If your vehicle calls for Auto-Trak II, using the correct fluid is essential because these transfer cases rely on specific friction characteristics, detergents, and temperature stability that regular ATF does not provide.

Even though ACDelco Auto-Trak II is the official factory fluid, many high-quality aftermarket alternatives can serve as compatible replacements.

GM Auto Trak II Fluid Equivalent

Brand	Product Name	Equivalent to Auto-Trak II?	Typical Application
ACDelco (OEM)	Auto-Trak II Transfer Case Fluid	Official	GM Autotrac transfer cases (NP8, NV246, BW4482)
Valvoline	Valvoline Transfer Case Fluid	Yes	Transfer cases requiring specialized GM-type transfer case fluid
Royal Purple	Royal Purple Synthetic ATF (recommended for transfer cases)	Yes (commonly used)	GM transfer cases needing synthetic ATF-based fluid
AMSOIL	AMSOIL ATF / Fuel-Efficient ATF	Yes (widely used)	Modern GM transfer cases with ATF-compatible specs
Lucas Oil	Lucas Synthetic Multi-Vehicle ATF	Yes	GM transfer cases compatible with Dexron-style ATF
Mobil 1	Mobil 1 Synthetic ATF	Yes (for many models)	Transfer cases that allow Dexron VI–compatible fluid
Castrol	Castrol Transmax ATF	Yes	Transfer cases accepting Dexron-type synthetic ATF
Pentosin	Pentosin ATF 1	Conditional	For Dexron-spec transfer cases where Auto-Trak II is allowed as an option
Red Line	Red Line D6 ATF	Yes	High-performance synthetic ATF users seeking better thermal stability
Motul	Motul Multi ATF	Yes	Transfer cases compatible with multi-vehicle ATF
Fuchs	Fuchs Titan ATF 4400	Yes	Select GM transfer cases using Dexron VI
Havoline	Havoline Multi-Vehicle ATF	Conditional	For Dexron-approved transfer cases
Triax	Triax Multi-Vehicle ATF	Yes	Broad compatibility transfer cases needing synthetic ATF
NAPA / Service Pro	Transfer Case Fluid (Auto-Trak II Compatible)	Yes (labeled for GM)	Cost-effective Auto-Trak II replacement
Carquest	Multi-Vehicle ATF	Conditional	Some models compatible with Dexron VI
O’Reilly / MasterPro	Auto-Trak II Compatible Transfer Case Fluid	Yes	Budget-friendly aftermarket replacement

What Makes a Fluid Equivalent to Auto-Trak II?

Auto-Trak II is not a standard ATF. It is specifically engineered for the clutch-on-demand system used in GM’s Autotrac transfer cases. To be considered an equivalent, a fluid must meet or exceed requirements such as:

1. Correct Friction Characteristics

The clutch packs in the Autotrac system need a certain level of slip and grip to properly engage. Incorrect friction modifiers can cause shudder, binding, or slipping.

2. High Thermal Stability

Transfer cases work under high temperature and rotational stress. Synthetic-based fluids offer better oxidation resistance and cooling.

3. Anti-Wear and Shear Stability

Proper load-carrying protection ensures the chain, bearings, and planetary gears last longer.

4. Compatibility With GM Transfer Case Seals

Some transfer-case seals can swell or degrade when exposed to incompatible ATF types.

5. Cold-Weather Flow

Low-temperature performance is particularly important in northern climates to prevent stiff engagement or whining.

Aftermarket equivalent fluids are engineered to satisfy these same performance features, making them safe options when Auto-Trak II is unavailable.

Should You Use an Aftermarket Alternative?

For most drivers, using a reputable aftermarket equivalent works perfectly fine. High-end synthetic ATF and transfer-case fluids from brands like Valvoline, AMSOIL, Mobil 1, and Royal Purple provide excellent wear protection and longevity.

However, if your transfer case specifically calls for Auto-Trak II in the owner’s manual, using the OEM product is the safest option—especially if you are maintaining a newer GM vehicle still under warranty.

