Tandem placement and turning radius

You said your truck gets serviced twice a year. There are a lot of other components on your truck that require grease other than your 5th wheel. If your truck really does only get greased twice a year then you have a multitude of components that are basically being run dry. Two of those components that aren’t getting greased are the king pins on your steer axle. I would be concerned about operating a truck that is being neglected as yours is because a lot of things appear to be being ignored with your twice a year service schedule. But you’re a million miler and see no issue with running components metal on metal (not just your 5th wheel) so carry on about your day.

 

He’s basically trolling. He said his truck gets serviced twice a year so I brought up other neglected components and he’s trying to twist words to tie what I said back to his statement about a dry 5th wheel when all I was doing was pointing out other parts of the truck that need greased more than twice a year. It’s his classic tactic. He must be bored on a 34 somewhere.

 

no he doesn't know what any of those other components are, how they function or what they do....because no one ever told him....

 

Ever twist your ankle and three days later your back starts hurting? Same idea. An inefficiency in one part of a system ultimately impacts seemingly unrelated areas.

Say with a properly greased 5th wheel it takes XXX pounds of force to take the tractor from straight with the trailer to 10 degrees off set. This force is exerted throughout the steering mechanisms - power steering pump, gear box, pitman arm, drag link, and steering arm. If the 5th wheel is under greased, it will take 110% of XXX pounds of force to achieve the same off set. That means the entire system is working harder than it has to.

If you want to test this in real life find a large paved lot. Put the truck and trailer completely straight and then do a complete circle in the smallest diameter you can. Reposition the truck and trailer in the same spot, disconnect and scrape all the grease off, reconnect and again do a complete circle. You'll find that your turning radius is larger the second time.

 

This will take awhile.
He's going to have to draw alot of diagrams with crayons cuz his trainer never told him this.

 

Yeah, but others might happen upon this thread and it's a valid question. Improperly greased 5th wheels do end up stressing the steering components.

And as much as I hate it, our trucks get a B PM every 75,000 miles and nothing gets greased inbetween. I might not like it, but I'm not the guy paying the bills.

 

Correct. And if a trucker is a company driver for ten years and nobody ever tells him about components on the TRUCK called "King pins", you know what the outcome will be? The trucker won't know what components on the truck called king pins are! We don't magically learn this stuff through osmosis no matter how much experience we have.

 

I never thought of that before. Good point. Interesting