Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - Engine efficiency improvement through higher temp thermostat?

8307c4 · 02-25-2014, 01:18 PM

It's funny how over the years the one thing I found with absolute consistency is that nothing, absolutely nothing comes without some sort of side effect.

Anything I do that saves fuel ends up costing me elsewhere.
And in most cases, it costs way more than fuel I ever saved.

In this particular case I learned (especially with trucks) that higher engine temperatures usually results in higher transmission temperatures... The transmission sits right behind and below the engine, a lot of the engine's heat gets transferred to it, the hotter the engine runs, the faster the transmission warms up.

I hope I don't have to get into what happens to an automatic transmission when it gets too hot, but lets just say they quoted me north of $2000 for a rebuild and I am now running a low temp 160F degree thermostat.

02-25-2014, 01:18 PM	#18 (permalink)
8307c4 EcoModding Lurker Join Date: Feb 2008 Location: Virginia, USA Posts: 80 beamer - '91 bmw 318is 90 day: 32 mpg (US) Thanks: 0 Thanked 4 Times in 3 Posts	It's funny how over the years the one thing I found with absolute consistency is that nothing, absolutely nothing comes without some sort of side effect. Anything I do that saves fuel ends up costing me elsewhere. And in most cases, it costs way more than fuel I ever saved. In this particular case I learned (especially with trucks) that higher engine temperatures usually results in higher transmission temperatures... The transmission sits right behind and below the engine, a lot of the engine's heat gets transferred to it, the hotter the engine runs, the faster the transmission warms up. I hope I don't have to get into what happens to an automatic transmission when it gets too hot, but lets just say they quoted me north of $2000 for a rebuild and I am now running a low temp 160F degree thermostat.