Strange Braking Problem....
Thread Starter
Instructor
Joined: Jul 2018
Posts: 216
Likes: 36
From: Frisco, TX
Strange Braking Problem....
Hi All:
'95 6spd; Normally when stopped at a light, if there is any bit of a grade, I'll have to keep my foot on the brake to keep the car from rolling forward or back. But it seems that when it's hot, it feels like the brakes are dragging. Not a lot, but enough to notice. The car will not roll on its own. And you can feel it while coasting to a stop. I used an IR thermometer to take the temp of the rotors after I noticed this. The fronts were around 245 and the rears were about 160. Don't know what's normal. Not racing, just normal city driving. Any ideas??
Thanks,
Nick
'95 6spd; Normally when stopped at a light, if there is any bit of a grade, I'll have to keep my foot on the brake to keep the car from rolling forward or back. But it seems that when it's hot, it feels like the brakes are dragging. Not a lot, but enough to notice. The car will not roll on its own. And you can feel it while coasting to a stop. I used an IR thermometer to take the temp of the rotors after I noticed this. The fronts were around 245 and the rears were about 160. Don't know what's normal. Not racing, just normal city driving. Any ideas??
Thanks,
Nick
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
Not normal, my '95 6spd does the same thing. The brake lines on these cars have been known to degrade internally over time, which causes them to act like check valves rather than hoses. I have a set of brand new stainless steel lines that I'll be putting on to see if that is the case within the next week or so, once I finish fixing some other things.
You can confirm what wheels are affected by putting the car in the air, unbolting the master cylinder from the brake booster, and then trying to spin the wheels. On mine, my driver's front would not spin freely despite the master cylinder being removed (I was testing to see if the brake booster pushrod was out of alignment; it wasn't).
If it's not the lines, then it's time for a caliper rebuild.
Best of luck!
You can confirm what wheels are affected by putting the car in the air, unbolting the master cylinder from the brake booster, and then trying to spin the wheels. On mine, my driver's front would not spin freely despite the master cylinder being removed (I was testing to see if the brake booster pushrod was out of alignment; it wasn't).
If it's not the lines, then it's time for a caliper rebuild.
Best of luck!
Thread Starter
Instructor
Joined: Jul 2018
Posts: 216
Likes: 36
From: Frisco, TX
Sorry for your problem, but good to hear I'm not the only one. I would think that if it was a booster pushrod out of alignment, it would happen all the time. I was planning on driving it around the neighborhood until it happened so I could jack the front end as you said. the back is a bit more difficult with the Dana 44. I think it would be hard to tell if the back brakes were binding. If you are able, try to take the temp of your rotors after driving. Please post back if the new lines fix the problem.
Thanks for the response,
Nick
Thanks for the response,
Nick
Thread Starter
Instructor
Joined: Jul 2018
Posts: 216
Likes: 36
From: Frisco, TX
Just took the car out to run it and get it up to temp. Felt the brakes binding. Pulled back into the garage, jacked up the right front and I could NOT turn the wheel by hand. Rotor was at 260 degrees. Left it jacked while it cools. Will see when I can turn the wheel by hand.
30 minutes later, the rotor is down to 160 and the wheel spins freely. Interesting.
30 minutes later, the rotor is down to 160 and the wheel spins freely. Interesting.
Last edited by Nick Bernier; Jun 15, 2020 at 03:40 PM. Reason: Add detail
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
Just took the car out to run it and get it up to temp. Felt the brakes binding. Pulled back into the garage, jacked up the right front and I could NOT turn the wheel by hand. Rotor was at 260 degrees. Left it jacked while it cools. Will see when I can turn the wheel by hand.
30 minutes later, the rotor is down to 160 and the wheel spins freely. Interesting.
30 minutes later, the rotor is down to 160 and the wheel spins freely. Interesting.
Instructor
Joined: Mar 2019
Posts: 142
Likes: 36
From: Southern New Hampshire
If you are getting a shudder at speed or while braking and your calipers have been sticking for what ever reason, you may have one or both warped rotors. Heat can generate the warp. It may be work replacing the pads and rotors when you do the lines. It may not let you isolate the issue by doing it all at once but if the issue disappears you have it solved and do not have to tear into it twice. If not, you have fewer systems/things to focus on.
