Lubrication Information: Automatic Transmission Fluid 101 With HPL

The transmission in your racecar takes a considerable beating between the raw horsepower you try to force through it and having immense pressure applied before the green light drops on each pass. Having a well-built unit will certainly help the transmission’s longevity, but a part of the equation that’s just as important is the fluid you’re using inside that transmission. We got the low-down on automatic transmission fluid (ATF) from Erik Brock at HPL that covers what properties your fluid should have and how HPL’s line of ATF can help your car perform its best.

On the surface, ATF is a distant cousin of engine oil; it lubricates the internal parts of an automatic transmission, and perhaps more importantly transfers power through the torque converter. The role of ATF is more than just that simple breakdown, it keeps the transmission cool while assisting in the process of transferring debris to the filter of the transmission, as well. So, ATF must maintain a balancing act between keeping certain parts cool and lubricated, while fighting unwanted wear, oxidation, and shearing—all while transferring what could potentially be thousands of horsepower through the torque converter.

The fluid you select will have a big impact on the car’s performance and how long the transmission will live between service intervals.

You can get ATF in formulas that use a petroleum oil base as well as a full synthetic blend. The formulation for each type can vary greatly and will change how the fluid behaves inside the transmission. If the mixture isn’t strong enough, it will lead to the clutches inside the transmission slipping at too high of a rate, robbing your car of performance while causing extra wear on transmission parts. The ATF you select needs to have the right formula that protects parts, while not causing the clutches inside the transmission to slip excessively.

ATF fluids also receive a Viscosity Index (VI) rating that indicates how the viscosity of the fluid changes at different temperature levels. A higher viscosity index rating means the fluid is less likely to be affected by big temperature changes.

What To Look For In Automatic Transmission Fluid

Not all ATF is created equal, so shopping based on price for a high-performance application could lead you down the boulevard of parts failures and inconsistency.  The ATF you select needs to be able to stand up to the punishment of the environment it will be placed in, so there are a few things to consider before you purchase and pour.

Boosted cars like BlownZ06 can be very hard on transmissions, so having a fluid that doesn't fail under high-heat or heavy loads is critical.

As the transmission fluid becomes hot, it will change how the transmission and converter will react under power. This will cause your car to not perform as expected or even damage parts in an extreme situation. With that in mind, the type of racing you will be participating in will change the type of fluid you want to consider, according to Brock.

“For a bracket racer, they need to look for a fluid to help them stay as consistent as possible. You want something in a bracket car that has the high VI number and is stable at a higher temperature since they can be exposed to a lot of different temperatures based on the racing. You also want some options when it comes to the fluid weight because some racers will change fluid based on the changing weather conditions to try to keep their consistency,” he says.

Heads-up racing is a whole different world when it comes to ATF selection, and there are even racers who use hydraulic fluid inside their transmissions.  Even though the transmission will still shift when using hydraulic fluid, there are some shortcomings to this — the primary being that these fluids aren’t designed to be exposed to high levels of heat and are prone to oxidation.

“A heads-up car is putting a ton more power through the transmission, so you first need to deal with that. The load alone is trying to destroy everything inside the transmission, and the load is also trying to power through the transmission itself causing the clutches to slip. So you need a fluid that is capable of protecting and lubricating the moving parts, seals, and bearings, but not jeopardizing the clutch’s ability to grip inside the transmission,” Brock explains.

Checking your transmission fluid often should be a part of your maintenance routine to ensure the fluid is doing its job.

Why HPL Automatic Transmission Fluid Is Different

When it came time to start developing their own line of ATF products, HPL started with a fresh design board to create something that would benefit all lovers of horsepower. They came up with a chemical formula from scratch that is totally unique and is fully synthetic. Everything about the ATF products from HPL is grown in-house and is tested to deal with high temperatures, fight corrosion, and resist oxidation in high-performance transmission environments.

“There are a few things our ATF does different; the number one thing is it helps deal with heat. When transmission fluid gets hot it starts to oxidize, and once it begins that process it’s no longer effective while becoming hard on parts. We put a lot of research and development into how to add more heat protection into our fluid without sacrificing in other areas. There are a lot of additives we put in that are very expensive that help to combat the heat. The second thing is the VI number that our fluid has. We have a very high VI number which makes the fluid more stable at temperature, and that is huge for any racer looking to maximize performance,” Brock says.

Besides fighting heat and being stable when things to get warm, the HPL ATF helps keep the internal parts of the transmission safe from debris that comes from clutch wear as a racer beats on the transmission.

“There’s chemistry in the oil that helps to carry the debris and hang on to it until it gets to the filter. If you don’t have that chemistry in the oil it will fall out, won’t make it to the filter, and will end up in places you don’t want it inside your transmission,” Brock explains.

Using the right ATF will keep your transmission happy and lead to better performance on the track.

From a racing standpoint, the HPL ATF presents the greatest value in fighting heat inside the transmission. By reducing the heat levels the transmission is exposed to, the fluid can increase the life of the internal components and that will increase the time the transmission can remain in the car before service is required.

“You won’t be hurting parts if your oil isn’t oxidizing and not holding excessive amounts of heat. By using HPL ATF you can avoid this and not have to worry about sending your transmission in to be repaired for a reason that can be avoided. You’re also changing the way the transmission works because it will be more consistent since it won’t be as hot,” Brock says.

Before you purchase your next case of ATF make sure you look at how hard you’re pushing your transmission and see if you are selecting the right product for the job. HPL’s line of ATF products are designed to deal with all of the things that hurt transmissions in a harsh racing environment.

About the author

Brian Wagner

Spending his childhood at different race tracks around Ohio with his family’s 1967 Nova, Brian developed a true love for drag racing. Brian enjoys anything loud, fast, and fun.
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