Another bad day

[Orangetxguy]

And the prize goes to OTG..... the first one to get it right!!!!

31 years ago I got paid to go to school, so I could learn that there very thing....I think.


Yeah....they paid me to go to truck driving school. I think. I'm tired.

[Kranky]

GH....the only airline a "trolley bar" or "johnnie bar" activate, is the RED one. The redline only activates the trailer brakes, whether it is a 20 foot trailer or a 53 foot trailer, or 2- 28 foot trailers in tandem. (I think I got that right....I'm tired)


The blue line is only activated by the foot treadle.

Uhhh, No.

Actually the red line supplies air to the trailer when the red knob is pushed in. Also,when the red line is charged, the trailer emergency valve releases the trailer spring brakes. When the red knob is pulled out, the red line is discharged, no more air is supplied from the tractor to the trailer, and the trailer spring brakes are applied.

Regarding the blue line, that is the "service brake" line. Anytime the red knob is pushed in and the trailer is charged, stepping on the treadle OR pulling the "Johnny Bar" will send the appropriate amount of air pressure thru the blue line to actuate the trailer relay valve and apply the service brakes on the trailer.

The "Johnny bar" ONLY applies the trailer service brakes, whereas stepping on the treadle applies the tractor service brakes AND the trailer service brakes.

If you don't believe me, push in the red knob, pull your blue gladhand off and apply the johnny bar, you'll get air from the blue line.. Then step on the treadle and you'll also get air from the blue line. (make sure your tractor parking brakes are applied (yellow knob pulled out)so your truck doesn't roll away while performing this test).

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[mike3fan]

And the prize goes to OTG..... the first one to get it right!!!!

Then you're both wrong imo, pulling the trolley bar activates the blue line applying the brakes and the red button activates the red line providing the air to the trailer releasing the spring brakes and providing air to the trailer.

Pulling the trolley bar will do nothing without the red button pushed in.

[Fredog]

[ssoutlaw]

GH....the only airline a "trolley bar" or "johnnie bar" activate, is the RED one. The redline only activates the trailer brakes, whether it is a 20 foot trailer or a 53 foot trailer, or 2- 28 foot trailers in tandem. (I think I got that right....I'm tired)


The blue line is only activated by the foot treadle.

Your hand brake when pulled down only activates the service line, BLUE!!! All trailer brakes only, no tractor..
Your emergency line, RED only charges the trailer brakes!!!!

[ssoutlaw]

And the prize goes to OTG..... the first one to get it right!!!!

Boy did you get that one wrong....lol

[freebirdrfd]

Your hand brake when pulled down only activates the service line, BLUE!!! All trailer brakes only, no tractor..
Your emergency line, RED only charges the trailer brakes!!!!

Finaly the correct answer.

[ssoutlaw]

Its funny just how many drivers now days really don't know how their equipment works.....lol
GOD save us....lol

[ssoutlaw]

31 years ago I got paid to go to school, so I could learn that there very thing....I think.




Yeah....they paid me to go to truck driving school. I think. I'm tired.

No offense, you need to refund some of their money....lol kidding!!!!

[allan5oh]

My truck does not keep the dash mounted "johnson bar" in place. It is spring loaded and goes back to off position when you release it.

I think all trucks should be like that.

[Orangetxguy]

No offense, you need to refund some of their money....lol kidding!!!!

I dunno dude. I was taught...long before I ever left the ranch, that the "johnnie bar" was good for two things. Checking your brake lights, and holding your truck in place while you held the bar down with your hand, and used the clutch and throttle to get the loaded truck and trailer started on a steep hill.


Once I left the ranch....I was taught to check the brake lights with the "johnnie bar", then once that was complete....never touch it again, that all brake action was with the foot treadle. I have ALWAYS pulled the knobs on the dash to park, so I have never had to worry about the type situation Fredog started this entire post about....a run-away truck and trailer!


Back on the ranch, I was also taught to always shut a truck's engine off, with the brakes set and the transmission in "granny" or "reverse".


1973 was a long time ago.


I am not mechanicly inclined. I don't care what "color" lines are. I just care that they work properly and do not leak. Please forgive me.

