Well here you go... 27.2 MPG and 106 Mile trip from home to McCall, ID then back home the into Riggins, ID and then back home. All up and down hills. But I finally caught up to ISX's 27 MPG... :woot:Sorry for the blurry pic but I turn off my camera flash to get the photos without the flash blocking out the screens.

How long were you coasting to do that?

Cruise set at 55 MPH all day long except for other speed zones for city speed limits in McCall and Riggins is 25 MPH. Here is my route of travel. http://goo.gl/maps/7U93D Now there is a few extra miles added because of forgetting stuff in McCall and having to turn back around and go back for one last part I was looking for. I wish I could it day in and day out but like tomorrow I'm hitching up the BigTex 70TV and heading for Ontario for some stuff from Home Depot that total for the tank will be trashed.

:thud:Nice!I always cruise at 55, but I doubt I will see those numbers.

All kidding aside that is an accomplishment. I am proud of you.

Well back to normal dayz again. :rolleyes:Hitched up the BigTex 70TV and hauled to Ontario, OR for shopping and tried all my tricks to improve the MPG towing but its kind of hard with a 5 foot tall tailgate that is screened but its still a good wind drag. I managed 17.5 MPG round trip to Ontario, OR and back home again. I even stopped and scaled on the way home...Truck Front Axle ............ 4,080 pounds (Normal Curb 4,440)Truck Rear Axle ............. 3,340 pounds (Normal Curb 2,860)Trailer Axles .................. 2,040 Pounds (Dry Weight 1,800)Gross Weight ................. 9,460 Pounds

ok, so... what did you change/adjust/manipulate to get that 27 mpg? Why the sudden jump

Not using 5th gear up hills any longer. Using 4th gear 1:1 direct drive (2,100 RPM). So like my entire trip to McCall is mostly uphill I see roughly 150*F EGT drop in 4th compared to 5th so the MPG's are higher as well. So if the EGT's are down you know your burning less fuel. Even up hill I'm average at 550-600*F compared 700-800*F in 5th.That and the fact IAT was close to actual fooled temp at 135*F for the day. (Fooled temp is 143*F) Boost remained below 5 PSI till I hit the 7% grade of course it rose too but not much above 10-12 PSI.Nothing else changed. As for the trailer with the large tailgate I did find the optimal 20-25 MPG range too is right at 40-45 MPH now the wind drag is reduced enough to gain the MPG's. My RV is about the same I can start touch high teens at 40-45 MPH.

And here you told me 30 was impossible and here you have a truck 1500lbs more than mine, several inches taller getting 27...... Are you a believer yet BTW, what were all the vitals reading on this run?

And here you told me 30 was impossible and here you have a truck 1500lbs more than mine, several inches taller getting 27...... Are you a believer yet BTW, what were all the vitals reading on this run?

Vitals I can give... Cargo and Passengers: 2 on board (350#), groceries (80#), 3/4 Tank of fuel High Temp Outside: 105*F Speed: 55 MPH or lower speed limits never exceeded 55 MPH. IAT: Forced to 143*F checked actual a few times and it varied from 132-138*F. Coolant Temp: 193-195*F Boost: 1.5 to 3 PSI on the flats and tried not to climb much above 10 PSI while climbing grades. EGT's: (450-500*F down) (550-600*F up) on average max'ed out at 750-800*F climbing 7% grade at 35-40 MPH (not count slowing down for corners acceleration.) Tire Pressures: Front Axle: 58 PSI - Rear Axle: 37 PSI Fuel was treated for 128:1 ratio 2 cycle oil. Air Conditioning was on and used. Elevation: McCall, ID 5,100 feet approx. Home: 2,800 Feet measured. Riggins, ID 1,800 feet approx. Going up I used 4th Gear all the way from home to McCall, ID then at select times that I could I would use 5th gear on the way down. Same with the Trip to Riggins, ID I used 5th gear selectively and return home I used 4th solely climbing back home. Last two days I've been dragging around the trailer and got 17.5 MPG yesterday with 200# (GCW 9,460#) of construction supplies and today got 16.8 MPG dragging the trailer with my ATV (~900#) in the back of the trailer. Still using my same tricks.

