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dan1554
08-29-2011, 11:46 AM
So a while back I replaced the rear shoes and bled my entire brake system in hopes to improve braking performance. The shoes really did not need replacement, but I figured 'why not' as I already bought them.

Anyway braking performance is still about the same (maybe a *little* better) when I bought it - OK, but not great. Jamming the pedal down at speed will stop the truck pretty quickly, but will not come close to locking up the wheels.

I'm rolling on 35's, and I understand that the rotational force is much greater on a stock set of brakes. I was curious if anyone out there with big wheels have had any similar issues with decreased braking performance, and what you did if anything to fix it. The previous owner (who built the truck) also complained about decreased performance.

Are there pads out there that anyone can recommend (or rear drum shoes, but I wont hold my breath)? Anything I might be able to do to eek out a little more stopping power?

DaveInDenver
08-29-2011, 12:09 PM
When you rebuilt your rears did you take the self adjusters out, clean them, check that they even works and re-lube? How many clicks does it take to engage the hand brake? Brake dust and rust gums those things up and when they stop working the pedal gets soft due to the excessive travel of the brake cylinders.

The rear drums don't really make all that much difference in actual stopping power, it's the fronts that really make or break (brake) you. But the mini truck adjusters only sorta work, they fall out of adjustment easily and make the pedal and brakes work and feel terrible.

In my truck the best stops have been with plain old organic pads and stock rotors. OTOH, running 35" tires is really putting the brakes beyond their design envelope. I assume you are running the original master, booster and parts, which means you already have a 1" master bore and finned 'V6' calipers and large rear drums. Not much you can to tweak the system, the next step up is T100 brakes with S13 calipers.

dan1554
08-29-2011, 12:36 PM
When you rebuilt your rears did you take the self adjusters out, clean them, check that they even works and re-lube? How many clicks does it take to engage the hand brake? Brake dust and rust gums those things up and when they stop working the pedal gets soft due to the excessive travel of the brake cylinders.

The rear drums don't really make all that much difference in actual stopping power, it's the fronts that really make or break (brake) you. But the mini truck adjusters only sorta work, they fall out of adjustment easily and make the pedal and brakes work and feel terrible.

In my truck the best stops have been with plain old organic pads and stock rotors. OTOH, running 35" tires is really putting the brakes beyond their design envelope. I assume you are running the original master, booster and parts, which means you already have a 1" master bore and finned 'V6' calipers and large rear drums. Not much you can to tweak the system, the next step up is T100 brakes with S13 calipers.

Brake fluid is 100% fresh. Was a lot of sediment in there, so I'm sure it was past-due. The hand brake at first would pull all the way out, but after repeated pulls it has self-adjusted to about 1/3-1/2 of that. Can't recall how many clicks that is, but it feels pretty normal. I really wouldn't trust the hand brake on a steep hill though, no matter how hard I pull it.

All the brake parts appear stock.

The brake pedal itself feels pretty firm, just that when I really stomp on it, I would expect something close to a tire-screeching stop.

Anyway, I'm guessing the big tires are the culprit. Was considering trying the 'yellowstuff' pads up front to see if that would help at all.
http://www.ebcbrakes.com/automotive/yellowstuff_brake_pads/yellowstuff_brake_pads_4000.shtml

rover67
08-29-2011, 01:40 PM
Make sure the brake booster is not leaking (hissing). Mine had started to go bad and I never really thought about it until the braking was just dismal. I kept thinking it was my truck then one day i replaced the booster and it was unreal how much better it stopped.

You can look for aggressive pads for the front, but chances are you won't find anything fancy in terms of shoes for it. Either way like Dave says the drums don't do too much especially in a truck with a lot of weight transfer under braking. I was running Hawk HP Plus pads on the front of my 60 (35's and runner brakes) and loved them, but I went to buy more and they had discontinued that pad for the runners so I went with the Hawk HP super duty pads. The superduty pads kinda suck in comparison. They have good cold bite, but they fade fast. Try the EBC's and let me know what you think, if they offer a pad for the runners I'll try them next time.

