Pedal goes 3/4 to the floor before brakes start working

Bleed drums. lpv, front calipers, replaced master new brakes all around e brake is working properly the only thing left to replace would be the brake booster or lpv I’ve ran 2 gallons of brake fluid through the system I’m running out of ideas. does have a 4in lift. bar from lpv bent don’t know the proper stuff for that

 

Throw some pics up. Typically the rear brakes hold the key to proper adjustment

 

This is the rear the e brake is 1 mm before contact

 

Go through this Thread and see if you missed anything.
Did you manually crank the (star wheel) rear brakes out until they just drug/dragged on the drum?
After I did that I got in the cab and gave that Parking Brake a real workout as well.
I think you can clamp off the Vacuum line/assist to the booster and see if it stops giving you assist.
You want to test the LPV, Pull the bar off the axle and strap it up as far as you can (simulating a heavy load), take a test drive. You should have MAX flow to the rears.
CAUTION, do that in a controlled environment for a short drive around the neighborhood!

NICE rust free frame and undercarriage! jelly

 

Can't tel by your pictures...did you install a drop bracket after your lift?



https://www.tundras.com/threads/lspv.135521/

 

I didn't even see that I was staring at that rust free frame and underside of the truck bed.

 

Yup, those giant rear blocks are the root of the problem. Your LSPV rod needs to be relocated as in @w666 post with pics. Remedy that and check back in.

 

While we're at it, is that fresh brake fluid from a recent bleeding, or is your axle seal starting to leak? Have you checked your breather lately?

 

Sorry for the wait I only work it on weekends yes that was fresh brake fluid currently waiting on lpv drop bracket master has no leaks haven’t clamped vacuum line to test booster

 

Are you 100% positive there isn't air trapped at the LSPV? Like, you bled at the LSPV, directly?

What bleeding method are you using? Mashing pedal to floor, vacuum, or pressure bleed/reverse pressure bleed?

You're 100% confident the star adjuster is dialed in correctly, so the tire doesn't spin freely, it has some drag, but not so much it isn't locked up?

 

Yes I bleed the lpv directly using 2 person method yes star cluster is dialed in made it drag a little harder than what I like I’m starting to think booster or lpv drop bracket

 

Without knowing what happened prior to this truck - i.e. ruptured line, leaking bleeder or other event that would introduce air, or a recent brake adjustment, new pads or shoes, any other service you aren't telling us about?

Have you noticed any brake fluid disappearing recently?

I'd say that if you used 2-person method, I suspect you either (A) still have air in the lines, since that's an ineffective way to bleed these trucks esp. with air in the lines or (B) blew out a seal pushing the pedal to the floor, which we've seen before.

The alternative is booster is bad. As others have mentioned in this thread or others, you can check for fluid builup in the booster via the one-way vacuum valve at 10 o'clock(ish) looking from the front bumper, fish something absorbent in that hole.

If you replaced anything at the brake end of things, i.e. wheel cylinders, shoes, pads, etc. then I'd lean towards you didn't adjust shit correctly.

Copy of the FSM is in the megathread sticky 'so you just bought a 1st gen' thread. The 'rear brake adjustment theory' thread is a must-read (all pages) for tips on other things people miss.