Change In MPG
#1
02-12-2018, 09:41 PM
Change In MPG
Evening all,
I use an app called Fuel Buddy to keep track of MPG and expenses for my truck, have noticed a change on my truck since I have change the thermostat. About 4MPG increase, there is no change in the type of driving I am doing still a mix of city and freeway. I have seen this after a tune up but never after a thermostat change.
Not that I am complaining, more wondering about the cause, I change from a 195 degree thermostat to a 180 degree. Could that cause a change? Any other thoughts?
I use an app called Fuel Buddy to keep track of MPG and expenses for my truck, have noticed a change on my truck since I have change the thermostat. About 4MPG increase, there is no change in the type of driving I am doing still a mix of city and freeway. I have seen this after a tune up but never after a thermostat change.
Not that I am complaining, more wondering about the cause, I change from a 195 degree thermostat to a 180 degree. Could that cause a change? Any other thoughts?
#2
02-13-2018, 09:12 AM
#3
02-17-2018, 07:53 AM
What mileage are you actually getting? Any idea what coolant temp it was running before and after? If your old thermostat was stuck open it may have been below 180 to begin with. And I have seen new cheap 180's running closer to 190. I had a 180 in my truck for a while and it definitely got worse mileage.
#4
03-12-2018, 02:29 PM
Morning all,
I waited until I had filled up again, I had been running my parents around so I have been using their SUV and not my Dakota. Still getting with 3/4 of a MPG.
01DEC17 10.34 MPG
21DEC17 10.38 MPG
06JAN18 10.15 MPG
23JAN18 13.23 MPG
12FEB18 13.63 MPG
02MAR18 12.7 MPG
07MAR18 13.09 MPG
The old thermostat is not stuck in the open position, I still have it and can post a picture if any one wants to double check that I looking at it correctly. (I am not and never claimed to be a mechanic.) I am also not sure that the old one was a 195 degree, I assumed that it was as it was installed by the dealership when I had radiator troubles in Florida, but the ex-wife dealt with them. Also with the heat and the humidity they might have gone with a lower temp one.
As you can see right after the thermostat was changed, that was all that was done there was was jump in the MPG.
I waited until I had filled up again, I had been running my parents around so I have been using their SUV and not my Dakota. Still getting with 3/4 of a MPG.
01DEC17 10.34 MPG
21DEC17 10.38 MPG
06JAN18 10.15 MPG
23JAN18 13.23 MPG
12FEB18 13.63 MPG
02MAR18 12.7 MPG
07MAR18 13.09 MPG
The old thermostat is not stuck in the open position, I still have it and can post a picture if any one wants to double check that I looking at it correctly. (I am not and never claimed to be a mechanic.) I am also not sure that the old one was a 195 degree, I assumed that it was as it was installed by the dealership when I had radiator troubles in Florida, but the ex-wife dealt with them. Also with the heat and the humidity they might have gone with a lower temp one.
As you can see right after the thermostat was changed, that was all that was done there was was jump in the MPG.
#5
03-12-2018, 05:58 PM
Your MPG is still quite low, for what you have. My 94 with a 3.9 consistently got 16-17 mpg. (I have gotten better out of V8 Dakotas than that, even)
my 90 3.9 was good for 16 in town/20 on the highway (less power, TBI, pre Magnum than yours)
If all I was gonna get was 10 to 13 MPG I would certainly go back to my 3/4 ton.....
my 90 3.9 was good for 16 in town/20 on the highway (less power, TBI, pre Magnum than yours)
If all I was gonna get was 10 to 13 MPG I would certainly go back to my 3/4 ton.....
#6
03-14-2018, 06:35 PM
still on winter blend (which usually means lower MPG around here) and cold weather so that means longer on open loop before sensor readings take over for PROM chip within computer to determine how much fuel to feed,
on my 92 2wd, I just replaced the transmission with a freshly rebuilt one last weekend, on which I am still dialing in the throttle kickdown cable and such, just topped off the gas tank yesterday (because I found 1 station that had not yet gone from $2.21 to $2.59 along my route home from work) my truck is a V8 with 204K miles on it, and on my last tank I got right at 15. Once summer blend comes out and the engine needs less warmup time I expect that I will be back up around 17ish or slightly better like it was all last summer.... so there is something still wrong with your truck, your area within which you drive, or your driving habits..... I admit mine could be better if I was "nicer" to it as I drive..... I don't take off like a bat out of He11 but I do like to drive faster than I probably should...... there is still room for improvement on your truck....
has it had a COMPLETE tune up in a while? I mean, cap rotor wires plugs air filter, PCV, and gas filter if it is a 93 or older.... (94+ is above the tank, filter is part of fuel pump ***'y) and use good quality parts, no gimmicky crap like Splitfires or E3s etc,,,,
Get the better grade of cap and rotor, the cheap ones are usually aluminum terminals, better ones are brass. Brass lasts longer before getting all burnt up and corroded.
how many miles on yours? Especially being a 6, (odd fire engine) they are harder on timing chains, if yours has 125K or more and has never had that replaced your cam timing is running retarded, (valve timing is separate but related to ignition timing!)
Don't let me scare you, every bit of this stuff is considered MAINTENANCE, NOT parts to wait until your truck leaves you stranded.... they are machines, machines need maintenance.... at this point it is PREVENTATIVE maintenance, which is done to be sure everything is running its best and before it fails......
that complete tuneup, plus belts and hoses, along with dumping every fluid and replenishing with new have been automatic 1st things to do as soon as I bring another vehicle home ever since I have had a drivers license.... only thing I (sometimes) do prior to that tuneup, is stop by the DMV and register it to me. then I have a baseline and know where I stand with a given vehicle.....
on my 92 2wd, I just replaced the transmission with a freshly rebuilt one last weekend, on which I am still dialing in the throttle kickdown cable and such, just topped off the gas tank yesterday (because I found 1 station that had not yet gone from $2.21 to $2.59 along my route home from work) my truck is a V8 with 204K miles on it, and on my last tank I got right at 15. Once summer blend comes out and the engine needs less warmup time I expect that I will be back up around 17ish or slightly better like it was all last summer.... so there is something still wrong with your truck, your area within which you drive, or your driving habits..... I admit mine could be better if I was "nicer" to it as I drive..... I don't take off like a bat out of He11 but I do like to drive faster than I probably should...... there is still room for improvement on your truck....
has it had a COMPLETE tune up in a while? I mean, cap rotor wires plugs air filter, PCV, and gas filter if it is a 93 or older.... (94+ is above the tank, filter is part of fuel pump ***'y) and use good quality parts, no gimmicky crap like Splitfires or E3s etc,,,,
Get the better grade of cap and rotor, the cheap ones are usually aluminum terminals, better ones are brass. Brass lasts longer before getting all burnt up and corroded.
how many miles on yours? Especially being a 6, (odd fire engine) they are harder on timing chains, if yours has 125K or more and has never had that replaced your cam timing is running retarded, (valve timing is separate but related to ignition timing!)
Don't let me scare you, every bit of this stuff is considered MAINTENANCE, NOT parts to wait until your truck leaves you stranded.... they are machines, machines need maintenance.... at this point it is PREVENTATIVE maintenance, which is done to be sure everything is running its best and before it fails......
that complete tuneup, plus belts and hoses, along with dumping every fluid and replenishing with new have been automatic 1st things to do as soon as I bring another vehicle home ever since I have had a drivers license.... only thing I (sometimes) do prior to that tuneup, is stop by the DMV and register it to me. then I have a baseline and know where I stand with a given vehicle.....