Hello,

From a while searching old threads I know this topic has been beat to death, but I couldn't find a consistent enough theme.

Here's my situation:
My truck, over 15 months of ownership, gets an average of 15.9 mpg. Last 90 days it's been closer to 15.0 or less. Application
-It's used for a mix of work and commuting (~17 mi one way, 30 - 60minutes), carries about 300 lbs of cargo on average, once in a while up to ~1,000.
-All driving is EXTREME stop and go.
-All weather is EXTREME heat and humidity (Miami FL). I don't know if that's enough to help a diesel warm up quicker.
-I don't tow anything now.
-MAYBE in the future I'll tow an enclosed trailer with a camaro (7,000#+++), but that's very far off.

There are two 7.3L-PSD F250's with "low" miles available locally for $13,000 (RC/57k) and $13,500 (SC/33k). Both are stripper work trucks, if that matters. They also have a windowless 7.3L E350 with 94k for $11,000, but the elimination of visibility (NOT safe, locally) and that many miles prolly ain't worth $2,000.

Assuming they'll give me the same interest rate as my bank (fat chance on dealer financing, but whatever), I'll save $ on monthly pmt, and hopefully maintenance costs will be the same.

My question is this: given my uses, and the local conditions... will I see a significant increase in MPG? I figured, diesels burn very little fuel at idle ... and I do a LOT of idling.... and down the road, my truck's 4600# tow capacity won't pull ANY production car in an enclosed trailer.

According to www.fuelgaugereport.com, down here, in the past year diesel has been 5 - 13 % more expensive than gas. That means I'd have to get 17 or 18 mpg (13% better MPG) just to RECOUP the extra cost of diesel ... IF diesel stays less than 13 % more expensive than 87 unleaded.

Bottom line: Can I expect 18+ mpg unloaded in nightmare traffic ... or am I sniffing fumes?

Adam

 

Yep, pretty much. You MIGHT, and I mean MIGHT get 18+ mpg running unloaded on the highway for long stretches. Good luck getting that in heavy stop and go traffic. You're looking at around 14-16 mpg in town tops. Some trucks do manage to do slightly better than that, but some get around 10mpg in town. Unless you're requiring the towing capacity based on what you said a diesel isn't really the perfect fit.

 

Average highway MPG @ 72 MPH (2000 RPM) for me is 16.5 MPG, although my max MPG has been 18.2 from Flagstaff, AZ to Havazooo, AZ. 16.5 was on the open highway, no stops, etc. Just cruising on flat ground. Slow it down a bit, and your MPG will go up. Although flying up the Rockies at 3 AM listening to 10 - 15lbs of boost (music to my ears) will net you 14 MPG @ 75ish mph...

 

12 city/ 17 hwy

 

Diesel is also a more expensive fuel than gas as well, make sure to keep that in your calculations. Unless you are towing alot (a gas engine will drink under a load) you won't see much of a benefit by going with that big of a diesel.

 

Sssssh!!! Don't ruin it for me.