I have always got 200 miles from full to the red zone on my gas gage till now. Now I get 230 and over and that translates to 18 MPG and up with city driving. The only things that are different that I can think of are that I changed my CPS in January and switched over to synthetic rotella in December. Back in late February I goofed and left the plug out of my HPOP and lost all of my oil and the only place open was a Mobile gas station and they had Mobile 5w40 synthetic so I had to use that. It was after the switch to the mobile when I started to notice the difference in mileage. Can the synthetic make that much of a change in mileage? Or is it something else that I am missing?
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Probably leaving the plug out of the HPOP, this way it has fresh oil

 

weather has warmed up, fuel is bleded accordingly and you will get better milage all depending where you live as well. I notice my truck runs better with synthetic oil soo....

If your pulling off 18mpg in the city, your walking all over my 15 city/highway.

 

This winter I've been getting about 15mpg mixed driving.

Summer I usually get about 18mpg mixed, 22 highway if I'm nice to it.

Could just be some bad fuel...

 

I did have to switch over to a mobli oil when i left the plug out. I thought I damaged my motor because I am using so much more oil after the plug thing but now I am thinking it is true that synthetic will leak a lot more then standard oil.


Try using Mobil synthetic!!


Thought about the fule thing but I never did see a change in milage between summer and winter. Might have something to do with the fact that I have been using the stuff at the pumps latley but cant be that much of a diff.

 

I'm goin outside and takin my hpop plug out for that kinda mileage. HA!

 

Have fun cleaning up the mess!

 

Winter diesel additive = poor economy. The additive is added as it's being loaded into the tanker truck prior to the gas station.

 

I think it's just the summer fuel coming back in too. I went about 250 miles on my front tank the other day. Also my new tractor, well 2 years old, runs like a scalded dog now, Untill I brought home 250 gallons of fresh summer grade fuel last week it was running like a 3 legged dog that lost a fight. I was able to pull my plow in 4th gear yesterday, throttled down to about 1400 rpm. That never happened with winter fuel.

 

Mobile is not a True Synthetic, it is a Synthetic blend.

Synthetic oils can make a load of difference if your motor is suffering from poor performance from DINO oils.
Lots will say that the additive packages are the same, so just use the cheap stuff. I am pretty sure that is not the case though.
Cheaper oils are made from poor'er quality stock than a good synthetic. Mobile uses a decent stock oil to make theirs, even though it's a blended oil.
The better stock gives you better lubrication.

Now here is where people argue, IMO.

A better oil will allow the engine to perform better. Synthetics are designed to do these things better than Dino oil is. With the high tolerances in our trucks, the better the oil you use, the better performance you will get. If you have a High OCI rating like 3k miles, instead of 5k miles, then using 25dollar a gallon oil might not be right for you and you should stick to something like rotella full synthetic. Break down of the oil is important, and I believe personally that synthetic doesn't' break down as fast as a DINO oil, no matter what the additives are.

I'm kinda getting to into this.

Basically, a synthetic will allow the engine to work just as hard with less wasted effort.
Friction causes loss of power basically, so the better you lubricate your motor, the more efficient it is.

Now yes, the summer fuels give you better mileage generally, but if you noticed he said he always got 200 miles to a tank.

And for the other person here who was talking about the HPOP drain, its not a closed system, its fed from the LPOP and the oil goes back into the system after its ejected from the injector. I think they said it takes around 30 seconds for the oil to cycle? I forgot what TJ said it was.

 

Sheesh! just joking. Do you seriously think I would leave my oil plug out on purpose? Happy Easter Guys.

 

Thats funny stuff right there jack.

 

So I was reading the owners manual on my truck and is says that you need an oil that is API certified to at least CD. I run Mobil clean 5000, which is API certified CF, so it surpasses the cleaning and chemical neutralization characteristics that are required for this motor right? The clean 5000 is a conventional oil with 16% extra cleaning agents in it to keep your oiling system from building up sludge and other poop.

I have always run synthetic in my pre-runner, and always run Mobil products. Aside from running a full race-grade oil, Mobil is suppose to be the best readily available oil on the market. You guys can have your brand loyalties, but that's where mine have always been, and it's never let me down. I beat my prerunner for 5k per oil change, and it spins like a top with 170k on the motor. However, Mobil synthetic isn't API certified for use in diesel engines. I have never seen that Mobil 1 diesel synthetic at any parts places around these parts, or else I would run that. I also run the Mobil fleet oil filter on my PSD, seems to work well.

So I guess the questions that I have are:

1. What oil do you guys normally run?
2. What is your oil change interval?
3. What filter do you run? (non-bypass)

I have heard alot of guys run rotella, or delo, but I've stayed away from them because they've always seemed like a cheap fleet oil option where I could run something better. I've also heard guys running oil change intervals as high as 15k. I know some of you are going to poop yourselves when you see that 15k, but alot of people I know run 10k oil changes (like myself) and have high mileage motors that run great. I am thinking about running a test on my oil for the next two oil changes, taking samples every 1000 miles and sending the whole thing off as a package at 10k to have them all tested. Most of all, I'm wondering about the three q's above because I want longevity.

oh and BTW Talyn, Mobil 1 does make fully synthetics, their full synthetics are pretty much their claim to fame in the racing world. They do make blends, like the oil I run, and high grade conventionals as well but their synthetic is synthetic. Their synthetic line has been tested (in gas motors) to maintain it's original lubrication certs for over 10k miles, where lesser oils like valvoline, havoline, pennzoil... all fall off gradually after about 5.

Ideally we could all run Redline oil, it's pretty much bullet proof, passing testing for over 15k. However it's something like $60 a gallon, so it's prohibitively expensive. Anybody use Lucas oil around here? That company was created by a family owned trucking company who wanted to make a superior oil for their rigs. I've heard good things but never used it... anybody?

 

Yo people look here....Mobil 1 Turbo Diesel Truck Synthetic Motor Oil 5W-40 (1Qt) - OIL44986.......

 

That is the oil I actually had bought sitting on the floor to put in after I got done with my mods this winter. I changed my mind and took it back and got my rotella again. I just decided why change when the rotella has been so good to me? If I were to buy a new car (ya right) I would run it for sure. I run mobil one full syn in my race car and really like it.

I run 3000 miles or so is all on my oil as I work the truck pretty hard. Run motorcraft filter always. Tried motorcraft oil a few years ago and for some reason would use a quart b/w changes. Switched back to rotella and quit using any. Don't know why, just what happened with my truck.