× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network

Automotive HD/Fleet Forum

Professional automotive forum for discussion of heavy-duty trucks, buses and other on- and off-road equipment, and maintenance of automotive fleet vehicles. Discussion topics include fuels and lubricants, hydraulics, performance, on-board diagnostics, powertrain, power distribution, anti-lock braking and stability control systems, and best practices as they relate to heavy duty and fleet maintenance. This forum is for experienced automotive repair professionals only, membership required.

Continue to the description of our next automotive discussion forum, the HVAC Forum.

Recent Automotive Discussions in the Automotive HD/Fleet Forum

Low power
09/24/2025 in the HD/Fleet Forum
[Driveability: 13 International 7300 7.6L] Group, this vehicle has extremely low power, it will only make 5-6 psi of boost pressure. Started out with a 2659 FMI 14, EGR flow rate problem. found EGR cooler restricted so replaced it and EGR valve. No impro...
2000 Freightliner Classic 13spd
09/17/2025 in the HD/Fleet Forum
I have a 2000 Freightliner classic and the issue is the speedometer/odometer doesn't start working until it gets up to 45mph. The speed sensor on the back of the transmission is new and in adjustment and historically the speedometer was replaced 12,000 mi...
Watson Chalin pusher axle
09/13/2025 in the HD/Fleet Forum
[Miscellaneous: 08 Kenworth T800 15.8L] I need info to help diagnose a Watson Chalin pusher axle with auto raise in reverse. I have tried through KW and parts contacted PACCAR for help. Wanted to replace valves but received incorrect ones. Pulled 3 valve...
Truck - bus salvage yards
09/10/2025 in the HD/Fleet Forum
[Miscellaneous: 11 IC Corporation CE School Bus 7.6L] Good day, Here in NJ we live in the "lower rust belt". In recent years I've seen rust and corrosion damage increase very noticeably. My guess is a pronounced increase in brine use plus crappier surfac...
Freightliner/Thomas bus brake lights staying on
09/08/2025 in the HD/Fleet Forum
2009 Freightliner/Thomas SAF-T-Liner C2 (Curved one-piece windshield) All four brake lights at the rear of the bus are staying on. With DDDL software, I can see they are being commanded on. If I unplug the brake light switch, which is part of an air modul...

Automotive Sponsored Discussion Forums