I'm hoping to average 7 mpg towing approximately 16,000 lbs. Anyone think that kinda mileage is possible on long trips if driven right? Attached Images __________________ '50 GMC 350 COE, 702 V-12 / 4L80E powered '71 GMC 6500, 427, 5 spd Last edited by locomotive breath; 02-15-2012 at 12:46 AM.