My truck is a 2008 F-250 crew cab with a fifth-wheel hitch. I was getting 7.5 miles per gallon on my morning commute into town which is a four mile drive with a mix of steep hills and flat lands. I can only average about 40 mph because of curves and stay on my side of the road. I had reached the point that I was going to park my diesel and start driving my old Jeep because of the poor mileage and the cost of diesel fuel. I never imagined that my mileage would improve to the point that it has according to the on-board calculator which is the same calculator that was reading the 7.5 mpg before I added the cetane booster to it Monday. Today, June 1,2012 I drove the same road that I have driven for the last 30 years and my on-board calculator registered 12.1 mpg. The only thing that has changed is that I added the cetane booster. Monday morning when I made the same trip my on-board calculator showed 7.5. That's all I know, I'm not a diesel mechanic or expert in any way. I learned about cetane booster on this forum and decided to try it, I figured it's only $20 what do I have to lose. Worked for me.

 

I switched to opti lube after running ford additive .check out the ratings on additives ,it seems there is more time between regens except my last tow trip 6 regens in 360 miles!

 

I had my Gear Vendor checked out last week. I brought it to the GV factory in El Cajon, Calif and talked to the owner. He said the problem with towing is the oil in the GV breaks down. The GV and Tranny will handle the load, if you tow disengage the unit and there's no problem. I agree about the break-even cost which as I log highway miles, I'll keep you posted. I'm also going to try the cetane additive and see how it works.

 

Your post Title would make a great bumper sticker or T-Shirt: my truck is a pig on fuel !!!!

 

I'd run a Blackstone analysis on that gear lube and see what they have to say/recommend, although I can't understand for the life of me why GV would make that statement and not have a solution/suggestion to address it...? I'm thinking maybe a HD synthetic gear lube might do the job...what does it normally take? It actually won't handle the load, that's my point, and disengaging it when you're towing is rubbish...it sounds like the GV isn't capable of handling the torque/load/stress of towing which is why they flake when it comes to warrantying its use with vehicles that are towing...blaming the lube/oil is weak sauce...

 

For anyone interested in cetane boost Bell Laboratories makes a product that is just a cetane booster and does not have the cleaning additives and such. Have to purchase it on-line no store outlets that I can finde.

 

I'd be curious if Blackstone could analyze the fluid, since they may not know the elements contained in a GV. I'll do it, if BS can get a accurate analysis.
I agree with your statement about GV. If they make units strong enough for an RV (that weighs <15K) why can't it move a truck with a 12K trailer. I can only speculate about why he said it. Since I don't tow much; I'm not very concerned. The oil is SAE 75W-90 synthetic Gear Oil, change every 10K or every other oil change.


Since I've been on FTE, most people here recommend Diesel Kleen cetane booster, it has additives. It cheap at Wal-Mart.

 

I recently made the trip from San Diego to Dallas (I-8 > I-10 > I-20).
I hand calculated the mileage following Yuma, first time on a long stretch with the GV.
Yuma Az. to Las Cruces NM, 15.8 MPG. adv spd 80
Las Cruces to Midland Tx, 14.4 adv spd 82
Midland to Dallas, 14.4 adv spd

Total MPG Yuma-Dallas. 15.0 (LOM Adv 16.5) Boost was 10-20PSI

From these numbers a GV may not seems worth it. But all hope of better mileage is not lost. The DPF must go!

Parkland, great minds think alike.
Two things to keep in mind, speed limit in West Tx and NM is 80 with lots of long climbs and I was experimenting.
Today I made the run from Dallas to Houston, I got 17.2 MPG, adv spd 74, Boost was 6-12PSI

 

Im really bad with math so anyone got a handy formula to hand calculate the mileage? Im kind of afraid to do it mine already says im getting around 9 empty or loaded

 

Miles driven (between fill ups) divided by gallons used.

 

Once you fill up zero your odometer, next time you fill up divide the gallons of fuel into your mileage showing on the trip odometer.

Example 127 miles driving and you used 10 gallons of fuel = 12.7 MPG

The most important thing is making sure your tank is completely filled up, which means the 1st time the pump nozzle shuts off you can still nurse 2-3 more gallons of fuel into your tank. Yesterday fillup yielded me 16.7 MPG running empty and driving 60-65 MPH.

 

hard to believe ...

 

I usually manage to get 4gallons after the shut off and it is annoying.12-14 mpg combined on the #4setting banks

 

Total BS, I have a F450 with 4:88 rear end and mine is only 2WD with spartan 210 tune, intake, cetane booster on every fill up etc and my truck never has seen better then 14mpg NON towing going 65mph. Usually though you do not see better then 13mpg though even when you baby it. You say your getting 20mpg on a STOCK F450?

 

Ok but for this to be accurate wouldn't we need to know the exact size of our tank and run till we empty? or are we just averaging our mileage still? if that's the case i average about 9 mpg with my bone stock truck. which is pretty much what my lieometer tells me.