Fluids and Lubricants

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With today’s vehicles, proper fluid maintenance is critical to keeping your vehicle in top condition. In fact, proper lubrication is much more important with newer vehicles than those older than ten years. The main reason for this is that components on newer vehicles have much closer tolerances than older vehicles. A lubricant that is too thin or too thick for a given application could result in high heat, causing pre-mature wear, metal-on-metal contact, and ultimately, part failure.

Engine Oil

Of all automotive fluids, engine oil is by far the one with which you should be most familiar. The reason is that engine oil needs to be changed the most often. Engine oil provides a "protective film" between the internal moving parts of the engine. In order to achieve efficient operation of the vehicle's engine, moving engine parts (such as the pistons, cylinders, rods, etc.) are manufactured with "tight" tolerances; they fit together "snugly."

When the engine is running, these parts move against each other at very high speeds creating a tremendous amount of friction. The two main byproducts of friction are heat and wear. With insufficient oil, the parts may "seize" or fail. The primary purpose of engine oil is to minimize the destructive effects of friction during engine operation. Additionally, eninge oil also has cooling characteristics to keep temperatures in check, and contains detergents that keep the engine parts clean.

Unfortunately as the oil lubricates, cools, and cleans, it breaks down and attracts contaminants that can harm the engine if not flushed. Regular oil changes are not only suggested, they are required if you want to keep your vehicle running and in the best mechanical shape possible.

Selecting the Proper Oil

When servicing their own vehicle, many “do it yourselfers” will ask the counterman at the local Auto Parts store what type of oil they should buy for their vehicle. The counterman typically will ask how many miles are on the car, and then give an opinion based on this information. The problem with this recommendation is that the correct type of oil to use could have little, or even nothing, to do with the vehicle mileage. Maintenance and driving habits have a much higher impact on an engine’s condition than does mileage. This is especially true in today’s vehicles, as more and more cars and trucks come onto the market that allow up to 100,000 miles between tune ups.

Instead of asking the opinion of a counterman, go straight to the source: your vehicle’s manufacturer. The owner’s manual for your vehicle will list all the proper weights for a given climate. Select the oil that falls into the climate that matches yours.

To check the engine oil level:

• Start and run the vehicle's engine until normal operating temperature is reached, then turn the engine off.
• Turn the vehicle off and wait approximately 15 minutes to allow the oil to drain back into the oil pan.
• Locate and pull out the engine oil dipstick, and wipe the dipstick with a clean rag.
• Re-insert the dipstick fully, and then pull out.
• Locate the “full” or “add” indicators (marks, holes, lines, etc.) at the end of the dipstick (check your owner’s manual for location and identification, as these marks vary between vehicles).
• If necessary, add oil until the level reaches the “full” mark.

NOTE: A typical vehicle should go between oil changes without the need to add. If you find yourself adding an excessive amount of oil between oil changes, there may be either a leak in the lubrication system, or repairs needed in the engine.

To change the oil:

BE SURE to let the engine cool COMPLETELY before changing the oil. Engine lubricating oil can reach temperatures above 200ºF (93ºC), and can cause serious burns.

• Start by safely raising the vehicle, if necessary, using an approved jack. Once the vehicle is raised, support it in place with correctly rated jack stands. Place an approved oil collection container directly under the oil drain plug. Loosen the drain plug using the correct size socket wrench, until the plug can be easily turned with your fingers.
• Once the plug is loose, remove the plug using your hand. Be sure to keep slight pressure on the plug until all threads have been cleared. Removing the plug this way will keep your socket wrench from getting oil all over it, and will allow you to quickly pull the plug away from the hole once all the threads have been cleared.
• Once most of the oil has drained from the engine, place a new drain plug gasket on the drain plug, and re-install the plug into the oil pan. Be sure to tighten the plug SECURELY.
• Place the oil collection container under the oil filter, and remove the filter with the correct sized oil filter tool.
• Wipe the surface of the engine block (where the oil filter comes into contact with the engine when installed) to remove any dirt, grease or oil.
• Apply a thin coat of fresh oil to the oil filter seal in the new oil filter.
• Fill the new oil filter with fresh oil (Depending on the position of the oil filter when it is installed on the vehicle, this is not always possible).
• Refer to the manufacturer's service manual for your vehicle, install and tighten the oil filter onto engine block with correct amount of twisting force (torque).
• Fill the engine with fresh oil to the correct level.

