Category — Car Questions

Dear Master Tech Automotive,

What is the difference between 10W30 motor oil and 5W30 motor oil?

Signed,

Confused

Michael Searcy says:

In 10W30 oil, for example, the two numbers (10 and 30) mean it’s a “multiviscosity’ or “multigrade” oil that’s effective over a range of temperature. The first number, 10, is an index that refers to how the oil flows at low temperatures. The second number, 30, refers to how it flows at high temperature. The W means the oil can be used in a winter.

A popular belief is that 5W30 oils were to thin to protect vital engine parts when they get hot and 10W30 caused harder starting on those cold winter morings, but numerous studies have concluded there is essentially no difference between  5W30 oils and their 10W30 brand mates. There is no visable way to tell the difference.

A larger number of automakers now recommend 5W30 as the “preferred” oil and even identify 5W30 on the oil filler cap. However, in most cases the manufacture also provided a chart with various temperature ranges and the acceptable viscosity. In our region the temperature ranges usually allow the use of either 10W30 or 5W30.  Most consumers in the state of Tennessee use the 10W30 because it is the most availabile and usually the least expensive, while maintaining quality and your manufacturer’s warranty.

The purpose of oil is to help protect the engine’s moving parts. But motor oil does much more than lubricate. It helps cool the engine, keeps it clean, prevents corrosion, and reduces friction to improve fuel economy. The worts mistake you can make is to put a single grade oil in an engine that was design to be run on a multigrade oil. Viscosity grade is important to the life of your engine, so be careful. Recommendations vary with the make, engine, and model year of the car, so check your owner’s manual and ask your mechanic for the proper grade of oil.

Instead of doing one big long vacation,I like to do several little mini-vacations spread throughout the year. Prior to going on vacation, I always get a little worried about my car making it all the way to where I’m going and back, so I like to have the guys at Master Tech take a look at my car before I go.

There’s an easy and inexpensive way to do this- just get a premium service oil change for the low, low price of $26.90 and mention to manager Jeff (or Klint if he’s running the desk in Jeff’s absence) that you’re heading out of town, you need a premium service oil change, and you just wanted to make sure everything was looking to be in good shape before you leave. The guys will check out your belts, hoses, tires, and other stuff for you, and you should be good to go.

Now, naturally if you’re having an actual problem you might need a pinpoint diagnosis to see what’s going on, but if your car is running fine and you just want to make sure everything looks OK, the premium service oil change is the way to go.

Incidentally, I just got back from Holiday World. If you’d like to read my thoughts on Holiday World, take a look right over here. Where are you going on vacation, Murfreesboro? Will you go somewhere, near or far, or are you just hanging out around the house?

Watch it, world- my 15 year old is driving. In less than a year he’ll be driving without my supervision. Someone hold me, I’m scared. Now, the kind of car he wants is either a Lancer Evolution (Mitsubishi) or a Volkswagon Jetta. If my wallet didn’t already say no, I have the feeling the technicians at the shop would definitely curb that desire in no time. The general consensus around the shop is to get something that isn’t hard to work on, passes safety standards, and is old, but not so old it’s falling completely apart.

The difference in opinion comes with the size of the car. Some say to get something huge, that way if he’s in an accident, he’s less likely to get hurt. Some say to get something small, so he doesn’t go around hitting things constantly when he’s parking. The only REAL opinion I have is that it has to be something that doesn’t cost a fortune with my insurance company.

So, let’s hear it, readers! What kind of car would you get for a new driver?