But, in the end, the big tires are probably what's causing it to feel the way it does. Can't really change that..

DaveInDenver
08-29-2011, 01:58 PM
Should be about 6~8 clicks to set the hand brake. When your truck was new the hand brake would stall the truck, so there's no reason why it shouldn't work other than we all get lazy and let them go. I'd also be curious your luck with better pads, particular EBC. I've never had much luck with 'performance' pads but get more rotor warping, glazing and squeal. I think the way I drive my truck is too gentle for them to make a positive difference, though.

TIMZTOY
08-29-2011, 07:40 PM
i wouldnt worry about it.. my mini with 35" dont lock them up either. if you have a firm pedal then your good. the rears actually do alot more that you'd think.

also if your running 35's did you adjust your LSPV ? because if you lifted it and did nothing to the LSPV, then the truck thinks that you have no load and will send almot ALL the pressure to the fronts.. either bend down the arm, or get a manual adjust valve.

if your wanting more feadback to the pedal and have it feal firmer get a set of stainless steal hoses. the old hoses get dry and will stretch when pressing the pedal. making the pedal feal soft, and wasting energy expanding the hose, instead of pressing the brakes.

did you resurface your drums ? because if there glazed and/or look like mirrors they there like ice and need to be turned .. (kinda hard to stop on ice).
the proper way to adjust the rear drums are to take one drum off (well say pashenger) and work on the driver side, keep the wheel and tire atached and spin it (truck in nutral). it should only spin about 1/2 - 3/4 of a spin with little effort ( like hand on top of tire and pull down and release). adjust till this is acheaved. you should not have to force anything. you can also do this with the wheel off. if you do it with the wheel off, put at liest one lugnut on to keep the drum center and stright. then the spin should be 1/4 - 1/2. once satisfied. remove the driver side drum and work on the pashenger side the same way...

ttubb
08-30-2011, 07:08 AM
X2 on the LSPV adjustment. X2 on the non-lock up with 35s on a mini. T

dan1554
08-30-2011, 01:26 PM
Brake booster and E-brake seem fine after doing a quick once-over.

It is good to hear from multiple sources that the wheel size is a likely problem. Also got some heavy Detroit iron up front which Im sure does not help either. Did some research on the LSPV and get the feeling that the arm attached to the axle might be missing all together. I'll have to take a look this evening. The truck was mostly built before purchasing it, and while everything seems to be pretty reliable, its almost like I have to research the entire build to fully understand it and what may have been added/missing.

It sounds like there are some things I can do to make it a bit better. Will be looking in to better pads, stainless lines and resurfaced drums. It sounds like the rear wheels will lock up first under braking if the LSPV is completely removed, so I'm almost wondering if some good front pads with a manual proportioning valve would yield more braking power all around.

TIMZTOY
08-30-2011, 05:37 PM
It sounds like there are some things I can do to make it a bit better. Will be looking in to better pads, stainless lines and resurfaced drums. It sounds like the rear wheels will lock up first under braking if the LSPV is completely removed, so I'm almost wondering if some good front pads with a manual proportioning valve would yield more braking power all around.

i wouldnt spent two thought on "better" pads unless you have the cheap "value pads" from the parts stores. get some toyots pads, or good ceramic pads from the parts stores.. the brake system should work just fine when adjusted properlly. and i wouldnt worry about "locking up" because when you lock your tires up, your actually not braking anymore and is less effective. (refer to braking oin ice) need to also make sure that your drums and rotors are not below spec. (it wont matter untill your pads get low)
I'd get a stainless steel hose kit (http://www.trail-gear.com/brakes), and a manual proportioning valve kit (http://www.davezoffroadperformance.com/store/suspension/brakes/adjustable-brake-proportion-valve.html) and also check your drums and rotors for shine-mirror like finish to it. and i deffentlly would not just hook up the rear brakes directlly w/o some sort of valve, unless you replace your master with a chevy style that is valve'd internally and stip all your steel hoses.. (just not worth it)