Ask Sam: 5 tips on car fluids

Sam Freij is the Kingdom Maintenance Director at Alissa Holdings. He has over 23 years of automotive experience under his belt. He will be sharing his thoughts with us on numerous automotive topics every week. He looks forward to answering your questions. 

Dear Readers,

This week I would like to bring up a very important maintenance topic focusing on the importance of exchanging fluids in your car (especially your transmission fluid). But first...

A little bit of history...

Manufacturers have always had a suggested service interval for changing fluids and that includes the transmission, whether it is an automatic or manual shift. When automatic transmissions were first introduced, the suggested service interval was about every three years or 50,000 km. The transmission service consisted of draining the fluid from the pan and maybe the torque converter and replacing the filter (most common design in GM & Ford models). This was a realistic time frame interval and service method as the vehicles were very open and did not build up much heat.

Around 1980, the US auto manufacturers downsized the cars for fuel economy and mounted the power train transverse into the area previously reserved for the engine only. As you can imagine, this increased the heat retention in the engine but especially so for the transmission. The demands placed on the transmission fluid have increased exponentially as a result. The unexpected warranty costs from this required a switch to synthetic fluids that can handle the heat better. Even the synthetic fluids and their additive packages fail over time, as evidenced by the number of valve body failures that cease to work properly from gum and varnish deposits inside the transmission case. The image below displays the main areas in a transmission:

General Motors tried an experiment of sealing the transmission and stating that “it was good for lifetime service”, however that failed miserably! What happened was the fluid and additive package failed to keep gum and varnish off critical components like the valve body and clutch packs. This gum and varnish deposits stick to the valves in the valve body and on the clutch assemblies. The valves move sluggishly or become stuck completely resulting in improper operation or a burned up transmission. Clutch packs slip, hang or grab, which burns them up after some very bad shifting problems. These problems can appear in any transmission some with really low mileage.

Most car manufacturers realized that a transmission fluid exchange was needed so they engineered a transmission flush machine for their own vehicles and made it an essential piece of equipment for their dealer network (meaning dealers are required to own it).  Most transmission fluid exchange machines use a bladder type system to hold the new fluid (usually about 16 quarts), the old fluid flowing from the pump to the transmission cooler is interrupted and the equipment inserted into the loop. The old fluid supplies the hydraulic force to exchange the old fluid for the new. Sometimes they supplement the pressure with a low pressure pump. The new fluid is returned to the pan, where it flows through the filter first, then into the pump, valve body, etc.

The response to car manufacturers equipment from the aftermarket equipment manufacturers has been excellent, with tools like the bulky T Tech II and others like Wynns, BG, and Mighty made by White Industries.

My Recommendations on Changing Car Fluids

1.  Do a transmission fluid flush service every 30,000 km 

Most car manufacturers suggest 100,000 km mileage for transmission service. However, it's better to be safe than sorry so it is still a good idea to perform a transmission flush service every 3 years or 50,000 km This could save you a tremendous amount of money and headaches in the long run. If a valve body fails from excessive gum and varnish deposits, the expected cost can easily reach $5000 a transmission requiring replacement. Can be even more!

2. Use only full synthetic fluids for your transmission fluid service

Most older Asian vehicles have shifting problems after a transmission fluid exchange when other fluid types are used. Always check your owners manual or contact your local dealer.

The same servicing standard applies to other fluids such as power steering, radiator coolant, brake fluid plus rear differential fluid if you have a rear wheel drive vehicle.

3. Service the power steering fluids every 30,000 km

Power steering fluid is very critical for the functionality of your steering system, It lubricates the power steering pump and cools your steering gear which steers the front end of your vehicle.

With time and heat the viscosity plummets and the oil base fluid becomes thin and unable to cool your system which leads to cracking in seals and grommets causing expensive leaks.

4. Radiator coolant fluid nowadays can go up to 100,000 km with no problems, thanks to new technologies

Having said that, I recommend you always check your fluids every oil change and make sure fluids are up to standard. You can also ask for a free temperature tolerance test in most workshops or your local dealership.

Last but not least, you will not be able to stop / slow down your vehicle without brake fluid!

5. Flush your brake fluid every 30,000 km

Again the industry tends to lag here, it recommends servicing brake fluid every 60k or based on condition.

This is how you can tell brake fluid's condition; generally contaminated brake fluid is very dark and grimy looking as shown in the image below:

It also may cause a spongy brake petal, but not always. If you have reason to believe that your brake fluid is contaminated, you should definitely have it changed. If there is more than 3% water in your brake fluid, you run the risk of super heating the water causing one or more of your brake lines to explode, bust or simply leak under usage and pressure which apart from being incredibly dangerous is also tremendously expensive to repair. Brake fluid is very hygroscopic, and when exposed to air, it readily absorbs water.

I hope this was useful information and that our little window here at YallaMotor will help you better maintain your vehicle and protect your investment. Send in your questions to [email protected]. 

Wish you all a great weekend. Drive Safe. 

Sam Freij