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Randy, Auto Specialist
Category: Car
Satisfied Customers: 9838
Experience:  25 Years Experience Automotive Technology.
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whats..regular oil, sythentic blend, and full systhenic

Customer Question

whats the difference between regular oil, sythentic blend, and full systhenic and when should use them?
Submitted: 5 years ago.
Category: Car
Expert:  Randy replied 5 years ago.
Hello! I will assist you!

Your engine oil does two things. Primarily it stops all the metal surfaces in your engine from grinding together and tearing themselves apart from friction, but it also transfers heat away from the combustion cycle. Engine oil must also be able to hold in suspension all the nasty by-products of combustion such as silica (silicon oxide) and acids. Finally, engine oil minimises the exposure to oxygen and thus oxidation at higher temperatures. It does all of these things under tremendous heat and pressure.

This is how to read the numbers. For example 5W40?

As oils heat up, they generally get thinner. Single grade oils get too thin when hot for most modern engines which is where multigrade oil comes in. The idea is simple - use science and physics to prevent the base oil from getting as thin as it would normally do when it gets hot. There's more detail on this later in the page under both viscosity, and SAE ratings. But as a quick primer - the number before the 'W' is the 'cold' viscosity rating of the oil, and the number after the 'W' is the 'hot' viscosity rating. So a 5W40 oil is one which behaves like a 5-rated single grade oil when cold, but doesn't thin any more than a 40-rated single grade oil when hot. The lower the 'winter' number (hence the 'W'), the easier the engine will turn over when starting in cold climates.

A quick guide to the different grades of oil.
Fully SyntheticCharacteristics
Fuel economy savings
Enhances engine performance and power
Ensures engine is protected from wear and deposit build-up
Ensures good cold starting and quick circulation in freezing temperatures
Gets to moving parts of the engine quickly
Better protection
Good protection within the first 10 minutes after starting out
Roughly three times better at reducing engine wear
Increased oil change intervals - don't need to change it quite so often
Basic protection for a variety of engines
Oil needs to be changed more often

Thank You!

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Customer: replied 5 years ago.
How often do you need to change each type of oil?
Expert:  Randy replied 5 years ago.
You should change regular petroleum based oils every 4-5 thousand miles and synthetic every 5-7 thousand miles.Under severe conditions where there is a lot of stop and go.. change regular petroleum based oils every 3000-3500 miles and synthetic every 5 thousand miles.I drive a Toyota 4Runner and change every 7500, very mild driving.