Hello to all, I just bought a civic, a 2005 EX Special Edition. My question is this, the owners manual and oil cap say to use 5w-20 oil in the car. However I drive on the interstate every day and usually drive around 75 or 80 most of the time, would it be safe to use a higher viscosity oil in my car? Thanks

 

sure, but it will cost a little bit in MPG and in power. like 0-3 hp, and maybe 0-2 mpg. its not much, but its a difference that is there. if it doesnt leak, then just use a quality synthetic and you dont need to change it as often. synthetic lasts about 7-8k, with a filter change halfway. and it lubricates better.