Quality ATFs are formulated to balance performance properties. Adding top treats can disrupt the delicate balance of the ATF and result in lower performance. Get the low-down on critical ATF properties here.
ATF Top Treats
It’s easy to convert an unlicensed ATF into a licensed ATF product using a top treat product. Fact or fallacy?
FALLACY! A licensed ATF is properly balanced with components for optimum performance, so the addition of a top-treat, booster, or converter will upset this balance and harm the ATF performance.
The latest fluids supported by automakers are lower in viscosity—6.0 cSt and thinner—to help improve vehicle fuel economy, but historically, they were blended to 7.5 cSt—a thicker viscosity fluid. Viscosity is important because today’s transmissions are calibrated to perform optimally at the viscosity of the recommended fluid. Use of a high viscosity fluid in a low viscosity application creates a loss of fuel economy and results in lubrication starvation, particularly during start-up.
A Highly Friction-Modified ATF improves the performance of your transmission. Fact or fallacy?
FALLACY! Friction modifiers are chemicals added to ATFs to reduce the surface friction of lubricated transmission parts. Typically, these are polar chemical compounds having a high affinity for metal surfaces. Good ATFs are carefully formulated with a balance of friction modifiers designed to prevent sticking in plate clutches and damage to the clutch surfaces. Clutch friction material and friction modifiers are designed together and are OEM-specific.
If too much friction modifier is used, it can lead to glazing on transmission friction plates (below right), which renders clutch plates — and the transmission — ineffective.
Friction modifiers actually reduce torque capacity, which leads to glazing, slipping plates, poor shifts, and increased heat.
A poor quality ATF retards the formation of deposits and varnish due to oxidation. Fact or fallacy?
FALLACY! Oxidation is formed when iron is in contact with oxygen and strong oxidants (acid), especially in the presence of moisture. This causes deposits, varnish and sludge. Poor quality ATFs are prone to more rapid oxidation. The graph below demonstrates the rapid increase in acidity (caused by oxidation) of an ATF with a top treat compared to the lower acidity level of the ATF without a top treat.
A good quality ATF controls oxidation. An inferior ATF can lead to oil oxidation, which creates a chain reaction of issues.
Oxidation stability is vital to preventing sludge formation or deposits that keep the ATF from pumping effectively within the transmission and protecting the entire system.
Improperly formulated ATFs can harm a transmission.Fact or fallacy?
FACT! OEM-licensed ATFs are balanced to deliver protection to ALL transmission parts regardless of material composition (e.g. steel, lead, brass, copper, plastic, etc.). ATF tests ensure that fluid does not interact negatively with any transmission material.
An ATF top treat will not affect the ability of a fluid to prevent the formation of foam. Fact or fallacy?
FALLACY! A number of top treats were tested and shown to increase the fluid’s foaming tendency – despite claims they inhibit foaming! Anti-foam performance is critical to protection of transmission parts, as foam inhibits lubrication and promotes wear. Foam also reduces hydraulic performance and torque transfer, which leads to power loss. Foam also increases the potential for transmission fluid to be force ejected onto a hot engine, creating a fire hazard.
An ATF top treat has no effect on the wear performance of a fluid and protects transmission parts better. Fact or fallacy?
FALLACY! During industry tests, wear resistance of fluids is evaluated under extreme pressure conditions and varying fluid temperatures. Gear tooth face wear is evaluated, as is gear pitting resistance. These tests have proven that ATF top treats actually REDUCE the anti-wear performance of an ATF.
Balanced anti-wear agents in a licensed fluid prevent wear of metal parts under extreme pressure conditions. Transmissions experience gear and bearing failure and reduction in pump efficiency in fluids without them.
Cold Temperature Performance
An ATF top treat has no effect on pumpability of a fluid at cold temperatures. Fact or fallacy?
FALLACY! ATF formulations are complex; their viscosity can change radically in low temperatures if not properly formulated. If an ATF thickens in cold weather, it won’t flow or pump properly and the transmission is subject to friction imbalance, which can lead to vibration or power loss. It can also cause sluggish shifting and excessive heat generation. All this promotes wear of transmission parts. A licensed ATF is carefully formulated to keep the fluid moving through the transmission in cold weather.