Yup, howdy , looking for suggestions to improve mpgs on 04 6.6 durimax gmc 3/4hd. Just drove down from FBKS to SF,cal, did about 17mpg for the total 70-80mph, small enclosed trailer with H.D.and tools.I know keepin my foot out of it helps alot. I am totaly stock w 55k ,lly 5speed allison.
run synthetic fluids all around, open exhaust and air intake....every truck is different so mpg increases vary....are you sure your trans is not a five speed auto?
yup,5 not 4 Yup,is 5 speed not 4. Are you using a tuner? I have syn in the cases , but not in the engine or 5speed , yet. Was one of my next moves. Do you use any additives ? cetene boost,besides injector cleaners, how frequent? Fuel was not good in Ak for a wile, has gotten better. Canada has the best diesel , but expensive. Thanks for your time.
Yup, 5speed not 4 Yup, is 5speed not 4. I have synthetic in evrywhere but the engine and trans,yet , is one of my next moves. I found syns great stuff for cold climate. What about additives, cetene boosts and injecter cleaners, frequency?
Welcome! Syn in the motor and trans will help. The motor will smooth out a bit and is good for about .5 mpg (sometimes more, sometimes less). We use Amsoil here in the shop and in our personal vehicles. Additives. Well, in my Dodges, I am in the habit of running Amsoil Diesel Concentrate (ADF) every tank. Pretty reasonably priced per bottle when you use a bottle to about 3 tanks on the Dmax (small tanks!). As for your trans, one thing you can do for better mileage on the highway is a 6 speed conversion. Suncoast offers it, pretty reasonable considering it converts your 5 speed into the new 6 speed. Basically gives you an extra overdrive gear, which cruising should be good for about a 10% increase in mileage, and gets you a performance VB to boot! Tuner, well, I like Diablosport for its power to cost ratio. Very affordable. If you are a demanding type that wants some serious power, PPE is the only way to go. Middle ground would be the Edge Juice with Attitde. Good power, adjustable on the fly, and includes gauges. All 3 will check and clear trouble codes. Hope this helps!
dont have much or good expierence with tuners so far, i pull heavy loads daily...fuel additives are a dime a dozen..lucas is good and almost everywhere and howes makes good stuff as well. i have not used AMSOIL but about ready to give it a try from DIESEL NUT...just used the red line diesel cataylst and smothed out the idle very nice but milage was the same...i have also used CONKLIN about the same as RED LINE, so far LUCAS and HOWES MEANER KLEANER have been the best....well hell the big trucks use it all the time over the road and it works for me....
alaskadave update Yup, waiting for my posi-locker rear end to get put in before I play with the tuner. Opened up stock air box to let in more cool air and add even better airfilter that fits retro stock air box, and oem air filters will still work, but there are better aftermarket filters made to breath and filter better than oem and are cheap compared to a full blown changed air in system. Hypetech is a basic tuner that lets me control everything I need to control, and leaves me room to get new gadgets such as gages and egt digitalized. 4 speed with overdrive makes 5 speed, firm up shift points and spin both back tires, in Ak in 4x most the time, winter is long there. Want to know for sure am spinning 3 of the four tires, can't do much for the front wheel limited slip. Allison possi is 1500.$ installed.And bolted down a 100 gal transfer tank in the bed. :stir:
update on alaska dave Yup, am in Phoenix, my tuner clicked up to stage one has bumped me up to 22mpg hympgs. And can feel the few new ponies . kept the rev limits the same , for 85mph tires, and am enjoying the run. AM looking at purchasing a new toy hauler to pull back to Ak this spring. and there are lots of things to look at before I bust a move. Am thinking of staying with bumperhitch style, thou the 5th wheel floor plans and roadworthyness are looking good too. RV show here in Phoenix , I like go look.:stir:
