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Discussion Starter #1
Just did a complete brake job on the front and rear, new everything (everything was a complete rusty mess, things were seized, it was ugly).

Anyway, I put on new wheel cylinders on the rear and wonder if there is anything weird I should know about bleeding those things. I notice the brake lines go to this contraption under the bed and it looks like there is a bleeder valve there. Does that need to be done also?

I use a miti-vac type vacuum pump. I'll probably be doing this alone, so was thinking of turning the brake fluid bottle upside down in the master cylinder so it doesn't run dry. Will this work without making a huge mess? Thanks.
 

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What you saw is the LPV and yes, that does need to be bleed. Also, don't let the brake pedal go all the way to the floor. That can damage the master cylinder. And, start from the furthest point from the master cylinder to the closest.
 

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Discussion Starter #6
Can anyone explain the LPV and at what point I should bleed that? I'm wondering if the rear brakes gets their fluid directly from the LPV, and the LPV gets the fluid from the master. If that is the case, should I bleed the LPV first, then the rear brakes, then the front? Thanks.
 

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Not sure what ist stands for, but the LPV is a device that proportions the amount of brake force according to how much load (weight) you have in the bed. Not 100% sure though. Prolly about 98.4% :)
 

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Load sensing proportioning
and by−pass valve (lsp & bv)
 

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Can anyone explain the LPV and at what point I should bleed that? I'm wondering if the rear brakes gets their fluid directly from the LPV, and the LPV gets the fluid from the master. If that is the case, should I bleed the LPV first, then the rear brakes, then the front? Thanks.
Point to bleed the LPV should be obvious, has the same bleeder valve as the other brakes. As far as order. I've seen some do it (R.R, LPV, LR), others do it (LPV, RR, LR), others do it (RR, LR, LPV). The LPV usually takes longer to get all the bubbles out than the others. I do farthest to closest, so (RR, LPV, LR) and usually after L.R. go back and double check the LPV.

Using a Motiv bleeder or equivalent makes bleeding brakes pretty painless. No worries about the master running dry. It pressurizes the system, so no brake pumping. Being a simple weekend-warrior mechanic, this has made brake jobs 10 times less painful.

/Mike
 

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Discussion Starter #11
Thanks guys, I just wasn't sure if the LPV had to be done before or after the rears. Makes sense to me to go from furthest to closest, RR, LPV, LR, RF, LF.
 
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