Improved Brakes?

[cumminscruiser]

After a long winding downhill I always smell my brakes and it seems like the front brakes are doing all the work. I think there is a porportioning valve for the rear brakes mabey thats not working right. I've never had one apart so I dont know how they work. I am running 35" tires. Almost forgot it's a 85 FJ60.

Any ideas here??

 

[MoGas]

There are 2 proportioning valves. One is right below your brake booster, caled the P&B valve (Proportioning and Bypass) This valve is not adjustable or repairable. There is a proportioning valve for the rear called the LSPV (Load Sensing Proportioning Valve) There should be a 1/4 inch diameter rod that attaches to the axle at one end and the LSPV at the other end.

Did you have a load at the time? Pulling a trailer? When was the last time you pulled the drums and inspected your brakes then adjusted them?

The LSPV adjustment in the Factory Manual is a complex procedure involving weights, scales, and high pressure gauges, usually only required after suspension height adjustments are made. Many have removed the LSPV and installed an adjustable proportioning valve in it's place.

I will scan and post the procedures for both valves shortly.



Dave

 

[MoGas]

Here is the info from the manual:

Dave

 

[cumminscruiser]

Improved brakes

Wow thanks for the pictures from the manual, well looks like the biggest problem is the spring over, the rear brakes "thinks" there is no load. What I dont understand is during heavy braking the car would tilt forward and the proportioning valve would "think" there is just no load.. I would be interested in looking at the adjustable valve you mentioned.

 

[MoGas]

Considering the weight of the 6BT and the spring over, I would probably replace the LSPV with a manually adjustable proportioning valve. If I am empty, a little rear brake, if I am heavy, more rear brake. It takes some testing to get the right proportions.

 

[cumminscruiser]

Improved braking

Sounds like a good idea, my next question is who, what, when, where and why, well is this an after-market porportioning valve? Where can I get one?

 

[ntsqd]

FJ60's don't have the LSPV, only FJ62's. I think that they are a good idea since they compensate for the way that the rig is loaded. It's just that their range of adjustment doesn't seem to work when larger tires are in the mix.

What I've learned from Mud on the topic: When was the last time that the rear brakes were adjusted? If you don't use the parking brake religiously they're probably out of adjustment since the adjusters are driven by the parking brake actuation. Even if you do use the p-brake every time that you park, it still would be a good idea to check the adjustment as junk can build up and cause the mechanism to not work.

Wilwood is pretty much the only game in the US for adjustable proportioning valves. Those that don't have their name on them directly are private labeled wilwood parts. SSB might make their own p-valves, not sure on that one. Kelsey-Hayes used to be the only option, but it has been years since I saw one of their p-valves. Try Summit Racing or Speedway Motors for those.

 

[bjowett]

Have you tried a better brake pad that can handle more heat without buring?

 

[Gifu]

on FJ40's, the big brake upgrade is to use calipers from V6 4Runner (1992 is what I installed). They are 40 MM piston brakes and larger pads.

 

[OlympiaFJ60]

on FJ40's, the big brake upgrade is to use calipers from V6 4Runner (1992 is what I installed). They are 40 MM piston brakes and larger pads.

Works on the 60 too, but that will give more front brake (a good think when trying to stop fast) but the rear brakes need to be manually adjusted every now and again. I try every 10k/twice a year or every other oil change.

 

[MoGas]

Works on the 60 too,

I wonder if that would work on the 62 also?

 

[OlympiaFJ60]

I wonder if that would work on the 62 also?

Yes it would. There is a lot of info on mud. Short story is using around '92 4 Runner calipers and pads. Optional to upgrade to the slightly larger master cylinder too (1" instead of 7/8"), Some grinding of the caliper or 1/4" spacers depending on wheels. I think this mod is getting common as the core charge for the 4runner calipers was twice the caliper cost. Too many coming back to the rebuild with "old" ones in the box I would guess

 

[AndrewP]

80% or so of your braking is in the front brakes anyway, so it makes sense to use the 4Runner calipers there.

Not much you can do in the rear, except to make sure the bellcranks are free and thus keeping the rear brakes adjusted correctly. It seems that for most, they have never freed up the bellcranks, and so the ebrake works poorly and the brakes don't really self adjust.

I actually think the FJ60 rear brakes work very well, but you do have to keep up with the maintenance. 35 inch tires are just hard to stop and are really at the margin of what the stock brakes can handle.

You can consider rear discs, but then you basically loose your e-brake.

 

[cruiseroutfit]

Another vote for the 4Runner calipers, I've been running them on my FJ40 and couldn't be happier.

My recipie for ultimate brakes (using OE parts)

FJ80 non-ABS master cylinder
89'-95' Calipers (utilizing vented rotors of course)
Proportioning valve, deleting the factory prop. valve.
Adjust rear shoes to spec including tuning the p-brake adjustment) and tune the proportining valve through a series of test drives.

 

[cumminscruiser]

Improved Brakes

Am I getting this right? 4Runner front brakes are bigger than FJ60 front brakes? What about FJ62 front calipers?

My rear brakes are good and adjusted correctly. For starters I'll replace the front pads with better quality pads.