New Therm Stat = Better Mpg

[Strgzr]

My 99 x was getting crappy milage. Temp was only getting to 182 degrees. Put a new NAPA Therm stat rated at 195-200 degrees and WOW. Fuel milage went up significantly. Asked my Dad (Mech) about the 15-20 degree difference and fuel milage and he thought that that small variation can make a significant difference in milage. 18 bucks and a 20 minute installation, I'll take it...Hope this helps others...
Strgzr

 

[Strgzr]

Forgot to mention, the X runs now from 192 to 205 varying. The old one was stuck at 182 after warm up... Oh, 82K miles on the meter...later

 

[Garth]

I did know that. Change thermostat save on gas.

 

[Aquinoheat]

hey my pops recently put a new t-stat in my sport and seemed to have a drop in gas mileage. The Temp needle only reaches at most 1/3 of the guage. i was wondering how you measured it saying it reaches only 182 F. he said it was a 192 t-stat but i think its a 180.

 

[Strgzr]

hey my pops recently put a new t-stat in my sport and seemed to have a drop in gas mileage. The Temp needle only reaches at most 1/3 of the guage. i was wondering how you measured it saying it reaches only 182 F. he said it was a 192 t-stat but i think its a 180.

I have a Scan Tool that gives live readings... Kinda expensive but before, mine only got to 1/3 the way up. Now it is just less than half way. A little higher to represent 20 degrees.

Regards,
Strgzr

 

[spta97]

I've seen it sugguested on the board that you boil the thermostat in a pot of water with a thermometer to see what temp it actually opens at. My 192 from AutoZone was opening in the 185 - 188 range. They are not fool proof.

 

[jayhawkexplorer]

Strgzr, when you had the old (bad) thermostat in, was your heater still working normally, or was the heater air only lukewarm? I think I may have the same issue you had, but my heater still works fine.

 

[jayhawkexplorer]

C'mon Strgzr, where ya at??

 

[Cypher]

Not to take over, but wouldn't changing to a higher temp thermo have negative effects like engine wear?

 

[jayhawkexplorer]

Yes it would. But in this case, the Explorer is designed to run at 192. So putting in the 180 degree stat did nothing but hurt performance.

 

[N2MUDN91]

I think this is a good spot for me to add in.

Last April I changed my thermostat to find that it was bad (seeing as the spring was compressed and open full time). So with the new T-stat in, it warmed up fairly enough, just above the N in NORMAL. Over the summer, it stayed right there, but as it cooled off for winter, the temp. never has came up above inbetween the bottom line and the N. Just about 2 weeks ago I changed it again, and nothing changed. The T-stat I pulled out was fine. I can't figure out why it's not warming up properly. Could my fan clutch be locked in ON position? I dont have the best of heat because the engine isn't warming enough.

Shane

 

[jeff96]

possibly you have the wrong t-stat in your truck N2mudn91, got mine from autozone for 6 bucks.

 

[jayhawkexplorer]

I think this is a good spot for me to add in.

Last April I changed my thermostat to find that it was bad (seeing as the spring was compressed and open full time). So with the new T-stat in, it warmed up fairly enough, just above the N in NORMAL. Over the summer, it stayed right there, but as it cooled off for winter, the temp. never has came up above inbetween the bottom line and the N. Just about 2 weeks ago I changed it again, and nothing changed. The T-stat I pulled out was fine. I can't figure out why it's not warming up properly. Could my fan clutch be locked in ON position? I dont have the best of heat because the engine isn't warming enough.

Shane

It sounds like it may be a heater core Shane. Its an inexpensive enough part, I think less then $50 from O'Reilly. If you do want to change the stat again, get a Fail Safe one from O'Reilly. They're about twice as much but well worth the price. Rock Chalk

 

[huskyfan23]

What about an improper coolant mixture?

 

[00XLS]

I noticed a gain too after changing mine out, the temp gauge would never really climb even to the temp. icon on my gauge but now with the new tstat it goes half up the "normal" range on the gauge and heats up a bit quick too.

 

[jayhawkexplorer]

How did your heater work with the old stat in?

 

[00XLS]

How did your heater work with the old stat in?

Mine? It wasn't that bad, it took longer to heat up. That could be because of old coolant tho?

 

[Four0Sport]

i havnt changed the thermostat in my sport since ive had the truck. the guage never reads above N or O except when i first start in the morning, itll heat up to the M and go right back down. this is tellin me i might need to change it, but my heater works too good. heater is HOT in 5 mins, its a miracle i wont mess with.

 

[N2MUDN91]

How would a heater core cause the motor to run cool? And Ive always used 192 degree t-stats. I dont really ever use my heat over level 2 on the HVAC.

Shane

 

[huskyfan23]

I think your coolant mixture's wrong. Mine was running hot because I didn't add enough water.