Fits 2015–2019 · Stage 1 and Stage 2 · Mail-in
$2,499
Stage 1
580hp
650lb-ft
From 449 hp / 516 lb-ft stock
The car
For 2017 the facelifted second-generation GL was renamed GLS, a name Mercedes-Benz backs by calling the car the S-Class among SUVs. The GLS550 is the V8 model of that X166, sold for 2017–2019 below the AMG GLS63, with seven seats in three rows.
It keeps a 4.7-liter twin-turbo V8 but pairs it with the 9G-TRONIC nine-speed and 4MATIC with a 50:50 split. Air springs with continuously adjustable dampers are fitted at both axles, and Mercedes-Benz lists a fording depth of 19.7 inches and approach and departure angles of 33 and 27 degrees. It quotes 0–60 mph in 5.2 seconds and a 130 mph limit.
For 2020 the X167 replaced it, and its V8 model became the GLS580, with a 4.0-liter twin-turbo V8 and a 48-volt starter-generator.
Stage 1 is calibrated for the car as it left the factory and takes it from 449 hp and 516 lb-ft to 580 hp and 650 lb-ft on pump-grade fuel. Stage 2 is calibrated for supporting bolt-on modifications and high-octane fuel, for 600 hp and 675 lb-ft. The gearbox has its own controller and torque limits, so the optional TCU tune raises them to match, with sharper shifts and stronger clutch clamping.
Figures & prices
Factory and tuned horsepower and torque from our catalog, with prices for each stage and add-on.
| Model year | Factory | Stage 1 | Stage 2 | Add-ons |
|---|---|---|---|---|
| 2015–2019 | 449 hp / 516 lb-ft | 580 hp / 650 lb-ft $2,499 | 600 hp / 675 lb-ft $2,499 | TCU tune $2,399 |
Tuned figures are estimates, not guarantees. Actual results vary with the car’s condition and modifications, fuel quality and octane, temperature, altitude and the dyno used. See our Terms of Service.
How it works
Choose your year, stage and add-ons and check out securely.
Pack it with your printed order confirmation email and send it to our Phoenix shop.
Within two business days of it arriving.
Return shipping is on us. Reinstall and drive.
FAQ
More answers in our FAQ
Our online catalog lists Stage 1 and Stage 2 tunes for 2015–2019 Mercedes-Benz GLS550 (X166) models. Choose your year at the top of the page; the figures and prices are the same for every year.
Both are the second-generation X166. The GL550, sold until 2016, has a seven-speed automatic; the GLS550 that followed for 2017 has the nine-speed 9G-TRONIC and the facelifted body with the new name. The GL550 has its own page, with its own factory figures.
No. The GLS580 replaced the GLS550 for 2020 on the new X167 generation, with a 4.0-liter twin-turbo V8 and a 48-volt starter-generator in place of the 4.7-liter. It is a different engine in a different SUV.
Stage 1 is calibrated for the car as it left the factory and runs on pump-grade fuel. Stage 2 pairs the calibration with supporting bolt-on modifications such as downpipes and runs on high-octane fuel. On a 2019 car, Stage 1 takes it from 449 hp to 580 hp. Stage 2 takes it to 600 hp.
A TCU tune is available as an add-on ($2,399). It raises the transmission’s torque limits and sharpens the shifts so the gearbox can handle the extra power. Ship your TCU in the same box as your ECU.
More Mercedes-Benz tunes
Contact
Customers across the US order online and mail us their ECU. Our shop is at 952 W Melinda Ln, Suite D in north Phoenix (Deer Valley, 85027), and local owners are welcome to bring their car in. Call, visit or send us an inquiry.