Air brake adjustment

It's interesting to see the "protocol" regarding brakes, as we perform all our own servicing - including brake adjustment - ourselves. In nearly 13 years of servicing, we have never had an issue with poor brakes.
On the contrary, anyone who has ever driven our trucks, has commented on the "good" brakes. We adjust them every 1,000km, and use 30/30 boosters throughout and found it to be the only way to go.

I dont think truck brakes are that hard to fix, in some ways easier and cheaper than car brakes. They do get neglected, particularly on trailers.

I was talking to a fleet maintainence manager the other day about this topic and his comments were people are just plain lazy these days and cant be bothered adjusting them.
Something else interesting he said was some of the fleets they look after have the gear through the workshop at xxxx amount of k's which is good but the work profile of the piece of kit isnt considered. One trailer can be doing the north run and be lucky to use the brakes twice in a day. Its buddy trailer can be working down south and the brakes a getting squeezed all day. Some of the trailers that come in at there prescribed service point have next to no brakes.
Lazy wheel attendants.
This is my opinion so im happy to cop flak if you think Im way off the mark.

Basil

I think you're spot on Basil, horses for courses. Seems only logical to apply a service regime that is tailored to your particular application.

Own a scania with a retarder,all problems solved.

No I dont think so, you still need the trailer brakes to stop in a hurry.

I don't understand why there isn't more of an effort to fit trucks with effective brake balancing valves. Every time I watch an unloaded semi do a panic stop (usually at least half a dozen times a day, and mostly due to truck drivers driving trucks like race cars) .. the trailer wheels always lock up and flat-spot the trailer tyres. You only have to see the amount of long, black, dual-tyre skid marks on the roads to see it's a common problem.
I would have thought, in this day and age, it would be a great investment to have a decent, simple, brake proportioning valve, that limits the amount of trailer brake pressure, to help eliminate lock-up. My Holden one-tonner has a simple brake proportioning valve that is just lever-operated by the position of the rear axle relative to the chassis. When unloaded, the lever actuates the valve to reduce pressure to the rear brakes, when you stomp on them. I know it works .. if I stomp on the anchors, the front wheels lock up before the rear. Surely it wouldn't take much to produce a similar, simple mechanical valve, for air braking systems?

JuanTrak
GuddayM8
RE: proportioning valve

FWIW
AFAiK

All Merican trucks have a proportioning valve th@ delivers something like 60% to primemover n 40% to trailer
this way U dont have to use the trolly lever under the steerin wheel
the only time we use the trolley hand valve is when side loading on a hill. Guaranteen to not run away with the engine ideling maintaining air pressure n brakes applied
MT trailers R a problem as there is light load on the wheels n little resistance to the Rd surface = lokup

Cya

[ch9787]

There is a brake proportioning valve available for trailers with air suspension. How it works is when the trailer is empty or part loaded, the valve will supply reduced braking pressure to cater for the load carried. These proportioning valve should be mandatory on all trailers especially dog trailer where on occasions drag an empty trailer with a loaded truck.
Kevin Rudd should put this on the agenda to fully subsidise the supply and fitting of these valves.

the poms have used load sensing valves on truck rear axles for decades, but take them off when exporting to Aus. Don't know what they do for trailers. Maybe it is a case that there is no Aus design rule to cover it?