Rear brake leaver under bed for weight

[stsalvage]

I've seen it on some really old 1 ton and above and seen it on a few 1973--87 chevy and GMC trucks of the 3/4 and 1 ton and flatbed trucks.its a leaver that when you have weight in the back of the bed it increases the pressure for the rear bakes.I just wanted to know where you buy one or the Name of it.Let me know

[harpo231]

I believe that would a pressure lock ,, It's to apply pressure to PB so feet are free for gas and clutch. I think made by Lever-Loc...

[Jeff's bowtie's]

"Load sensing brake valve" I think this is what you are asking about most people bypass them

[jeffahart]

Yes, load valve. Not only bypass... toss! But you can get one at "inline tube" if you want a new one.


j

[Jeff's bowtie's]

Originally Posted by harpo231

I believe that would a pressure lock ,, It's to apply pressure to PB so feet are free for gas and clutch. I think made by Lever-Loc...

I think what you are referring to is the MICO lock installs between master cylinder and wheel brakes!! Push brake pedal down and flip the MICO lock lever and it locks the pressure between valve and brake keeping them drawn

[stsalvage]

The one i saw was under a 1980--87 3/4 or 1 ton chevy truck with a bed.It had a lever that was with in 1 inch of the bed floor under the bed right in the middle of the rear end punkin ether side of the brake lines feed into it a line from your master cylinder would go back to the front to your master.The guy that had it told me it was a GM part for camper models to increase brake load on the rear brakes.

[LockDoc]

Originally Posted by stsalvage

The one i saw was under a 1980--87 3/4 or 1 ton chevy truck with a bed.It had a lever that was with in 1 inch of the bed floor under the bed right in the middle of the rear end punkin ether side of the brake lines feed into it a line from your master cylinder would go back to the front to your master.The guy that had it told me it was a GM part for camper models to increase brake load on the rear brakes.

Yep, that would be what Jeff pictured. Some have a lever and some have a stud sticking out like the one in his picture.....

LockDoc

[HO455]

They were common on 80's & 90's vintage Toyota one ton pickups. I believe they restricted fluid to the rear brakes (similar to the way an adjustable proportioning valve works) when the truck was empty and allowed full pressure when loaded. They fell out out production with the introduction of ABS brakes. They worked pretty well on the trucks at work but the linkages were subject to corrosion failures and then you had problems with the rear brakes locking up.