Ford Mustang Forums banner

1 - 20 of 26 Posts

·
Registered
Joined
·
86 Posts
Discussion Starter #1
Car Info: 89 foxbody, 3170lbs with driver, 324hp
Brakes: Cobra 4wdisk conversion, stop tech "street pad", Power slot rotors. No brake ducting. No dust shield. Motor craft 500degree fluid, maybe 2 years old? I cant remember if we swapped it out when we changed the engine earlier this ear.

Anyway

I drove my car to the track the other day, and after about 8 laps on the noon time session, They black flagged everyone for some reason, and we sat for about 5-8 min in the hot pits. I had no brake fade during the session, everything seemed fine (I was chasing a 96 stang' down and was driving the car, and using all of the brakes.)

After sitting for 8 min or so they restarted the session and I pulled up to the started, and had almost no brakes. After I determined that I wasn't loosing fluid anywhere, I babied it back to the pits, and started scratching my head.

It was bloody hot, I was having other non-related mechanical issues, and the day was just not going well. So I let the car cool for about an hour and called it a day. Well the brakes came back, and I was able to drive it home with no problems.

So what kind of fade was this? I have heard of pad fade and rotor fade and fluid fade. I have had older fluid cause fade, but that occured During a braking zone, not 10 min after

Maybe all the heat from the rotors had time to transfer to the pads and fluid during that period when we were stopped?

I'm going to change the fluid completely out anyway, but is it time for a "Track pad"?

Thanks!
 

·
Registered
Joined
·
303 Posts
Brakes were hot and while you sat the pads got heat soaked and your fluid probably got cooked a bit as well.

There are a lot of issues.

First, you did a track event with 2 year old street fluid. You should always, at a minimum, bleed 5-6 pumps from each caliper. This clears out the fluid that was in the caliper at the last event and gets some better fluid in there. But, if you had not done a bleed in 2 years you needed a good thorough bleeding.

Second, "street pads".

Not sure of your experience level, but since you were on 1-2 year old fluid I am guessing your a novice. If you are reasonably experienced you need coolant ducts.
 

·
Registered
Joined
·
86 Posts
Discussion Starter #4
I appreciate the speculation on my experience. I suppose I'll always be a novice compared to some of the fastest drivers on the internet.

So pads and fluid. Sure. The track was Autoclub infield, its kind of small. Lots of braking and two minor straights, the past half a dozen times I've been here have been with the roval. The reason why this is worth discussing is because on the infield track there is a lot more braking and less time for the brakes to cool. So why didn't the fade on the track? Pads and fluid will tell I suppose.
 

·
Registered
Joined
·
564 Posts
Spongy pedal = fluid fade. Normal pedal, no stopping power = pad fade. Which was it?

Either way, tracking on 2 year old fluid isn't a good idea. Also, when you're sitting like that, make sure you don't hold the brakes. That'll cook pad material onto the rotors.
 

·
Registered
Joined
·
662 Posts
IMO, you boiled the fluid...you should, at a minimum, do a complete flush and fill of fresh fluid (preferably something with a higher boiling point than motorcraft fluid) once a year.
 

·
Registered
Joined
·
326 Posts
Spongy pedal = fluid fade. Normal pedal, no stopping power = pad fade.
If the brakes were fine in the next session after a sufficient cool-down, the pads were overheated.

Boiling the fluid that creates compressible bubbles and a spongy pedal doesn't go away until you flush the fluid.
 

·
Registered
Joined
·
1,382 Posts
If the brakes were fine in the next session after a sufficient cool-down, the pads were overheated.

Boiling the fluid that creates compressible bubbles and a spongy pedal doesn't go away until you flush the fluid.
Fluid will come back but will boil more quickly the next time and even quicker the next.
 

·
Registered
Joined
·
4,669 Posts
Does anyone recommend another brake fluid for street and track use? I know there are lots for track use with great dry ratings, but lower wet ratings than Motorcraft so not as "streetable" as the Motorcraft stuff since it has to be replaced more frequently. What do people here use?
 

·
Registered
Joined
·
200 Posts
I put Wilwood EXP in my dail driver SRT8 4+ years ago when I started tracking that car and bled it every other event. I went to a dedicated track/race car nearly 3 years ago and still have that EXP in the SRT8 to this day.

Brakes are the single most important thing on a track car. Maintain them and save money somewhere else......the advice so far is sound.
 

·
Super Moderator
Joined
·
27,651 Posts
I run MOTUL 600 because it has the highest wet boiling point for the money. Dry boiling point is meaningless unless you're flushing the fluid all the time. Real world, wet boiling point is more important.
 

·
Registered
Joined
·
4,669 Posts
^^^ that's what I was thinking (wet vs dry performance) so that's why I used the Motorcraft, but you are saying the Motul 600 has a higher wet rating as well?
 

·
Super Moderator
Joined
·
27,651 Posts
Here's a handy chart that's sortable by column (boiling points, price). If you want higher wet boiling point than Motul 600, you have to cough up more money. It provides the 4th highest wet boiling point at the 28th highest cost per oz. I have not vetted this, I'm trusting it's good, but it jives with everything I've seen going back several years.

https://www.lelandwest.com/brake-fluid-comparison-chart.cfm?startRow=1&SF=4&ST=2
 

·
Registered
Joined
·
1,382 Posts
Motul 600 here! I flush it once a year and nothing between weekends.
 

·
Registered
Joined
·
4,669 Posts
The other one I know of is (and I can't remember the name but it is in German) a blue or yellow fluid which you alternate so you know when you completely flush it out.

Edit : It's called ATE and its def German, maybe made by Contiental? Anyway the Motul looks like an excellent buy based on the specs and the price, considering to get better performance you have to spend 4-5 times the money. Oh and it's illegal accordin to the US DOT I guess? Braking News: ATE Super Blue Deemed Illegal for US DistributionÂ#|Â#Hooniverse

Either way it doesn't matter since the specs are worse than the Motul you guys have recommended for basically the same price. When changing from Motorcraft, which I think is DOT 3, to Motul which is DOT 4, does anything special need to happen other than completely flushing out the old Motorcraft stuff?

Sorry for the thread derailment, but if OP is using Motorcraft and getting brake fade after awhile, I hope this info might help him too. On a related note, anyone need a sealed bottle of Motorcraft brake fluid? :D
 

·
Super Moderator
Joined
·
27,651 Posts
Motorcraft should be DOT 4 but in any case, it's mixable/compatible with most others except DOT 5. BTW ATE made different colors so the user could tell when the system had been flushed properly. The idea was to alternate between Blue and Type 200 (same properties, different color) with each flush. The ONLY thing that makes Blue illegal is apparently there's verbage in the DOT language that says the fluid has to be clear or amber or some ####.
 

·
Registered
Joined
·
4,669 Posts
Yea I knew that about the ATE but didn't realize the only reason for the DOT statement was because of the blue color - hell its great they sell them in both colors for exactly that reason of ensuring a complete flush and having something obvious for the non-gear head customer. Moot anyway I guess if the Motul RBF 600 is better for less money and easier to find.

On a related note, where does everyone buy their Motul from for the cheapest? I'm well overdue for a flush and have noticed the fade and need to do this soon. Pads have lots of life and are wearing evenly and rotors look ok so just gonna do the fluid.

Sorry for the thread hijack OP :(
 

·
Super Moderator
Joined
·
27,651 Posts
I get mine at Summit or racerpartswholesale. I think I've even gotten it from Amazon.
 
1 - 20 of 26 Posts
Top