454 mileage?

jet mech · January 21, 2002

Hi all,

On the prowl for a new tow vehicle. Need to upgrade from my K1500 to a C2500 to tow our 7000lbs(gvw) 25ft Alpenlite 5er(980 pin wt.-150lb Reese slide hitch) Can't seem to fit a new Duramax or 8.1 into our current or future budget so I thought that possibly a '98-'00 3/4 ton extracab with the Vortech 454 would work for us. Questions: do you guys think that a truck like this would have enough pull to move my rig in the Western or Eastern mountains using the 3.73 rear gears(for a bit better milage solo). What could a truck like this be expected to give MPG wise with this type of weight and that gear ratio? How much would power and MPG be affected using the 4.10 gears? Will the 4L80 tranny hold up to this kind of RVing?

Thanks for the help.

NeXuS1 · January 21, 2002

my dad's 97 K2500 with 454 and 3.73s gets around 10 mpg towing his 5th wheel. my 95 K2500 with 454 and 4.10s gets about 8-9ish. hes running around 11-12 mpg in town, while i get about 10mpg in town.

the towing numbers are not all that great since only ones i can remember are from out trip the oregon coast. coming from Nv we hit just about every mountain in the way. and thats a lot of up hill climbing, which kills the milage. anyways. a C2500 should get little better milage. if you drive like a normal person you shouldnt be too unhappy with the milage.

as for towing. its great, just make sure its an 8 lug 2500 to get the better brakes, and stuff. the 6 lugs are exactly the same as my olf half ton.

hopefully it was a little helpful for you.

btw he has a 25' nomad, somewhere around 6700lbs. and i have a 21' sport hauler when fully loaded (like it was on the trip to oregon) is about 7000+

bluenote · February 1, 2002

I inherited a 99 GMC 2500 with the 454 and 3.73 rear end. It had the 8 lug wheels/load range E tires/trailering package, etc.... This truck pulled a 10,000 pound 5er round trip from Michigan to Florida, several trips around Michigan, and round trip from Michigan to New York, including the Catskills. Towing mileage ranged from a low of 6 mpg in the Catskills to a high of 9 mpg within the state. Unloaded, I could get about 11-12 mpg around town, 13-15 mpg on the highway, and once even hit 16 mpg on the expressway. Although this truck was technically a little underpowered for the RV it pulled, we could walk right down the road with it, no problems. You should find the truck to be more than adequate for the set up you're looking at. Have fun camping!!