Attention: TDR Forum Junkies At 22K miles, I decided to make the switch to synthetic motor oil. I reset the overhead MPG meter and was amazed to see the number dancing between 19 and 20, even over 21 for a while, on a 100% freeway drive, unladen. Surely an anomaly! Well, into the second full tank, the overhead has settled to about 17 mpg in my usual mix of local freeway/stop and go city driving. This is a full 1. 5 MPG, approaching 2. 0 MPG improvement! 15. 3 MPG seems to be the most common mixed driving MPG calculation I have achieved in the past, with up to 17. 5 on long-distance freeway cruises. I validated the overhead within . 3 mpg of actual on the first tank's hand calculation, a variance that is consistent with the past.
I was one of the complainers two years ago. As my 2004. 5 CTD 600 was one of the first 100 produced, it took a while to hear that most owners were disappointed with fuel economy. I had the reflash done at the dealer - worth perhaps . 5 MPG, argueably. Everyone said "wait till you get some miles on her. " That was worth a couple of tengths, maybe, at 22k. However, I would be stretching to say the truck got 1 MPG better than the day I drove it home until just before the oil change.
Previously I ran Chevron Delvac. The new oil is Valvoline Premium Blue Extreme 5W-40, combined with a Fleetguard Stratapore filter. I chose this synthetic for the Cummins endorsement and off the shelf availability over Amsoil, Royal Purple and other fine products. BTW, for this or other lubricants, check with local petroleum distributors before buying at Walmart, Autozone or other consumer outlets. Most distributors will sell over the counter retail to little guys. PBE was just over $80 for a case of four one-gallon containers at Canyon State Oil in Las Vegas. The same quantity from Autozone would have been about $150 in quart containers.
I was only looking forward to reduced change intervals and longevity benefits, but now I am stoked about the MPG too! It's looking like an honest ten percent improvement. I wonder what will happen when I go synthetic in the transmission, transfer case and differentials?
I was one of the complainers two years ago. As my 2004. 5 CTD 600 was one of the first 100 produced, it took a while to hear that most owners were disappointed with fuel economy. I had the reflash done at the dealer - worth perhaps . 5 MPG, argueably. Everyone said "wait till you get some miles on her. " That was worth a couple of tengths, maybe, at 22k. However, I would be stretching to say the truck got 1 MPG better than the day I drove it home until just before the oil change.
Previously I ran Chevron Delvac. The new oil is Valvoline Premium Blue Extreme 5W-40, combined with a Fleetguard Stratapore filter. I chose this synthetic for the Cummins endorsement and off the shelf availability over Amsoil, Royal Purple and other fine products. BTW, for this or other lubricants, check with local petroleum distributors before buying at Walmart, Autozone or other consumer outlets. Most distributors will sell over the counter retail to little guys. PBE was just over $80 for a case of four one-gallon containers at Canyon State Oil in Las Vegas. The same quantity from Autozone would have been about $150 in quart containers.
I was only looking forward to reduced change intervals and longevity benefits, but now I am stoked about the MPG too! It's looking like an honest ten percent improvement. I wonder what will happen when I go synthetic in the transmission, transfer case and differentials?