Use OEM Auto-Trak II when:

Your manual explicitly specifies Auto-Trak II
Your GM vehicle still has a powertrain warranty
You’re troubleshooting transfer-case noise or slipping
You want guaranteed matching friction behavior

Use an aftermarket equivalent when:

OEM Auto-Trak II is unavailable
You prefer full synthetic performance upgrades
You’re outside of warranty
You want a more budget-friendly option

Signs You May Be Using the Wrong Transfer-Case Fluid

Using an incompatible fluid can lead to symptoms such as:

Shuddering during 4×4 engagement
Jerky or delayed transfer-case engagement
Humming or whining noises at low speeds
Transfer-case overheating
Binding in tight turns

If you notice any of these signs after changing fluid, drain and refill with Auto-Trak II or a known, verified equivalent.

How Often Should You Change GM Transfer-Case Fluid?

Most GM trucks and SUVs recommend a transfer-case fluid change every 45,000 to 60,000 miles. If you frequently tow, drive off-road, or use 4×4 mode often, consider shorter intervals such as 30,000–40,000 miles.

Fresh fluid prevents:

Chain stretch
Clutch wear
Gear pitting
Overheating
Seal damage

How to Choose the Right Equivalent Fluid

Here’s a simple checklist to help you pick a proper Auto-Trak II replacement:

Check the Label

Look for clear wording such as “For GM Auto-Trak II” or “Compatible with GM transfer cases.”

Verify Synthetic or Multi-Vehicle ATF

Synthetic or multi-vehicle ATF often offers better protection and is widely compatible.

Confirm Compatibility with Your Transfer-Case Model

NP8, NP246, BW4482, and similar cases require fluids with exact friction properties.

Research Real-World Owner Feedback

Many GM truck owners have years of experience using equivalents like AMSOIL, Royal Purple, and Valvoline.

Avoid Traditional Dexron III Unless Listed

Older Dexron III fluids lack the friction behavior required for Auto-Trak II systems unless your manual specifically permits them.

FAQs

What can I use instead of Auto Trak 2?

You can use several high-quality aftermarket transfer-case or synthetic ATF fluids that are engineered to match the friction and thermal properties of GM Auto-Trak II. Common equivalents include Valvoline Transfer Case Fluid, AMSOIL ATF, Royal Purple Synthetic ATF, Mobil 1 Synthetic ATF, Lucas Synthetic Multi-Vehicle ATF, and store-branded “Auto-Trak II Compatible” transfer-case fluids. Always confirm compatibility with your GM transfer case model before substituting.

What is GM Auto Trak II fluid?

GM Auto-Trak II is a specialized blue transfer-case fluid designed specifically for GM Autotrac 4×4 transfer cases. It contains unique friction modifiers, anti-wear additives, and thermal stabilizers that allow the transfer-case clutch packs to properly engage and disengage during automatic 4WD operation. It is not the same as regular ATF and should only be replaced with fluids that explicitly meet its performance requirements.

What color is GM Auto Trak 2 fluid?

GM Auto-Trak II fluid is blue. The distinct color makes it easy to identify leaks and avoid mixing it with red ATF or other transfer-case fluids.

What fluid to use in GM transfer case?

The correct fluid depends on your GM model and transfer-case type. Many modern GM 4×4 vehicles with Autotrac systems require GM Auto-Trak II. Some older or non-Autotrac transfer cases may specify Dexron III, Dexron VI, or a specialized transfer-case fluid listed in the owner’s manual. Always follow the exact fluid specification in your vehicle’s manual, as using the wrong fluid can cause shudder, noise, or premature wear.

Can I use other power steering fluid in my GM car?

Most modern GM vehicles use Dexron-type ATF in the power steering system, not conventional power-steering fluid. However, you should always follow the specification in the manual. Using the wrong power-steering fluid can cause pump noise, leaks, or steering stiffness. Only use a fluid that matches the GM-approved type for your vehicle.

Can I use Dexron III instead of Dexron II?

Yes. Dexron III is generally considered backward compatible with Dexron II. Many fluids marketed as Dexron III/III-H can safely replace Dexron II in older GM transmissions and systems that originally required it. However, always verify compatibility because certain specialized systems, such as GM Autotrac transfer cases, may require Auto-Trak II instead of any Dexron ATF.

Final Thoughts

GM Auto-Trak II is a specialty transfer-case fluid that maintains the performance and reliability of GM’s Autotrac systems. While ACDelco Auto-Trak II remains the safest and most precise option, many high-quality aftermarket alternatives perform exceptionally well when chosen correctly.

Whether you prefer OEM reliability or want a premium synthetic equivalent, the table above gives you a complete list of safe options for replacing or topping off your transfer-case fluid.