What is the recommended oil viscosity for my car?

I have a honda civic with 75k, and I live in El Paso Texas where temperatures are from 30F to 105F. What type of oil should I get? 10W30 10W40?What is the recommended oil viscosity for my car?
I have a 93 civic and I found that the 10W30 synthetic provides the best proformance/ gas milage combination. Make sure you are changing it every 3000 mi down there in the dust.What is the recommended oil viscosity for my car?
Use the manufacturer's recommended oil. Here's why. The lifters in your engine have lube oil holes that are designed to lube the engine with a specific viscosity and molecular size. Oil that is too thick at a given temp cannot lubricate as it should, thus starving the lifter as it is too thick and large to pass through the oiling holes. Trust the manufacturers recommendations, they know what the engine is designed for and why, unlike many 'SHADE-TREE' mechanics.
Both actually cover the ambient temperature range you listed.The10W30 would get a miniscule amount better gas mileage. Get a synthetic blend and go with the 10W30.


Mike
10W30 will do fine although nowadays the manufacturers recommend 5W30 all year round. 5W30 is thinner, therefore flows better through the engine.
The larger the last number the thicker the oil. harder to start in cold weather, but you don't have to worry about that in Texas. So it comes down to the oil channels in your engine. I would recommend 10W30 if you are going to chose between those two. But in the end you should refer to your owners manual to see what they recommend or call a honda dealer..
dont go with 10w40 too thick for that car.


a 5w30 would be ideal if it's warmer, 10w30 if colder!


but do go with a semi-synthetic blend with it having over 75k miles!
when its hot,ust a heavier oil,like 10w40 and 10w30 is ok for when it get colder.