After the first oil change...

[marcus]

sorry guys i have to comment on this.. i went fr 5w-30 to 5w-30 synthetic.. my mpg went down.. i used to get average of 580-590km on 36 liters now its only 560-570km .. this is during summer so temp is tha same as well as driving habits.. go figure.

[Reddog99]

Originally Posted by marcus

sorry guys i have to comment on this.. i went fr 5w-30 to 5w-30 synthetic.. my mpg went down.. i used to get average of 580-590km on 36 liters now its only 560-570km .. this is during summer so temp is tha same as well as driving habits.. go figure.

I've heard that the Yaris engine is sensitive to oil level being too high (will cause drop in mileage). so double check your oil level and drain off a bit if necessary. FWIW, I changed my oil at 1000 and the mileage dropped 2 mpg. After reading about the too-high symptom, I drained off a little (it was too high) and the mileage came back up.

When I changed my oil to Mobil 1 at 5000 mile, the gas mileage didn't change, but as the engine slowly breaks in, I've noticed that the mileage is slowly improving. Over the last 5000 miles the mileage has improved 3 mpg and I'm averaging over 40 mpg now (as long as I keep my foot out of it).