[Windwalker]

Its funny just how many drivers now days really don't know how their equipment works.....lol
GOD save us....lol

The thought has crossed my mind many times, that if they tested us on the equipment, and those that flunked would have to sit on the bench, they'd put far more of us out of driving than they will with CSA 2010. The differential lock is another part of the equipment that many do not understand. It does not give them "POSI-REARS". It only means they will have 2 wheels spinning, instead of 1. While it is meant to improve traction, it does not lock the axles.

[Kranky]

The differential lock is another part of the equipment that many do not understand. It does not give them "POSI-REARS". It only means they will have 2 wheels spinning, instead of 1. While it is meant to improve traction, it does not lock the axles.

Actually, that's the "power divider lock" that you're speaking of. It locks the inter axle power divider, and just as you said, instead of having 1 of the 4 drive wheels spinning, you will now have 2 spinning(1 on each drive axle).

A true "differential lock" is available on some tandem rears, this will lock the differentials from side to side when engaged, and when locked in conjunction with the power divider lock, you have all 4 tandem drive wheels locked together. You'll either get unstuck, or all 4 drive wheels will be spinning. Don't try to drive on a hard surface with it all locked up, or steering is next to impossible, since all 4 drive wheels are pushing you straight ahead with no differential action possible.

We have both the power divider locks, and the differential locks on the trucks where I work. Ours are on Meritor rears.

.

[Windwalker]

Actually, that's the "power divider lock" that you're speaking of. It locks the inter axle power divider, and just as you said, instead of having 1 of the 4 drive wheels spinning, you will now have 2 spinning(1 on each drive axle).

A true "differential lock" is available on some tandem rears, this will lock the differentials from side to side when engaged, and when locked in conjunction with the power divider lock, you have all 4 tandem drive wheels locked together. You'll either get unstuck, or all 4 drive wheels will be spinning. Don't try to drive on a hard surface with it all locked up, or steering is next to impossible, since all 4 drive wheels are pushing you straight ahead with no differential action possible.

We have both the power divider locks, and the differential locks on the trucks where I work. Ours are on Meritor rears.

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That would sound like a special application. I know that they have them in the far north in Canada. The vast majority of trucks on the road in this country do not have the other switch to lock both sides of the same axle. Only the differential between the two axles. I can imagine the steering would be next to impossible, but I was always told that if you lock both sides of the axles on a bare surface and try to turn, you'll twist off an axle, if you're loaded.

In the past, there has been a few discussions about the inter-axle differential lock. More than a couple of people have been under the wrong impression about them.

[Kranky]

That would sound like a special application.

Dump trucks and heavy haul semi tractors.

I know that they have them in the far north in Canada. The vast majority of trucks on the road in this country do not have the other switch to lock both sides of the same axle. Only the differential between the two axles. I can imagine the steering would be next to impossible, but I was always told that if you lock both sides of the axles on a bare surface and try to turn, you'll twist off an axle, if you're loaded.

Yup. Something has to give!

In the past, there has been a few discussions about the inter-axle differential lock. More than a couple of people have been under the wrong impression about them.

For those that may have questions,here's a PDF explaining the whole thing, inter axle differential, driver controlled diff lock etc.

http://www.meritorhvs.com/MeritorHVS...nts/TP9579.pdf

.

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[Mackman]

My truck does not keep the dash mounted "johnson bar" in place. It is spring loaded and goes back to off position when you release it.

I think all trucks should be like that.

That wouldnt be good in a dump truck when your being pushed by the paver i use it all the time for that.

[Kranky]

That wouldnt be good in a dump truck when your being pushed by the paver i use it all the time for that.

Aw C'mon, there's no better "entertainment" than watching the paver crew go ballistic as you roll out of the hopper and dump a couple yards of mix in front of the paver!!!!

[Mackman]

Aw C'mon, there's no better "entertainment" than watching the paver crew go ballistic as you roll out of the hopper and dump a couple yards of mix in front of the paver!!!!

Then can go crazy when you roll out of the paver LOL.


I was on a job about 5 months ago and one of the drivers never dumped in a paver before. He rolled out like 3 times so the gave up on tryin to push him. He just dumped in the paver and pulled up for the rest of the load. After he was empty they sign him out and told him not to come back intill he knows what he is doing lol.

[Fredog]

Aw C'mon, there's no better "entertainment" than watching the paver crew go ballistic as you roll out of the hopper and dump a couple yards of mix in front of the paver!!!!

except when you forget to let the bed down and pull away and tear the rubber flap off the spreader