Overload of the Day

[Willie B]

Tomorrow afternoon at 2 I will give 16 CDL students information on {Air Disc & Drum brakes}
along with {Driver Etiquette} behind the wheel and away from it while on duty.
All volunteered time.
*
https://www.wwcc.edu/programs/commercial-truck-driving/

I don't see travel across the country in my future, but that is a bit of education I'd like a better understanding of. There is a rudimentary explanation of air brakes in the driver's manual, but not near as in depth as it could be. Compressor, air valve, foot valve wheel cans & the mechanical components at each wheel I have an understanding of. There are half dozen other air components I don't understand.

 

[Northern mb]

I got my CDL before the course was mandatory. I consider myself to be a decent mechanic but the air brake info in the book was quite confusing. I memorized what I needed to pass the test then started driving. After hauling logs in our climate for a couple winters I understood how the whole system worked quite well and I had fixed most parts of it at one time or another

 

[crane operator]

For sale today. $30 . Just a mildly used hitch.

 

[Deere500a]

$30 that's a steal hard to find they keep your trailer in line

 

[Truck Shop]

Only worn on one side.

 

[Tyler d4c]

Only worn on one side.

Flip it!!

 

[Truck Shop]

Flip it!!

That was a out of service hitch--replace before moving.

 

[Tyler d4c]

That was a out of service hitch--replace before moving.

What is the regulatuin on a eye visable wear?

 

[Coaldust]

What is the regulatuin on an eye visable wear?

Falls under 49 CFR 393.71, tow rings.
Simply said, a tow ring is allowed no more than 18-20% wear or 1/8”.

 

[Welder Dave]

How do you wear a pintle hitch that much? Had to be a lot of movement and rubbing or maybe ground down to fit a smaller latch/hook? Wonder what the latch/hook mechanism is like?

 

[Coaldust]

IDK.? The air compensated hitches do a great job of reducing pintle wear. Back in the old days, the worst pintle wear I witnessed was on pole trailers.

Back then, it was still common practice to weld over the worn part of the eye. Then, in the mid-90’s, maybe, FMCSA put a stop to that. Truck Shop will remember when that was.

 

[Truck Shop]

FMCSA put a stop to that.

IIRC 1993. Too many variables with welding effecting integrity in such a crucial area
for it's intended use. That one's life end was more that slightly overdue. High percentage
of trailer kingpins are also a out of service item. Umatilla Ore port of entry scale just loves
ot throw a emphasis inspection on eyes/pintle/kingpin & fifthwheel jaws. Typically they
scratch a line on the bottom of greasy trailer bolster after they have you back against pin
with trailer brakes set then pull ahead, then place it out of service, then hand out a ticket.
Then you call a mobile welding fabricator that specializes in replacing kingpins, then you
spread your cheeks, all taking place in that exact order.

 

[Tyler d4c]

It sounds like I may have a few trailers that need new eyes

 

[Willie B]

IIRC 1993. Too many variables with welding effecting integrity in such a crucial area
for it's intended use. That one's life end was more that slightly overdue. High percentage
of trailer kingpins are also a out of service item. Umatilla Ore port of entry scale just loves
ot throw a emphasis inspection on eyes/pintle/kingpin & fifthwheel jaws. Typically they
scratch a line on the bottom of greasy trailer bolster after they have you back against pin
with trailer brakes set then pull ahead, then place it out of service, then hand out a ticket.
Then you call a mobile welding fabricator that specializes in replacing kingpins, then you
spread your cheeks, all taking place in that exact order.

I've always wondered what they are made of? It doesn't seem reasonable that a ring 1-3/4" thick can handle a 30 ton trailer.
20 years ago an excavator explained: "I buy a 20 ton excavator, it's as big as I can legally haul behind a dump truck."
More recently, I see a lot of 30 ton tag along trailers.
Only pintle I can recall snapping off was 50 years ago, kid I went to school with got his CDL still in high school. His boss blamed him. He argued he wasn't at fault the ring broke off & the chains broke too. Heavy damage to the skidder and trailer. They did fine and fire him, Vermont at the time required you be 21 to drive commercialy.

 

[Truck Shop]

I've always wondered what they are made of?

IIRC--equivalent of 4140, I read some years ago sticks in mind.

 

[DMiller]

Distinct Forged Steel.

 

[Pops52]

I had one break off. Early 90s. It was welded to the front of this shop built stinger dolly to run chains thru. Going thru some curves on hwy 166 east of Santa Maria Ca. A tense moment….

 

[Deere500a]

Ol' excavator had custom fab built lifting eyes all but 1 blue was replaced with 4 rated trailer pintle eyes the abuse they took from the winch & machine not fail was impressive

 

[colson04]

How do you wear a pintle hitch that much? Had to be a lot of movement and rubbing or maybe ground down to fit a smaller latch/hook? Wonder what the latch/hook mechanism is like?

A pintle hitch isn't a very tight fit like a king pin/fifth wheel. A lot of bigger tillage equipment uses forged pintle rings. I've replaced several of these heavy forged rings over the years as they wear, usually on the inner diameter of the ring. I've also replaced draw bars and hammer straps on the tractor side as they wear too.