Thinnest transmission oil
Thinner oil decreases friction resistance that the engine must overcome. This leaves you with a bit more mpg and power.
Instructions for mod
See your cars workshop manual for instructions to drain the transmission oil.
Fill the transmission with new thinner oil
Please enter your user name and any relevant data in the table
|User Name||Car Make, Model, Year||Cost of Mod||Time to Perform Mod||MPG Before Mod||MPG After Mod||MPG improvement guess||Instruction Link|
|TomEV||Citicar, electric, 1976||$12 USD||1 Hour||~250 wH/mi||~235 wH/mi||2% to 3%|| Changed transaxle oil from factory recommended 90w gear lube to Pennzoil Synchromesh synthetic manual transmission oil.
NOTE - A lower wH/mi (Watt hour per mile) number signifies better efficiency - just like a low score in golf is better than a high score.
Problems / Consequences of mod
- Additional transmission wear if thinner oil used than car maker specifies.
- Some change in gear mesh sound (qualitative change). Not as metallic sounding - more mellow. (One notices different noises in an EV!)
- No perceptible change in transaxle temperature compared to dino oil.
- This mod will probably void a factory warranty if you use an ultra-thin oil such as Synchromesh for a transaxle/differential.