BE SURE to discard the used oil properly, according to your local city or state regulations.

Automatic Transmission/Transaxle Fluid

Like engine oil, automatic transmission fluid (ATF) should be checked and replaced regularly. The fluid in an automatic transmission not only cools, cleans, and lubricates like engine oil; it also has a direct effect on the shifting characteristics of the transmission.

To check the transmission fluid condition:

• Start and run the vehicle's engine until normal operating temperature is reached, then turn the engine off.
• Pull the transmission dipstick (located near the firewall in most cars) and check the fluid condition. Fresh fluid should be translucent, and is usually red in color. Some darkening is normal, but if the fluid is reddish brown or mustard colored, and has a “burnt” smell, it is worn and should be replaced.

To replace transmission fluid:

Although changing ATF is more complicated than replacing oil, it is still relatively easy, and should only take an hour or two depending on the application. You'll need the service manual for your vehicle, a drain container large enough to catch the drained fluid, and common automotive hand tools (wrenches, pliers, etc.).

• Drain the fluid from the transmission either by loosening the transmission pan (starting at one corner), or by using a hand pump to siphon out the fluid through the dipstick tube.
• Once the fluid has been drained, removing the transmission pan. Clean the transmission pan mounting area on the engine block area of any gasket residue. Also clean gasket residue from the transmission pan.
• Remove the old transmission fluid filter (usually attached by bolts or clips). Retain the clips or bolts for use when installing the new filter. Carefully remove any O-rings or other seals.
• Install a new transmission fluid filter using the clips or bolts from the old filter. BE SURE to replace old O-rings and seals with new items included with the filter.
• Inspect and clean the transmission pan thoroughly. Check the transmission pan for any signs of damage (holes, warping, etc), or evidence of transmission wear, such as metal shavings.
  
  NOTE: A small amount of "clutch dust" may be present. This is considered “normal” in most circumstances. However, if metal shavings are present, the transmission has been damaged and the vehicle may need professional repair.
• Position a new pan gasket on the transmission pan, and install the transmission pan on the transmission.
  
  NOTE: An easy way to hold the gasket in place is to use paper clips. Simply “unwind” the clip until it is loosely in the shape of a V. Slide a pan bolt through the pan and gasket, then slide the modified clip over the threads of the bolt (as close to the gasket as possible) until the clip is snug against the bolt. Repeat for each bolt. Place the transmission pan and gasket up against the transmission, then "finger tighten" the bolts while pulling out the clips.
• After the bolts are "finger tight", use a torque wrench to tighten bolts to proper torque value per the vehicle manufacturer's specifications.
• Refill the transmission using the correct type and amount of fluid as shown in the owner’s manual.
• Recheck the fluid level: With the car on level ground, set the parking brake and place the transmission in “Park” or “Neutral.” Start the engine and idle for a few minutes. Shift the transmission into different positions before returning the lever to “Park” or “Neutral.” Check the fluid level again as described above, and check for leaks.

Engine Coolant

Combustion in a vehicle's engine generates a high amount of heat, often exceeding 2500°F. While heat is a necessary by-product of combustion, prolonged exposure to these excessive temperatures can damage or destroy the engine. The vehicle's coolant system is designed to draw heat from the engine to maintain engine temperature within an accesptable operating range (roughly 200°F/93°C). Although often overlooked, engine coolant must be checked and re-filled regularly.

Although water is an adequate heat dissipater for some uses, it freezes at too high a temperature, and boils at too low a temperature to serve as an adequate coolant. The coolant/antifreeze recommended by your vehicle’s manufacturer increases the water's thermal efficiancy by lowering its freezing point to approximately -34°F (-36°C), and raising its boiling point to approximately 223°F (106°C).

IMPORTANT - HANDLE WITH CARE

Coolant/Antifreeze is very toxic and must be disposed of within state/federal guidelines. Keep coolant/antifreeze out of the reach of children and pets. Avoid contact or coolant/antifreeze with your skin. Gloves are recommended whenever handling coolant/antifreeze. Coolant can also be harmful to painted surfaces. Use care to avoid spilling.

