Brake loss at high speeds

86.5 7MGE · 10-01-2009, 05:22 PM

Ok so yesterday I was driving back home and as I'm going about 65mph+ I go to slow down and my brakes feel spongy real soft. That morning I didn't have any problems with my brakes. As I'm driving through town this morning I have nice firm brakes about 30mins later when I enter the freeway and I go up to 75mph+ I had to stop quickly when a car cut me off and to my surprise yet again no brakes, as the pedal traveled from about an inch from the floor I could feel the front ones engage and not the rear with loss of pressure. I got out when I stopped and check my fluid level and it's within the specified range between min and max. Can someone help me out on this? Thanks for all your helpful inputs.

2jzmaestro · 10-01-2009, 06:49 PM

it sounds like a busted brake line

Did you ever find any brake fluid under your car?

Have your changed your brake fluid?

Or do you have some crappy brake pads those are bound to screw you over

more information please

86.5 7MGE · 10-01-2009, 07:03 PM

Quote:

Originally Posted by 2jzmaestro

it sounds like a busted brake line

Did you ever find any brake fluid under your car?

Have your changed your brake fluid?

Or do you have some crappy brake pads those are bound to screw you over

more information please

No didn't see any brake fluid under my car. Haven't done anything with the brake fluid except check the level of it maybe two or three times since I purchase the car. I changed out my front brake pads at the begining of this year I believe and haven't got to the rear ones yet. I purchased them from a OReilly's can't remember what the brand was exactly, but can get that once I get home this evening.

Krem · 10-01-2009, 09:15 PM

Something similar happened to me in an old chevy I had... was doin about 75-80 down the highway and when I went to exit, I came up on a 25 mph, u-turn off ramp... I applied the brakes and foot went completely to the floor... I repeated the process a few times and finally built enough pressure to slow for the turn (basically pumped and bled the brakes)... the next morning, I had brake fluid flooding the well of my right front wheel. :\.. busted brake line... The trip home (about 105 miles) was driven at no more than 45 mph, with emergency flashers all the way... had to use my gears to slow and stop the car in the city limits... was not very fun.

If you don't have any cracks in the brake line, I'd have to wonder about your master cylinder.. perhaps it's not pushing the fluid like it should..

2jzmaestro · 10-01-2009, 09:42 PM

use this website and try to see what the exact part is if you can, itll make it much easier for everyone to help you diagnose the problem
http://toyotapartszone.com

hope it helps!!

86.5 7MGE · 10-01-2009, 10:01 PM

Ok thanks Krem and 2jzmaestro for all the input I'll check to see if I have a bad brake line some where n go from there I'll keep you guys updated on the search.

TurboSupera · 10-02-2009, 05:57 PM

How about brake fluid cavitation? It appears that this happens when the car is at higher speeds and when more is required of the brakes, right? The cheapest fix/diagnosis I can think of is to bleed the system with some good quality brake fluid and see if this still happens. Otherwise I think you're looking at a failed brake master cylinder or brake booster.

86.5 7MGE · 10-03-2009, 05:05 AM

Ok I'll look into that thanks

86.5 7MGE · 10-03-2009, 11:37 PM

Quote:

Originally Posted by 2jzmaestro

it sounds like a busted brake line

Did you ever find any brake fluid under your car?

Have your changed your brake fluid?

Or do you have some crappy brake pads those are bound to screw you over

more information please

The brake pads that I put on in the front are Raybestos; I'm going to put some on the the back and check my lines for holes, and my caliapers to see if they need to be replaced.

Supra_Newb · 10-04-2009, 06:19 AM

Also, you might want to check out your bleeder valves, I just changed a caliper and break pads for the rear, it freakin sucked and finally when I got done, my breaks would go right to the floor occasionally, turned out i didn't close the valves all the way LOL, sorreh for my stupidity.

