HEAVY HAUL TRUCK & TRAILER SPECS: payloads up to 90,000 LB 

most people would say that you need double frame only when you have a heavy front axle - 18k to 20K. I had a 14.6K front axle on my four axle Mack, and it was too weak for my application (55 ton RGN, total of 8 axles). The front axle was often overloaded. If I were you, I'd spend more money on upgrading the front axle than the frame.

cannot post videos about my work at the construction site.

i installed a valve that equalizes pressure between the truck's last 3 axles. problem solved.

Hey Sergei where did you find this guide?

@@HHTV60 bbbbhhhee