Originally posted by: intogamer
Originally posted by: BoomerD
Not sure what your comment about "those heavy duty air brakes " has to do with it. Actually, air brakes suck if you need to use them much...lose air pressure each time you step on the foot valve (brake pedal) and it takes time to build it back up...
None the less, that sumbich can drive! Definitely not easy to do something like that in a truck-tractor...
well yeah.. but doesn't it fill up quick or how would the truck-tractor in the video work out?
Don't know how the truck was set-up for the vid. Could have had some kind of high-volume compressor installed that is not stock. No idea. Having driven trucks of many kinds over the years, there have been a few times when I had to pull over and let pressure build back up, or risk losing brakes. MOST brake systems have a minimum amount of air pressure needed to release the spring brakes, (automatically apply if the pressure drops below ~ 45 psi) and they will automatically set if the pressure drops below that point. The US DOT has specs that govern the timer permitted for refilling the brake reservoirs, but it's not an x seconds period kind of thing, but rather:
"An air compressor of sufficient capacity to increase air pressure in the supply and service reservoirs
from 85 psi to 100 psi when the engine is operating at the vehicle manufacturer's
maximum recommended r.p.m. within a time, in seconds, determined by the quotient (Actual reservoir capacity × 25) / Required reservoir capacity."
The older the compressor is, usually, the slower it refills the brake reservoirs...
Yes, be nervous when you see older "beat-up" looking trucks on the roadway...they may not be well maintained, and have crappy brakes...
Edited for your edit...they COULD have retrofitted hydraulic or air over hydraulic brakes for that particuar purpose, and I don't know how European trucks are regulated, but I suspect much more stringently than in the US...