Fixing a troublesome LSPV, now works
07-04-2007, 07:50 AM
#1
Registered User
Thread Starter
Join Date: Dec 2006
Posts: 46
Likes: 0
Received 0 Likes
on
0 Posts
Fixing a troublesome LSPV, now works
I am kinda new here so I will say upfront I am no expert but would like to post my problem/fix for others as I have seen much discussion about LSPV and lack of rear brakes.
I will start with the project?
We are putting an 85 4Runner back on the road after sitting for 3 years. The truck was suffering from rear end sag so to save a few $ we had the spring re-arched for about $60, perfect again I might add. This will be my son's first vehicle so safety is the most important thing! Since he had to replace ALL brake components we decided to upgrade to vented, this was the first place he got me to pitch in $.
Anyway we got it done and found that the rear brakes were not doing much at all!
So here is how I fixed it.
I read the FSM over and over and triple checked ever component, bled the system (in the correct order) several times, 3+ qts of fluid at this point. I tried adjusting the spring arm at the axle and still nothing, I took it to the highest point and since the re-arched springs are exactly stock heights it should have been good. Still bad rear brakes so I adjusted them several times, still nothing. So I disconnected the LSPV spring arm and moved the boot so I could see and measure the distance to the piston. To my surprise there was about .050in clearance even at the highest adjustment point (I thought I was making contact before but the boot was causing me to think the spring was touching the piston when it really was not). So I carefully bent the spring rod (I think back to original or very close to it) and adjusted per the initial install procedure in the FSM, should be good now right? WRONG! Still nothing.
Trying to keep from eating away at his budget I decided to try bleeding again, but slightly differently. I disconnected the spring arm again, moved the boot, reinstalled it and then begin bleeding the system. During the bleeding process I moved the spring arm through the pistons range of movement several times, then lowered the arm so it did not contact bled more, then raised it all the way and bled more, then back to moving the piston during the bleeding process. Incidentally I filled the MC three times so it was a lot of fluid run through in this way. We put it all back together, placed it on jack stands (I DO NOT RECOMMEND THIS we blocked the front and tires on both side and placed two sets of stands under the truck with a floor jack) I started it up into third gear and 40mph tapped the brakes and INSTANT LOCK, we are happy now!!! Took it down went for a ride and WOW so much better. Three adjustments later, on a dirt road, and it is just about perfect. Front always locks up before the rear but not to much, wet pavement same and now stops on a dime.
FWIW we even loaded the rear of his truck, about 800+lbs and the brakes still acted as they should so this tells me that the LSPV is working as advertised and I like this better then the aftermarket manual PV for safety and street driving though I am sure the manual option has its merits of-road and with taller lifts.
Sorry for the long post but after reading a lot here and spending many hours on this I figured and hope this might help someone else with rear brake problems.
Some before and after pics, the cleaning is done but still a long way to go.
http://s40.photobucket.com/albums/e2...t=6fc7dc2e.pbw
http://s40.photobucket.com/albums/e2...t=1e0db8b0.pbw
I will start with the project?
We are putting an 85 4Runner back on the road after sitting for 3 years. The truck was suffering from rear end sag so to save a few $ we had the spring re-arched for about $60, perfect again I might add. This will be my son's first vehicle so safety is the most important thing! Since he had to replace ALL brake components we decided to upgrade to vented, this was the first place he got me to pitch in $.
Anyway we got it done and found that the rear brakes were not doing much at all! So here is how I fixed it.
I read the FSM over and over and triple checked ever component, bled the system (in the correct order) several times, 3+ qts of fluid at this point. I tried adjusting the spring arm at the axle and still nothing, I took it to the highest point and since the re-arched springs are exactly stock heights it should have been good. Still bad rear brakes so I adjusted them several times, still nothing. So I disconnected the LSPV spring arm and moved the boot so I could see and measure the distance to the piston. To my surprise there was about .050in clearance even at the highest adjustment point (I thought I was making contact before but the boot was causing me to think the spring was touching the piston when it really was not). So I carefully bent the spring rod (I think back to original or very close to it) and adjusted per the initial install procedure in the FSM, should be good now right? WRONG! Still nothing.
Trying to keep from eating away at his budget I decided to try bleeding again, but slightly differently. I disconnected the spring arm again, moved the boot, reinstalled it and then begin bleeding the system. During the bleeding process I moved the spring arm through the pistons range of movement several times, then lowered the arm so it did not contact bled more, then raised it all the way and bled more, then back to moving the piston during the bleeding process. Incidentally I filled the MC three times so it was a lot of fluid run through in this way. We put it all back together, placed it on jack stands (I DO NOT RECOMMEND THIS we blocked the front and tires on both side and placed two sets of stands under the truck with a floor jack) I started it up into third gear and 40mph tapped the brakes and INSTANT LOCK, we are happy now!!! Took it down went for a ride and WOW so much better. Three adjustments later, on a dirt road, and it is just about perfect. Front always locks up before the rear but not to much, wet pavement same and now stops on a dime.
FWIW we even loaded the rear of his truck, about 800+lbs and the brakes still acted as they should so this tells me that the LSPV is working as advertised and I like this better then the aftermarket manual PV for safety and street driving though I am sure the manual option has its merits of-road and with taller lifts.
Sorry for the long post but after reading a lot here and spending many hours on this I figured and hope this might help someone else with rear brake problems.
Some before and after pics, the cleaning is done but still a long way to go.
http://s40.photobucket.com/albums/e2...t=6fc7dc2e.pbw
http://s40.photobucket.com/albums/e2...t=1e0db8b0.pbw
Last edited by Richredneck989; 07-05-2007 at 04:49 AM.
Thread
Thread Starter
Forum
Replies
Last Post
Suprarossa
99+ Tundra, 00+ Sequoia, 98+ Land Cruiser/LX470
0
07-06-2015 05:21 AM