Well then my trucks a piece of crap. I got 26.8 BTW haha. WITHOUT the damn A/C, so I'm not sure how you did it with it. And mine was 55mph rolling hills perfectly straight back and forth 40 miles at a time (to work then back). Plus you have 4wd etc. Actually was this with the camper shell? I mean really this makes mine look like crap lol. Makes me happy though cause it means I have lots of room to improve. But just years ago you were topping out at like 20, so what all have you figured out exactly?Thing is, I get the same mileage be it 100 or 0F. I have got the same 26.8 at 55 in both scenarios (actually tested both temps).

Riiiiight... I have ALOT of room to improve then! 10mpg towing my 5th TH and recently 12-13mpg. I was getting 16-18mpg. Dunno what happened.

Well then my trucks a piece of crap. I got 26.8 BTW haha. WITHOUT the damn A/C, so I'm not sure how you did it with it. And mine was 55mph rolling hills perfectly straight back and forth 40 miles at a time (to work then back). Plus you have 4wd etc. Actually was this with the camper shell? I mean really this makes mine look like crap lol. Makes me happy though cause it means I have lots of room to improve. But just years ago you were topping out at like 20, so what all have you figured out exactly? Thing is, I get the same mileage be it 100 or 0F. I have got the same 26.8 at 55 in both scenarios (actually tested both temps).

Remember this is only a day trip 106 miles one time hitter. It was day after day tank total out and pump fill type. I'm hoping to do it again the same type of trip and hit those kind of numbers again. If can then I consider it real but if its just a single high spot hitter well... The RV275 injectors from CajFlynn were OK but the pop pressure and nozzles wasn't correct nor a clean spray. The +50HP injectors are much cleaner spray pattern. Then after my last big haul 430 miles to Heyburn Park with the RV the truck has changed in performance. I think there might of been carbon build up or something? (Can't explain it) Ever since then the MPG's have been slightly strong across the board. Canopy/Topper was on. I've got little to no reason to pull it off now being I've got the BigTex 70TV I can hitch up to haul big stuff now. Winter is coming we'll see what happens with these new +50 Injectors through the winter now. You got to remember when I got the +50HP injectors they where flow matched and pop tested to match as well across all 6 injectors. Not just 6 injectors pull off the shelf and tossed in a box and shipped. Even worse to expect good anything from 400k mile RV275 injectors not even the right pop pressure at the end 260 bar?! When it should be 310 bar. They were fun but now seeing the difference between OK and done right is way different even in power.

That is some great fuel mileage, I'd like to get that everyday!!!

That is some great fuel mileage, I'd like to get that everyday!!!

Well even the last 3 days have been 16-17 MPG because of trailer hauling. Even today with doing service work to the truck and quick blast up the highway and back (2 miles) its barely 15 MPG. But tomorrow I'll most likely be heading to Grangeville, ID for sprinkler parts. Nice long haul up 7% grade for 7 miles.

Well here you go... 27.2 MPG and 106 Mile trip from home to McCall, ID then back home the into Riggins, ID and then back home. All up and down hills. But I finally caught up to ISX's 27 MPG...

Very nice!

Your SGII must work different than mine, my CMG resets every time I shut the motor off.

So if the EGT's are down you know your burning less fuel.

Not always true, it can be cooler from higher airflow and not less fuel. Generally speaking that's true, but not always.

Well back to normal dayz again.

Hitched up the BigTex 70TV and hauled to Ontario, OR for shopping and tried all my tricks to improve the MPG towing but its kind of hard with a 5 foot tall tailgate that is screened but its still a good wind drag. I managed 17.5 MPG round trip to Ontario, OR and back home again.

I even stopped and scaled on the way home...