To check the coolant level and condition:

BE SURE to let the engine cool COMPLETELY before checking the cooling system. Engine coolant/antifreeze can reach temperatures above 200ºF (93ºC), and can cause serious burns.

• Be sure the engine has cooled completely. If the vehicle has been driven recently, wait at least 45-60 minutes before attempting to check.
• Remove the radiator cap and inspect the fluid level and color.
  
  Coolant should be replaced in accordance with the manufacturers stated lifespan. Despite retaining its color, coolant can degrade over time and become much less effective than it was originally. An inexpensive tool, called a “hydrometer”, can be purchased at most Auto Parts stores to check the condition of the coolant/antifreeze.

To replace coolant:

BE SURE to let the engine cool COMPLETELY before checking the cooling system. Engine coolant/antifreeze can reach temperatures above 200ºF (93ºC), and can cause serious burns.

DO NOT add plain water to the radiator except in case of emergency. Plain water will reduce cooling system efficiency, and can cause rusting and early failure of the radiator, water pump and/or engine. ALWAYS use the vehicle manufacturer's recommended coolant.

The easiest way to completely remove all coolant is to use a flush kit available at most Auto Parts stores. Follow the kits instructions to flush old coolant from your vehicle. Although not as effective, you can use the following procedure to flush and replace your vehicle's coolant. In either case, you'll need the service manual for your vehicle, a drain container large enough to catch the drained coolant, and common automotive hand tools (wrenches, pliers, etc.).

• Be sure the engine has cooled completely. If the vehicle has been driven recently, wait at least 45-60 minutes before attempting to check.
• Place an approved drain container under the radiator drain valve/stopcock.
• Refer to the service manual for your vehicle. Remove the drain valve on the radiator and drain bolts on the engine (if necessary), and let coolant drain into the drain container.
• Replace the drain bolts and tighten the drain valve. Fill the radiator with clean water, then repeat step 3 until the drained fluid is almost as clear as clean water.
• Tighten the drain valve and replace the engine drain bolts (if necessary).
• Fill the radiator with the vehicle manufacturer's recommended coolant/antifreeze. The water that remained in the heater core, engine block, hoses, etc., following the final draining should give you the proper 50/50 mixture.
• Replace the radiator cap. Start the vehicle, and check for leaks and proper operating temperature.

Brake Fluid

Most people don’t realize how often brake fluid should be replaced, making it the most overlooked maintenance item for a vehicle. This is especially ironic given the safety function of brake fluid and how catastrophic a failure can be. Although the frequency varies between vehicle makes and models, most manufacturers recommend flushing and replacing your vehicle’s brake fluid every 25,000 miles.

To flush brake fluid:

Unfortunately, unless you’re a professional mechanic and have a brake bleeder machine, you’ll need to have assistance when flushing your brake fluid. You'll also need a 2- to 4-foot length of clear vinyl tubing that fits snugly over the bleeder valves, a small drain container, and common automotive hand tools (wrenches, pliers, etc.).

• Siphon the old brake fluid out of the master cylinder, and refill the master cylinder with fresh brake fluid.
• Pour approximately 1-inch of brake fluid into the drain container.
• Place one end of the vinyl tubing over one of the rear brake bleeder valves. Be sure the tubing fits snugly. Place the other end of the tubing in the container of brake fluid. Loosen the bleeder valve.
  
  BE SURE to keep the end of the vinyl tubing (in the drain container) immersed in the brake fluid, or air may be introduced into the vehicle's brake lines.
• Hold the end of the vinyl tubing under the fluid in the drain container. Have your assistant start the engine, and slowly pump the brake pedal.
• After approximately 15 pumps, tighten the bleeder valve, remove the vinyl tubing from the valve, and re-fill master cylinder with fresh fluid.
  
  Fluid will be drained from the master cylinder during the flushing process. Monitor the level of brake fluid in the master cylinder while flushing, and fill with additional fluid, as needed, to maintain adequate fresh fluid.
• Repeat steps 3 through 5 for the front opposite side of the vehicle. Then repeat for the opposite side of the rear, then the opposite side of the front.

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