10-01-2009, 05:22 PM	#1
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	Brake loss at high speeds Ok so yesterday I was driving back home and as I'm going about 65mph+ I go to slow down and my brakes feel spongy real soft. That morning I didn't have any problems with my brakes. As I'm driving through town this morning I have nice firm brakes about 30mins later when I enter the freeway and I go up to 75mph+ I had to stop quickly when a car cut me off and to my surprise yet again no brakes, as the pedal traveled from about an inch from the floor I could feel the front ones engage and not the rear with loss of pressure. I got out when I stopped and check my fluid level and it's within the specified range between min and max. Can someone help me out on this? Thanks for all your helpful inputs. __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

10-01-2009, 10:01 PM	#6
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	Ok thanks Krem and 2jzmaestro for all the input I'll check to see if I have a bad brake line some where n go from there I'll keep you guys updated on the search. __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

10-03-2009, 05:05 AM	#8
86.5 7MGE 3" Exhaust Join Date: May 2009 Location: Denver Posts: 104	Ok I'll look into that thanks __________________ Cold Air Intake MIZU Aluminum Radiator Ralco RZ Underdrive Pulley NGK Wires and Plugs Hi Flow CAT MR Muffler Super Coil Techna Fit Brake lines Clear Corner Turn Signal Lens Projector Head Lights Evo Fog Lights Evo Body Kit Soon ---> 3'' Exhaust

10-04-2009, 06:19 AM	#10
Supra_Newb Stock Join Date: Oct 2009 Location: Nebraska Posts: 10	Also, you might want to check out your bleeder valves, I just changed a caliper and break pads for the rear, it freakin sucked and finally when I got done, my breaks would go right to the floor occasionally, turned out i didn't close the valves all the way LOL, sorreh for my stupidity. __________________ 1989 MKIII 7M-GE Automatic

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
My brake lights are stuck on. wtf!	Isphius	MKIII Supra	16	09-07-2009 08:48 PM
Maintenance brake and clutch master cylinder fluid	IHateHacks	MKIII Supra	1	04-18-2007 07:15 PM
Wilwood MKIII Rear brake kit	ARZ	Arizona Performance	0	03-16-2007 07:46 AM
87 supra brake lights	ministrytrav	MKIII Supra	4	11-23-2005 08:53 PM

10-01-2009, 06:49 PM	#2
2jzmaestro Stock Join Date: Sep 2009 Location: LOS ANGELES Posts: 25	it sounds like a busted brake line Did you ever find any brake fluid under your car? Have your changed your brake fluid? Or do you have some crappy brake pads those are bound to screw you over more information please

10-01-2009, 09:15 PM	#4
Krem 3" Exhaust Join Date: Sep 2009 Location: Las Vegas Posts: 167	Something similar happened to me in an old chevy I had... was doin about 75-80 down the highway and when I went to exit, I came up on a 25 mph, u-turn off ramp... I applied the brakes and foot went completely to the floor... I repeated the process a few times and finally built enough pressure to slow for the turn (basically pumped and bled the brakes)... the next morning, I had brake fluid flooding the well of my right front wheel. :\.. busted brake line... The trip home (about 105 miles) was driven at no more than 45 mph, with emergency flashers all the way... had to use my gears to slow and stop the car in the city limits... was not very fun. If you don't have any cracks in the brake line, I'd have to wonder about your master cylinder.. perhaps it's not pushing the fluid like it should..

10-01-2009, 09:42 PM	#5
2jzmaestro Stock Join Date: Sep 2009 Location: LOS ANGELES Posts: 25	use this website and try to see what the exact part is if you can, itll make it much easier for everyone to help you diagnose the problem http://toyotapartszone.com hope it helps!!

10-02-2009, 05:57 PM	#7
TurboSupera 3" Exhaust Join Date: Mar 2008 Location: Garden Grove, CA Posts: 106	How about brake fluid cavitation? It appears that this happens when the car is at higher speeds and when more is required of the brakes, right? The cheapest fix/diagnosis I can think of is to bleed the system with some good quality brake fluid and see if this still happens. Otherwise I think you're looking at a failed brake master cylinder or brake booster.