Just my two cents. (may not even be worth that much!)
Just my two cents. (may not even be worth that much!)
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
That's a good test: When you have the brakes hot, and the brakes are dragging, loosen the bolts of the m/c. If this relieves the drag on the brake, the pushrod is too long If it doesn't relieve the drag, your problem is elsewhere.
With a properly adjusted pushrod, if you remove the caps of your m/c, you should see a small spurt or a disturbance in the surface of the brake fluid when you first move the brake pedal.
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Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
Sounds to me like the front rubber hoses. As stated above they tend to act like a check valve when they get degraded. Then with the heat the rotors/pads expand.
i always try to explain the one-way flow like a pinched drinking straw. You can blow fluid through it...but can’t suck anything back through. So your fluid is most likely getting pushed to the calipers but now flowing back out.
i always try to explain the one-way flow like a pinched drinking straw. You can blow fluid through it...but can’t suck anything back through. So your fluid is most likely getting pushed to the calipers but now flowing back out.
Instructor
Joined: May 2020
Posts: 159
Likes: 17
From: Northeast, Ohio
Only my opinion based on experience with other vehicles, without over diagnosing I'd say the caliper needs rebuilding.. heat is causing it to "stick".. but what do I know, I'm a newbie here.. another just my 2 cents post by me!
Pro
Joined: Sep 2018
Posts: 671
Likes: 171
From: Birmingham, Alabama
My 95 is doing the same thing. Temps on the front right, which is dragging the most, are 20 degrees warmer than the front left. I've found a couple articles and they seem to be divided between the front brake hoses and an issue with the ABS module. Keep us posted; seems like several of us are dealing with it right now.
Last edited by 95LT1ZF; Jun 16, 2020 at 05:39 PM.
Thread Starter
Instructor
Joined: Jul 2018
Posts: 216
Likes: 36
From: Frisco, TX
Since the ABS is mounted way in the rear, I wouldn't expect it to be as affected by engine heat. I'm thinking (and hoping) it's the hoses. I want to flush the brake fluid anyway, so this would be the perfect time to swap them out.
Nick
Nick
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
It's not engine heat that's the problem. You fluid gets hot from using your brakes, and then especially from dragging brakes!
What are the chances that both front brake hoses would fail at the same time?
You can test whether the calibers are sticking by getting the brakes hot, so they're dragging, then open the bleeder screw. Do the brakes release?
What are the chances that both front brake hoses would fail at the same time?
You can test whether the calibers are sticking by getting the brakes hot, so they're dragging, then open the bleeder screw. Do the brakes release?
Racer
Joined: May 2020
Posts: 345
Likes: 68
From: New Jersey
It's not engine heat that's the problem. You fluid gets hot from using your brakes, and then especially from dragging brakes!
What are the chances that both front brake hoses would fail at the same time?
You can test whether the calibers are sticking by getting the brakes hot, so they're dragging, then open the bleeder screw. Do the brakes release?
What are the chances that both front brake hoses would fail at the same time?
You can test whether the calibers are sticking by getting the brakes hot, so they're dragging, then open the bleeder screw. Do the brakes release?
So as I stayed before...I’d put money on the hoses. Hell I’ll pay for it if it doesn’t solve the issue. All he’s got to do is PM me and I’ll reimburse him. Anyone else care to put their money where their fingers are?
Thread Starter
Instructor
Joined: Jul 2018
Posts: 216
Likes: 36
From: Frisco, TX
Thanks for offering to pay for the hoses if wrong, but not my first rodeo. I only jacked the passenger side to try to spin the wheel. Never jacked the driver's side, but both rotors were at about the same high temp (assumed from dragging). Seems that opening the bleeder would release the pressure whether it was a sticking caliper or a plugged hose, no?
Still thinking it's the hoses. It's been doing this since I bought it almost a year ago.
Thanks,
Nick
Still thinking it's the hoses. It's been doing this since I bought it almost a year ago.
Thanks,
Nick
Safety Car
Joined: Sep 2004
Posts: 3,953
Likes: 550
From: Mission Viejo CA
I don't know anything about ABS systems, so I'm not going to comment on that. I'm only trying to help you narrow down your problem, one step at a time.