How well should compression hold the truck?

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xm20k

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You don't want to rely on the parking pawl of an auto to hold it in place either this 1/4" square piece (in red) is what holds my truck in my Powerglide and the spring in green is what keeps it held in place by "wedging" itself between the lever and the other casting in this pic which allows the tab to grab one of the notches in the ring on the planetary.

This image is about 2-3 times the actual size of those parts.
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Radiohead

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Which reminds me, I need to get the parking brake system back up to snuff. I suppose wood chocks would work temporarily, but....
 

Turbo4whl

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Parking brakes have regulations for commercial vehicles in Pennsylvania. Not just medium duty trucks, pickup trucks used in business too. Like so many things, the regulations are blurred. “The brake needs to hold the truck on any hill it is operated on.” There needs to be a test for this, at work I do the test when every an issue is reported. Test, in neutral, hold the truck on a 20 degree hill forward and backward.

This where the cloud in the law is, one statement says hold on a 20% grade, hill. Definition, 45 degree is 100% grade, so a 20% grade is only 9 degree, not 20 degree. Hard to find but I have a road I use with 20 degree angle, very steep!
 

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20% is steep. Most municipalities have a 7% maximum for street grades. 2:1 = 50% = 26.56 degrees, yes, very steep (1 divided by 2 equal 0.50. Moving the decimal two places gets you the percentage. So, 0.50 times 100 equal 50 percent).
Change/Difference in elevation, divided by distance, equals percentage of grade.
 
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DoubleDingo

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Another story:

An underclassman had bought a Jeep Wrangler. He and some buddies drove up on the hill to drink beer and maybe smoke some weed. Not sure, wasn't there, but I guarantee beer was involved with this group. Stopped. Set the brake. Everyone exited. They were standing around BS-ing, when the jeep started rolling away. Down into the aqueduct it went! It was in neutral...

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Radiohead

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20% is steep. Most municipalities have a 7% maximum for street grades. 2:1 = 50% = 26.56 degrees, yes, very steep (1 divided by 2 equal 0.50. Moving the decimal two places gets you the percentage. So, 0.50 times 100 equal 50 percent).
Change/Difference in elevation, divided by distance, equals percentage of grade.
Have one of those 7% grades over on highway 30 not too far from here. I've been fortunate enough to not have to stop on the shoulder and set a brake in anything.

There's always some dingleberry racing up as fast as they can go, stinking up the world with their overheating cat.
 

DoubleDingo

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Have one of those 7% grades over on highway 30 not too far from here. I've been fortunate enough to not have to stop on the shoulder and set a brake in anything.

There's always some dingleberry racing up as fast as they can go, stinking up the world with their overheating cat.
There is a long 6% grade between Bishop and Crowley Lake (Sherwin Grade), and it's brutal. Back in the day there was always a few vehicles pulled over with hoods open and steam coming out. There is a trailer or two along the grade filled with radiator water for those that need to fill their radiators.
 

Terlingueno

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Another story:

An underclassman had bought a Jeep Wrangler. He and some buddies drove up on the hill to drink beer and maybe smoke some weed. Not sure, wasn't there, but I guarantee beer was involved with this group. Stopped. Set the brake. Everyone exited. They were standing around BS-ing, when the jeep started rolling away. Down into the aqueduct it went! It was in neutral...

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Those zany West-Central Inyo County kiddoes...
 

TotalyHucked

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I'm only a couple hours from Mont Eagle and go over it regularly getting to shows in TN, IIRC it's 6% for several miles. Thankfully I've never had an issue and had to stop. Normally I'm one of those dingleberrys going up as fast as I dare cuz it's curvy and fun too lol
 

DoubleDingo

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I'm only a couple hours from Mont Eagle and go over it regularly getting to shows in TN, IIRC it's 6% for several miles. Thankfully I've never had an issue and had to stop. Normally I'm one of those dingleberrys going up as fast as I dare cuz it's curvy and fun too lol
Owning it is half the battle
 

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