Truck Front Axle ............ 4,080 pounds (Normal Curb 4,440)

Truck Rear Axle ............. 3,340 pounds (Normal Curb 2,860)

Trailer Axles .................. 2,040 Pounds (Dry Weight 1,800)

Gross Weight ................. 9,460 Pounds

Your truck is light!

Why are 2nd gen's so much lighter than 3rd gen's? I know they are, but that's a big difference.

Even at my lightest (still have normal gear in the tool box) I am still 1K heavier up front.

Front ..... 5020

Rear ...... 3360

GVW ...... 8380

How did you drop almost 400 lbs from normal curb, it doesn't seem like you have enough RAW or tongue weight for that big of a drop? Even with 1250lbs of tongue weight on a 18" hitch and no W/D I drop 700 lbs, and you don't have anywhere near that tongue weight.

Just scaled again at Primeland in Grangeville, ID with 2 passengers, 1 dog, half tank of fuel no cargo other than typical tools. Front Axle ------- 4,400# Rear Axle ------- 3,080# Gross Weight --- 7,480# Trip to Grangeville, ID and back to home. Vitals I can give... Map of travel http://goo.gl/maps/ODZLN High Temp Outside: 85*F Speed: 55 MPH or lower speed limits never exceeded 55 MPH. IAT: Forced to 143*F checked actual a few times and it varied from 120-125*F. Coolant Temp: 193-195*F Boost: 1.5 to 3 PSI on the flats and tried not to climb much above 14 PSI while climbing grades. EGT's: (400-500*F down) (550-625*F up) on average max'ed out at 800-850*F climbing 7% grade at 55 MPH for 7 miles. Tire Pressures: Front Axle: 58 PSI - Rear Axle: 37 PSI Fuel was treated for 128:1 ratio 2 cycle oil. Air Conditioning was on and used. Total MPG --------- 23.5 MPG Total Distance ----- 121 Miles Maintenance done before trip: Fuel filter, Transfer case fluid changed, Power Steer fluid flushed, and other fluids where checked. Day isn't over yet I still got to haul back to Riggins, ID to install oxygen sensors in a Toyota truck and then head to fire meeting. So I'll post the final for the day later this evening.

Looks like a nice day for a drive. I could have swore there was quite a bit of 60mph speed limit on that route??? I don't drive it nearly as much as I used to, but I know some of it is 60. Why only 37 psi in the rear tires? Isn't that just enough air for a RAW of 2800 lbs?

All 65 MPH from Riggins to Grangeville but very little traffic so I set the cruise and relaxed.As for tire pressure I need to tweak them a bit. Front: 4400 / 2 = 2200 / 3042 = 0.72 x 80 = 57.8 PSIRear: 3080 / 2 = 1540 / 3042 = 0.50 x 80 = 40.4 PSI (so I'm 3 PSI off...)

All 65 MPH from Riggins to Grangeville but very little traffic so I set the cruise and relaxed. As for tire pressure I need to tweak them a bit. Front: 4400 / 2 = 2200 / 3042 = 0.72 x 80 = 57.8 PSI Rear: 3080 / 2 = 1540 / 3042 = 0.50 x 80 = 40.4 PSI (so I'm 3 PSI off...)

Okay good, I am not going crazy :-) I'm a big fan of tire pressure, I think you get better mileage with higher pressure. I like to run as much pressure as possible without effecting the contact patch of the tire. I recall reading a article by Cummins where under-inflated tires really decrease mileage, but overinflated helped increase mileage. It's two fold, rolling resistance and change in tire shape over uneven surfaces taking additional power. One of the reasons switching to 19.5" wheels/tires show an increase in mileage is the harder rubber rolls easier, even thou they are heavier.

Might work good for highway usage but I also got to figure in dirt road operation too. Slightly softer pressure tend to keeping the tires locked down better on gravel roads. Yes. I will admit I like the slightly high pressure on the highway but I bounce between dirt and pavement so often I got to split the difference.