swapped the rear diff fluid and the 5sp tranny fluid to Red Line fluids and saw a 3.7% increase in fuel economy... 18.2 -> 18.88 mpg. I went ahead and picked up some more rear diff fluid for the wifes truck and the Ram...

 

i wonder why that is? will the red line stuff run with the mopar lsd additive? that is if you got the lsd

 

Better lubricating properties of the oil. the less friction you have, the less HP turning the gears takes from the motor.

Also, you wont need the additive if you get the right red line fluid, there is some that comes with it already.

 

another update... for whatever reason, mpg has gone from 18.3 originally in the Dak to 18.8, and now up to 19.1 mpg... no changes in driving habits in the Dak, could be a different formulation in the gas for winter, i'm not sure but just thought i'd update everyone.

 

whats that stuff called and where can i get it. is that like the same stuff as the synthedic royal purple trans fluid?