The SMWBO's new ride, 2012 Suburban, is up for for some super preventative maintenance on the brake fluid. All in all though, the brakes are down right dangerous, thanks GM. So, I'm going to change out the pads while I'm there too. It just doesn't stop all that well, going back to the Hawk LTS series like I put on her previous DD. It really doesn't go great either. Oh well.
What say ye ole GRM?
Whatever DOT4 is on sale at the local parts shop should be more than adequate.
What slick said.
Castrol GT-lma DOT4 is my favorite, and its not that much more expensive than generic brand brake fluid, and way cheaper than "racing" brake fluids, and in my (admittedly limited) experience, works just as well.
I always use the Valvoline Dot 3/4 Synthetic brake fluid. Always works just fine for me for anything outside of pure track applications.
Castrol SRF is the best, but any DOT4 will be more than good enough for street use.
SlickDizzy wrote: Whatever DOT4 is on sale at the local parts shop should be more than adequate.
I always get the best petal (and lever) feel with the cheap name brand stuff. How it would hold up in auto racing duty I don't know, it's fine on in my bike for 8 lap sprints, 25 minute endurance and who know how much track time on a test and tune or track day.
Steve
If the intent is to find a fluid that will last as long as possible, I'd look for one with a wet boiling point closest to the dry boiling point. Castrol LMA (Low Moisture Absorption/Activity/Avidity) is built for this.
Keith Tanner wrote: If the intent is to find a fluid that will last as long as possible, I'd look for one with a wet boiling point closest to the dry boiling point. Castrol LMA (Low Moisture Absorption/Activity/Avidity) is built for this.
And is getting hard to find. I have to mail order it now.
Thanks. Just looking for some better pedal then the near current slip and slide braking mode it has right now.... Plus in the future will be some towing and up and down the mountains will cook the brakes on top of the people who refuse to actually drive on the road.
New fluid is always better than old.
Aside from that, if you're having issues with brake fluid, you should probably re-evaluate either your driving tactics or your choice of vehicle. If wet boiling point is a concern, then you should have changed the fluid a long time ago anyway.
I'm assuming this beast has some sort of towing mode that uses engine braking instead of the brake pedal to control descent speed.
BTW, the wet boiling point is for 3.7% water absorption.
None of the brake fluids are compressible, so a high quality fluid won't solve the pedal feel unless there is something dreadfully wrong with the fluid in there; wet/boiling, has air.
For that matter, you could theoretically put kerosene, corn oil, or whiskey in it and have the same pedal feel.
A high quality fluid will last longer in terms of water absorption and boiling point, but fluids aren't compressible so they don't have anything to do with the performance or feel of the braking system.
And don't fall for "synthetic" brake fluid. Its glycol. Its all synthetic. There is no such thing as a glycol plant.
On a sidenote... I didn't see anyone recommend Ate brake fluid. It used to be the creme de la creme. Still good stuff? Or has something else surpassed it?
Gear oil works as a substitute for brake fluid but it definitely changes the feel. Especially when it's cold outside.
In reply to curtis73:
ATE is great stuff but it's hard to find locally and I wouldn't say it's worth ordering for a DD Suburban. I use it in a lot of stuff because I still have unopened Super Blue kicking around, but I'd think plain old parts store DOT4 would do just fine here.
SlickDizzy wrote: In reply to curtis73: ATE is great stuff but it's hard to find locally and I wouldn't say it's worth ordering for a DD Suburban. I use it in a lot of stuff because I still have unopened Super Blue kicking around, but I'd think plain old parts store DOT4 would do just fine here.
Agreed. I use plain Prestone DOT 3/4
Keith Tanner wrote: If the intent is to find a fluid that will last as long as possible, I'd look for one with a wet boiling point closest to the dry boiling point. Castrol LMA (Low Moisture Absorption/Activity/Avidity) is built for this.
That stuff also meets at least DOT4 spec...I have some bottles of it so it at least used to be available by me, I should probably put that in my Samurai next time I change the change the brake fluid instead of the cheapo DOT4. It's not like those brakes get used too heavily.
curtis73 wrote: None of the brake fluids are compressible, so a high quality fluid won't solve the pedal feel unless there is something dreadfully wrong with the fluid in there; wet/boiling, has air. For that matter, you could theoretically put kerosene, corn oil, or whiskey in it and have the same pedal feel. A high quality fluid will last longer in terms of water absorption and boiling point, but fluids aren't compressible so they don't have anything to do with the performance or feel of the braking system. And don't fall for "synthetic" brake fluid. Its glycol. Its all synthetic. There is no such thing as a glycol plant. On a sidenote... I didn't see anyone recommend Ate brake fluid. It used to be the creme de la creme. Still good stuff? Or has something else surpassed it?
I still use it in my TT/autoX car … both the Amber and the Blue
In reply to Knurled:
No, it's got 60k on it, it's big and heavy, and is due for a change. Most of the pedal fell is the junk oe pads but pushing harder on the pedal sure doesn't bring any confidence in actually getting stopped.
As far as "pedal feel" is concerned you could put pure water in there and get a great pedal as water in not compressable. But as to it's boiling point well we all know what that is.
the "pushing harder doesn't improve things" usually means pads .. as for old used fluid, if it's been in there that long, it SHOULD be changed (as all the others have said) … if you can pump the pedal up any, that means that there's air in there … comes from old over heated and water satiated fluid
if you weren't towing I'd suggest that DOT 3 would be fine … odds are that's what was OEM … but most DOT 4 fluids do have a higher boiling point … and the number to look for is wet boiling point … much more important than dry boiling point … why ? you ask .. because the brake fluid is considered dry ONLY when brand new … it starts absorbing water immediately … hence the importance of wet boiling point
What in particular is wrong with the "feel" of the pedal? Sometimes there is an adjustable rod between the master and the pedal assembly, you may need to adjust it here... if you need an adjustment.......
I'm also with the DOT 4 fluid that's available camp.
wbjones wrote: if you can pump the pedal up any, that means that there's air in there
Or the slide pins are sticking/pads are rusted to the hangers, so the only way the outboard (or both) pads make contact is through things flexing. You usually can pump the brakes up if you're quick enough just like air in the system.
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