7.3 milege dropping

[big315]

Just changed my oil and went to Tampa. I got about 15 mpg. That is down for my Ex 7.3 PSD. I use Royal Purple and have a K & N air filter. I might have gotten hold of some bad diesel but I change the fuel filter pretty often. Can anybody give any suggustions?

Thanks,
John

 

[big315]

Have a signature now.

 

[JimmyDee]

Many will say you will get 1-3 mpg better with a chip if you keep your foot out of it. Could be that the removal of the chip hurt you a bit. Bad fuel is a possibility also.
Jim

 

[kwazyca]

Many will say you will get 1-3 mpg better with a chip if you keep your foot out of it. Could be that the removal of the chip hurt you a bit. Bad fuel is a possibility also.
Jim

12.5-13 MPG without chip.

15.94 MPG with chip.

with a 6.5" lift and 37" tires.

Get an econo tuned chip or re-programmed PCM. (DP Tuner)

Tom

 

[95_stroker]

All good advice guys, but his mileage is dropping for some reason. Unless his mileage dropped only after removal of the chip? Maybe the SD guys can chime in here too, does the FPR screen get clogged and dirty on the fuel filter canister like it does on the older PSD engines? I know that mileage can and will drop off if that is the case.

 

[CHPMustang]

Just changed my oil and went to Tampa. I got about 15 mpg. That is down for my Ex 7.3 PSD. I use Royal Purple and have a K & N air filter. I might have gotten hold of some bad diesel but I change the fuel filter pretty often. Can anybody give any suggustions?

Thanks,
John

Welcome to SDD big315! Great to have you aboard

I've always gotten the best freeway mileage by maintaining the RPM's at 2,000 or under.Around town the shift points I keep in the 1,500-1,750 RPM range for best results.

You have intentions of opening up the intake more and upgrading the exhaust as those two alone will hold our beasts back quite abit.

There's other low cost/free tunes and tweaks you can do to get better MPG's

Bill

 

[bad_bad_bubba]

Welcome Big315

Lets try this a different way....

Big, What kind of milage were you getting before?
Was the drop sudden or over time?
Did you notice the truck running, feeling, or sounding different?
What events could have or did happen just prior to noticing the drop in mpg?
(this would include chip removal, trans fix, filter change, oil change, new tires, ect..)

I think with the answers to these questions we might be a little more help in solving the problem.

 

[DR.billZ]

You check your tire pressure lately? Maybe it's dropped. I run 65-70.

 

[big315]

I have gone to a bigger tire, 2857516, looks great. I was getting 17 before. I have 135,000+ miles on it, and I need all the low cost options I can get my hands on. Football season is here and I am going to see my son play. When his high school takes a road trip, usually it is at least 3+ hours.

 

[Car_nut57]

I have gone to a bigger tire, 2857516, looks great. I was getting 17 before. I have 135,000+ miles on it, and I need all the low cost options I can get my hands on. Football season is here and I am going to see my son play. When his high school takes a road trip, usually it is at least 3+ hours.

You might check fuel pressure.
I picked up a bad load of fuel some time ago and it killed the mileage and performance because it fouled the fuel pressure regulator and the fuel pressure was low as well as fluctuating all over the place.