cross country in the HB

[zm830101]

fixing to take the hardbody cross country. here is my question. i bought the truck used and i am fairly certain that it still has the original 170* thermostat in it. will i see better gas mileage by switching to a 190*? will the truck be a little better off in cold weather with the warmer t-stat?

i have noticed in the summer time the truck gets about 32 mpg and in the winter i'm doing well to get 26 mpg. i realize that oxygenated fuels probably play some role in that but i wonder if temp does too? the truck runs noticeably warmer in the summer months if i trust the accuracy of the stock temp gauge.

also, i run 10-30 in the summer. 5-30 in the winter. anybody ever tried running 5-20 for the sake of fuel economy alone? i figure i can probably get away with it since temps will be quite low. any thoughts?

[zm830101]

nothing huh? well, i guess i will just give the t-stat a shot and see what happens. maybe i'll try the 5-20 at the next oil change since i just changed the oil.

[breadbox]

I have never considered switching t-stats for fuel economy, I didn't know it effected it that much.

You are going crosscountry and it will be mostly highway miles, If you get over 30 MPG you are doing stellar in my opinion.

Where are you driving to and from?

[zm830101]

i'll be driving from the athens ga area to tampa fl area to seattle/tacoma area then back to athens again over the next two weeks.

i put the 195 thermostat in 2 days ago. i drove 98 miles this morning from athens ga to douglasville ga on 3.2 gallons into a direct headwind in 30 - 35 degree temps. tomorrow will be the true test. d'ville to tampa. hopefully i won't be fighting the wind the entire way. we'll see. i suspect the results will be a little better since it is interstate the entire way. i think i hit every redlight between athens and d'ville :/

it only took about 30 minutes to swap out the t-stats so worse case scenario i spend a little time later this month putting the 170 back in. but i figured that if the 30 minutes could save me a chunk of change on a 6000 mile round trip it would be worth it.

as to swapping out the t-stats for fuel efficiency alone, most modern vehicles are equipped from the factory with a 195. an engine is most efficient (from a fueling standpoint) between 195 and 210. the difference is most newer vehicles are equipped with a cooling system that can cope with the extra heat. my initial findings are that the stock temp gauge reads only marginally higher with the 195 and still well within the normal range.

i am keeping a pretty detailed log of my mileage for the trip so i'll report back with what i find over the next couple of days/weeks.

[breadbox]

Nice. Have fun.