Using Proper Fluids in Your vehicle
May 31, 2020
Today, Gary Knurek GoodYear is writing about the proper fluids for your vehicle. It's become more complicated with changes in automotive design and manufacturing. It's not that people in Troy are confused as much as they don't realize how much things have changed in recent years.
If you have questions about the fluids in your vehicle, please don't hesitate to stop by Gary Knurek GoodYear. You can find us on 1973 Livernois in Troy, Michigan 48083.
Just give us a call at 248-362-0350.
Let's take engine oil. Twenty or 30 years ago, there were just a handful of different weights of oil. The weight of an oil is a scientific measure of its properties, particularly its viscosity or thickness.
It was common in those days to use a lighter weight oil in the winter when it's cold outside. That way the oil would be able to splash around inside the engine and protect the parts before it was fully warmed up. And a heavier weight oil would be used in the summer. The thicker oil wouldn't thin out too much in the summer heat and vaporize in the engine.
Modern valve trains have become very complicated with more moving parts and small passages than ever before. The valve train is in the top of the engine, so when the vehicle has been turned off for a while, the oil tends to run down to lower areas. That means the valve train parts are vulnerable at start-up, before the oil starts circulating.
So new weights of oil have been introduced to meet the engineering specifications of these newer engines.
Manufacturers are recommending specific weights of oil. The recommendation is often printed on the oil fill cap. It's certainly in the owner's manual. Of course, Gary Knurek GoodYear in Troy can look it up for you.
It's more important than ever to have the correct weight of oil. The wrong weight could actually harm the engine.
Other fluids are also becoming more sophisticated. In the last few years new types of transmission, power brake fluid and coolant have all been introduced for some of the same reasons as for engine oil.
In addition, vehicle manufacturers are now using a wider variety of materials in these systems. Looking at the cooling system as an example, it used to be that the parts were all made out of steel or iron and the hoses were rubber. Now, some parts are plastic, aluminum or other materials.
So the anti-corrosion additives contained in the coolant, or anti-freeze, need to be different in order to protect the different materials used to make the cooling system. If you use the wrong coolant that wasn't formulated to protect your plastic cooling system parts, they could become corroded and fail. And if you're using the wrong coolant, your cooling system won't be covered under warranty. So it's important to use the right coolant and to not mix different types.
Your owner's manual or service advisor at Gary Knurek GoodYear can make sure you're using the right type. You may have heard of universal coolant. Universal, or global, coolant can be added to other types without harmful reactions. That's OK for an emergency top off, but following your manufacturer's recommendation for your vehicle or other auto type is always a safe bet.
In the area of brake fluid, there are a couple of new formulations. It's important to remember that the new ones aren't better than the old ones. They're just different formulations for different vehicles. So if your vehicle calls for DOT 3, using DOT 4 or DOT 5 is not an upgrade. Use the recommended formula.
There are fluid formulations for vehicles with higher mileage. These are special engine oil, transmission fluid and so on that contain additives to condition and restore seals and gaskets in older engines.
They're fine to use as long as they're a variant of the proper fluid. In other words you can use a high mileage engine oil as long as it's also the correct weight recommended by the manufacturer. Same goes for transmission fluid; as long as it's the right type for your transmission.
Gary Knurek GoodYear
1973 Livernois
Troy, Michigan 48083
248-362-0350
Need Service?
More articles from Gary Knurek, Authorized GoodYear Dealer

T for Transmission, T for Trouble (Automatic Transmission Trouble Signs)
October 12, 2025
One of the hardest working components of your vehicle is its transmission, shifting gears up and down when you need it to. The transmission is vital to your vehicle driving properly, and if you start to see signs of problems in it, its best to have them fixed earlier rather than later. (Since ne... More

Don?t Meddle with the Pedal (Brake Caliper Replacement)
October 5, 2025
If you drive a newer vehicle, chances are it has disc brakes, and one of the components of that type of brake is called a brake caliper. The caliper allows the pressure from your foot on the brake pedal to eventually move brake pads against discs in your wheels, which then slow and stop your veh... More

Mileage Headed Downhill? (What Causes Bad Fuel Economy?)
September 28, 2025
Name someone you know who enjoys spending a lot of money on gasoline. Yeah, me neither. Thats because it costs quite a bit to keep fueling your vehicle. One way to save money on gas is to get good fuel economy, and most of todays vehicles are designed to maximize your mileage. But you might f... More