Filled her up again at same station. Topped it off with 18.0 g. after 377 miles. That is 20.9 mpg, computer said 18.5mpg. Total mileage on my 2003 CTD is now 3795. Previous fill mileage was 19.2mpg. Same type of driving, no towing, up and down these Sierra Mountains.

 

Hey, that's good. I guess I better keep a log. I sort of lost track when I put in the extra tank. Put some ??? fuel in to test the installation and connections and can't remember how much. Just having too much fun driving it to worry about the mileage. 8)<br><br>Bob

 

;D Sweet! ;D<br><br>I've plateaued at 19.0 (actually it's 19.075, but I'm not compulsive - no, not me!). I think with the cold weather and winter fuel, I may not see 20 'till Spring. <br><br>Could be worse, I guess. ;D<br><br>Best to y'all<br>Bill

 

Still only about 16ish here. Gets worse on the highway (per computer)...knew I shoulda got the 6.0 : ???

 

Paddzz<br><br>Your only problem is the 4.10<br><br>Hunter

 

I am getting mid 18s and that is in cold weather and with a 4.10 axle. The computer actually measures fuel flow into the engine and miles traveled. The pump and paper method is very dependent on how you fill up each time but should be accurate over several tankfuls. I have found that my paper calculations are very close to the computer if I am consistent in how I fill the tank each time. FWIW.<br><br>Happy Holidays,<br>Casey

 

Yeah - The accuracy of the 'puter readout on these trucks has been a topic of discussion a few times. Some report their MPG readouts are right on, others do not. Guess it depends on the truck, the consistency of the fill-up, yada yada.<br><br>Mine's doing pretty good on this truck. So far, it's been accurate to within about 1/10 MPG. My readout says 17.6 MPG. Corrected (x 1.09* to compensate for my tires) it's 19.184 MPG. By paper and pencil I get 19.075 MPG. Darn close, if you ask me.<br><br>* verified by GPS and certified by radar<br><br>Best to y'all<br>Bill

 

Talking about fill up.<br>I like to fillup all the way to the top so as I can see it.<br>Problem is after the first 22 -24 gallons the foam is so bad that it takes another 5-10 minutes to get that last 2 gallons in.<br>Does anyone have a trick to eliminate the diesel from foaming. I did notice that when I put the Marvel oil in first it seems to help , but not much.<br><br>As to mileage, I just started to go over 20mpg on the highway at 4400 miles. On paper and computer. First 3,000 was 15 to 18 mpg.

 

2100 miles, computer says 17.8, about 1/2 city 1/2 highway. Towed nothing but my fat but yet.<br><br>Perhaps Sierra is doing better because the Cummins LIKES to climb ;D and flat old Ohio just ain't no fun for her?<br><br>

 

UTAH,
my cputer was 2/10ths mpg low until the weather turned cold then suddenly it was 2 mpg low. It could be that cputer doesn't understand the coefficient of expansion and how temp effects volume, low temp, less volume. Since I fill a the same station and usually about the same time of day their volumes should be consistant. However, recalling my days in the 50s pumping gas to meet college expenses, we always had a couple of pumps that went waaco a couple of times each month and over pumped.

I'll keep filling at this station because they are a high volume station with low price. If mileage is consistant then it is more likely to be correct. PADZZ, note that I have the 4.10 axle, with 5 spd and the infamous SO Calif version. Another thought, this is the first tank after getting the new bearings in rear axle, less friction in the drive train.

 

Mine is running very close to the computor (17.5 to the US) Gal.) some city but mostly hiway driving on winter fuel. We haven't had any cold weather yet in the Edmonton area. Like Sierra Phill, I am also inclined to try and fuel at the same station and same pump if possible and I made a Exel spread sheet with the help of my daughter ( I am computor stupid) and I like to keep a eye on the fuel consumption. So far I have not towed my fifth wheel trailer but our roads are clear and dry and if it does not snow tonight I will hook it up and take it for a test drive tomorrow.

 

We are trying to prepare for our next trip with 5er. About Jan 6th we will join the Snowbirds for a couple of months. <br><br>This weekend is somewhat of a bust. El Nino hit with a fury and we are having heavy rain with periods power outages. At the summit of the Sierra in our county today they clocked 130 mph wind gusts, not too unusual for our winter storms. We had some 60 mph gusts at our place. Several Ponderosa Pines have snapped of in this area.<br><br>Jim O, Hope you are able to tow tomorrow. If old man winter holds off in your area give us a report.

 

My mileage is only staying around 15.7-16.0 on the puker. Is that real bad? :

 

Fire<br><br>How many miles you got on her? Should be a little better maybe, have you read the part about break-in? And DC telling you if you don't load her down within the first 6,000 miles the final fit and finish of the engine will take much longer to achieve and will not run correctly nor get the correct fuel mileage?<br><br>I started at 17, up to 20.4 the best now with 4,000 miles<br><br>Fuel mileage is in the hands of the pumper and the penciller in the event you didn't know. You will hear all kinds of figures, but, many don't fill the same and fill to the top to get exacting figures.<br><br>In other words, some of the figures will be blowing smoke like a 1st Gen! <br><br>Hunter

 

When you say &quot;load her down&quot; Do you mean like towing or what? Kinda confused on that one. thanks