Question 1

What is TruckDiag Pro?

Accepted Answer

TruckDiag Pro is a free AI-powered diesel truck diagnostic tool that interprets SAE J1939 fault codes (SPN/FMI) and provides step-by-step repair guidance for semi trucks including Freightliner, Peterbilt, Kenworth, Volvo, Mack, and International.

Question 2

Is TruckDiag Pro free?

Accepted Answer

Yes. Free tier includes limited diagnostic queries and full access to 15 diagnostic guides. Premium plans offer unlimited AI chat and repair cost estimates.

Question 3

What trucks does TruckDiag Pro support?

Accepted Answer

All major Class 6-8 trucks: Freightliner Cascadia, Peterbilt 389/579, Kenworth T680/T880, Volvo VNL, Mack Anthem, International LT, Western Star. Engines: Detroit DD13/DD15, Cummins ISX15/X15, PACCAR MX-13, Navistar N13/A26.

Question 4

Does TruckDiag Pro replace a diagnostic scan tool?

Accepted Answer

No. TruckDiag Pro provides AI fault code interpretation and repair guidance. For bi-directional ECU communication (forced regens, parameter resets), you still need a physical tool like OTR Diagnostics or JPRO. TruckDiag Pro helps you understand codes before connecting hardware.

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