Garrett GTP38R vs. Stock GTP38 Turbo: What's the Difference for Your 7.3L Power Stroke?

When it comes to turbo upgrades for your 7.3L Power Stroke, you’ll run across two popular Garrett models: the 739619-5004S PowerMax GTP38R and the 702012-5012S Stock Replacement GTP38. While they may look similar at a glance and both carry Garrett's legendary durability, the two are designed for very different goals.

In this post, we’ll dive into what sets them apart and help you decide which one fits your truck’s needs best.

Garrett 739619-5004S – GTP38R PowerMax: The Performance Turbo

If you're looking to increase horsepower and airflow on your 7.3 Power Stroke, the GTP38R PowerMax is where the fun begins.

Key Features:

• Ball Bearing Center Section: Offers quicker spool-up, lower friction, and improved durability over journal bearings.

• 88mm Compressor Wheel: Much larger than stock, this extended-tip compressor wheel pulls in significantly more air.

• Wastegated 1.0 A/R Turbine Housing: Helps manage drive pressure and prevent boost creep while retaining low-end drivability.

• Supports up to 500+ HP (with supporting mods like injectors, tuning, and intake/exhaust upgrades).

• Drop-in Fitment for the 1999.5–2003 7.3L Power Stroke.

Ideal For:

• Tuned trucks with larger injectors

• Towing with extra power

• Weekend warriors and daily drivers wanting extra boost without full race build

Downsides:

• Not recommended for bone-stock setups

• Higher price point due to ball bearings and performance focus

Garrett 702012-5012S – Stock Replacement GTP38: Reliable OEM Refresh

The 702012-5012S turbo is Garrett’s direct stock replacement for the original GTP38 found on 1999.5–2003 7.3L Power Stroke engines.

Key Features:

• Journal Bearing Center Section: Traditional, proven design like the original turbo.

• Standard 80mm Compressor Wheel: Matches the factory turbocharger.

• Includes Pedestal and EBV (Exhaust Back Pressure Valve): Comes as a complete, bolt-in unit.

• OEM-Level Performance: Matches the factory turbo specs for a no-surprises install.

• Plug-and-Play Fitment.

Ideal For:

• Restoring lost power due to a worn-out turbo

• Stock trucks with no major mods

• Budget-conscious repairs

Downsides:

• No performance gain

• Limited airflow for any injector upgrades or tuning

Head-to-Head Comparison

Which Turbo Should You Choose?

Go with the GTP38R PowerMax (739619-5004S) if:

• You're running a tuner and larger injectors

• You want to make more power and spool faster

• You plan to tow heavy or just want stronger performance

Stick with the Stock GTP38 (702012-5012S) if:

• You're replacing a blown or tired turbo on a stock truck

• You're not looking for more power—just reliability

• You want a simple, no-modification install

Final Thoughts

Both of these Garrett turbos are rock-solid options—but built with two totally different end goals in mind. The PowerMax GTP38R is for diesel enthusiasts who want to push the limits of their 7.3L, while the 702012-5012S caters to those who just want their truck running like new again.

No matter which route you go, MSP Diesel Solutions has you covered with in-stock availability and expert support.