Brake Question (1 Viewer)
- Thread starter racevws
- Start date
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I can't lock up my 33's in the dry or activate the ABS. I stop very well though. ABS activates in rain and snow for me.
Unplug the ABS fuse, then do that on the brakes. Should be able to lock up all.
Yes, you may be having a booster issue.
Yes, you may be having a booster issue.
What size are the tires?
- Thread starter
- #5
Pretty much stock, but 10 ply, so kinda heavy
Dirty Koala
SILVER Star
I eliminated my ABS and put in a manual proportioning valve...can lock up my 37's whenever I want now...and my rig is 8k pounds.
- Thread starter
- #8
So I replaced the brake booster check valve and I'm still getting issues braking. When I first stand on the pedal it's really hard and I get very little braking, after about a half second or so, the pedal gets a lot lighter and drops in and the brakes seem to bite. The pedal doesn't go to the floor or anything. I have a spare brake booster and I tried to get the old one out, however I couldn't seem to get it past the intake, especially with the master cylinder still screwed in and pushed out of the way.I tried the adjustment bolt but that didn't seem to help either, although I'm not sure actually did anything to it.
inkpot
SILVER Star
I just went thru this. Brakes worked OK, but they felt slow to react. Found the vacuum check valve did flow air but it did have noticeable resistance to flow. Compared to a spare valve and found to spare OEM valve worked fine and was very free flowing. Tried to swap in the OEM, but no luck as I have aftermarket booster and the hole is not the same size as OEM. Hmmmmm..... ordered a couple of different aftermarket valves from Amazon till I found the right one. Good fit, 100 % free flow for vacuum and 0% flow the other way. No change in brakes, but pedal response has improved dramatically. Higher, firmer, more consistant. Well worth the work and $. Raybestos CV 89000. About $15.
I can lock up my 32ish inch tires and activate ABS on dry pavement but I get into the pedal pretty hard.
It sounds like you are on the right track with your booster. You may want to try the FSM tests which are floating around in recent brake threads here on the forum etc. My understanding of the brake system on these 80s is that if the booster is functioning properly that the brakes are going to feel softer than many may expect even if all is perfect with the system and stopping power is really good. If your booster isn't doing it's job then your pedal will feel heavy / hard but stopping power won't be that great to varying degrees.
It sounds like you are on the right track with your booster. You may want to try the FSM tests which are floating around in recent brake threads here on the forum etc. My understanding of the brake system on these 80s is that if the booster is functioning properly that the brakes are going to feel softer than many may expect even if all is perfect with the system and stopping power is really good. If your booster isn't doing it's job then your pedal will feel heavy / hard but stopping power won't be that great to varying degrees.
- Thread starter
- #11
I did buy a brand new OEM replacement from Toyota. Freaking cost me 45 bucks. I tested it just by putting it on my mouth and blowing and sucking and it seems to be okay. I think there's a valve or something inside of the brake booster. I wonder if it's not actuaiting properly
Dirty Koala
SILVER Star
I put Wilwood manual proportioning valves in both of my 80’s at the same time that I deleted ABS. Much better braking in both trucks now.
Do you have a lift? If so, have you adjusted your LSPV to compensate? As you lift the arm on the LSPV, it allows more braking pressure to the rear brakes.
Malleus
Far west of Siegen
FWIW:
I have one stock 1994 and two stock 1995s. I can lock the brakes on one of the 1995s; the other two have typical mushy 80 series brakes. I bought my first 80 (a 1994) used, with about 30k on when it was about 4 years old. The brakes would put your face on the steering wheel, just like my 1995 (with working brakes). The stock components, when correct, work very well. That said I'm only a couple of weeks into a complete 80 series brake system review and nothing obvious has come to light as of yet, so I can't offer any specific help with your problem, just a thought about where you should expect to wind up.
I have one stock 1994 and two stock 1995s. I can lock the brakes on one of the 1995s; the other two have typical mushy 80 series brakes. I bought my first 80 (a 1994) used, with about 30k on when it was about 4 years old. The brakes would put your face on the steering wheel, just like my 1995 (with working brakes). The stock components, when correct, work very well. That said I'm only a couple of weeks into a complete 80 series brake system review and nothing obvious has come to light as of yet, so I can't offer any specific help with your problem, just a thought about where you should expect to wind up.
- Thread starter
- #18
If you have a write up on the brake system, I would love to go through it. Best of luck.
Malleus
Far west of Siegen
I'm working on it...
I just did the brakes on my '96 80 series. New front brake calipers, new front slotted rotors, Hawk LTS pads, new SS hoses front and rear, rebuilt rear calipers with stock pads. Bled about a half gallon of fluid. With the brakes warm I can lock the fronts/activate ABS on dry pavement.
