I would like to change my RX300 engine for a diesel as I love the car but 15 MPG is not good, any ideas ?


Asked by Oct 06, 2013 at 03:53 PM about the 1999 Lexus RX 300 Base AWD

Question type: Car Customization

1 Answer


To change it to a diesel would be cost prohibitive, plus it would no longer pass any emissions testing. You need to have it checked over, my 99 RX 300 got 20 to 22 on the highway and dropped to 18 around town, the only thing that wasn't stock was a cold air package and iridium spark plugs.

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