Rather Diesel

I spent the day under my 1989 4Runner, and I need to replace all the brake lines. I see that Toyota ran two lines to the back of the truck to the propotion valve.

My proportioning valve is one big ball of rust, so it's being junked. Do I still need two lines running to the back?

Thanks
Roy

AH64ID

It can be done so its possible to remove it, you will have TOO much rear braking power if you do this. Do some searching, there are threads on it.

waskillywabbit

iTrader: (-1)

The two hard lines go back there to include the LSPV in the loop for the rear brakes.

Like said above, lots of 411 on this modification....

Rather Diesel

Sorry. I honestly wasn't sure what to use for search words.

Roy

AH64ID

No worries, try different combos, and if you dont have any luck come back and ask...

kyle_22r

one line is a bypass line from the proportioner.

polycrack

This is the only thread i can find about the lspv. thinking of bypassing mine aswell. I figure I could just cap the rear return line to the front and put a summit racing propotion valve in the rear or should i put it up by the MC? it seams the lspv it allways on not providing any braking in the rear. if I lift it (rear) and put it in gear, it takes alot of pressure to stop them at idle in gear (auto). im also wearing down my frt pad fast due to no rear braking force. if this has been done before can someone point me in the right direction. thanks again ps no search results for LSPV

Numbchux

The only thread you could find was 5 years old?


I just wrote a simple how-to on it about a month ago that explains how the system works and how to effectively bypass it:
https://www.yotatech.com/forums/f116...delete-233633/

drew303

Theres a lot of disc brake conversion writeups and discussions... They all involve a manual LSPV more or less

https://www.yotatech.com/forums/f116.../#post50586263

the line back to the front just allows energy sent to rear brakes to be used to help the front.

I use the stock LSPV and a manual with my disc conversion.

KRos_+

https://www.yotatech.com/forums/f116...delete-233633/

thats interesting, and maybe a good idea. I might do it.

https://www.yotatech.com/forums/f120/what-thing-235112/

theres some good pics for reference, what they look like operating properly.

KRos_+

Sorry! I didnt realize how old this post is! OMG haha im a newb.....

Oh well lets keep it goin, Got some good info on here!

bigtex10781

Where can you find a new LSPV without having to go through a dealer and paying $300 for it. I have a 89 Runner that I just bought and the break lines were broke in the back but I have fluid going to the LSPV just not past it. Or is there a way to clean it up.

waskillywabbit

iTrader: (-1)

Look up

:wabbit2:

sixstringslut

You don't want to bypass this unless you like stopping sideways at every intersection. If you have ever driven a early 70's Datsun or Yota, they get pretty wild sometimes.

You can't get any (limited) output because that is what they do. Clean up your old one first, probably OK.

You can get new adjustable ones for around $80 but not near the quality of the rust ball you have.

KRos_+

this thread refuses to die


Theres plenty of info on Yotatech about LSPV's( load sensing proportioning valve). Thats how i learned about them.........and if i can do it anyone can!! (maybe not ^ lol).

Theres a few options. Summit BPV (brake proportioning valve) is only like 40$. But like as stated ^ its not gonna function as well as a factory unit would. But im sure it will be fine. Ive seen ppl on here use them and havent posted any complaints (doesnt mean they dont have any).

You could maybe find one in usable condition from a junkyard. OR pay the dealer prices for a new one. Im sure theres other options as well. Just look at the above posts and links for info. ITs all there. numbchux did a good write up.

http://www.summitracing.com/parts/SUM-G3905/?rtype=10