Sorry if this is a repost but I haven't seen anything on this recently and the search is down.

First question: are there any notable differences between stoptech SS lines and the goodridge lines? They have similar prices and both seem to have great reputations. Is there any reason to get one over the other?

Second question: what's the big difference in motul 5.1 and 600? From what I've been able to gather, the 5.1 seems to be thinner and designed for braking systems with ABS. The 600 has a high wet boiling point and is good in the rain. It also seems to be more expensive. Is there any reason to get one over the other here?

TIA

 

They are both so close, it is doubtful anyone will could notice a difference in feel nad/or performance. I have had Stoptech brakes in the past and I really like Stoptech as a company, but I bought the Goodridge lines... only reason was the Goodridge were available and Stoptechs were not.


5.1 and RBF600 will both work in ABS systems. Both are high temp fluids... meaning they will resist high temperatures and will not boil in your calipers.... very good if you do a lot of track events. If you are only street driving, RBF600 is WAYYYY overkill. Also, you have to replace RBF600 about every 10k miles or 10-12 months. For the street, get the 5.1 and save a few bucks. For track events, get the 600.

One brake fluid is not better in the rain than another. What the wet boiling point means is the fluid will boil at that temperature once it has absorbed a certain amount of moisture from the air. All brake fluids are hygroscopic... meaning they absorb moisture when exposed to the atmosphere. As the fluid absorbs moisture, the boiling point will come lower. Eventually the fluid will absorb so much moisture that it will no longer work.

Hope that helps,

PeteH

 

Why do you have to change the motul brake fluid every 10k miles. Thats a pain to have to do that. What happens if you don't?

 

The Motul is very hygroscopic.

 

yep... JawKnee hit it on the head. Motul 600 will absorb a lot of moisture from the atmosphere. You don't have to change it... but if you do track events it won't work any better than OEM fluid once it's saturated. Many HPDE organizations will test your brake fluid to make sure it's new enough and if you don't pass, you don't play.

All brake fluids should be changed every two years. All brake fluids absorb moisture and break down over time. Maintaining your brake fluid is very important. Even if you never do track events, the fluid could fail when you need it in an emergency situation on the street.

Cheers,

PeteH

 

I've always used ATE SuperBlue / Typ200, but will be switching to Neosynthetic once I use up the ATE. Here's a list somebody else compiled for comparison...

DRY:401F -- WET:284F --- DOT3 MINIMUM (GLYCOL BASE)
DRY:446F -- WET:311F --- DOT4 MINIMUM (GLYCOL BASE)
DRY:500F -- WET:356F --- DOT5 MINIMUM (SILICONE BASE)
DRY:500F -- WET:356F --- DOT5.1 MINIMUM (GLYCOL BASE)
DRY:509F -- WET:365F --- MOTUL 5.1
DRY:527F -- WET:302F --- AP RACING 551 ($12.95/0.5L OR 16.9 OZ)
DRY:527F -- WET:347F --- VALVOLINE SYNPOWER DOT3 & DOT4
DRY:536F -- WET:392F --- ATE SUPERBLUE/TYP200 ($9.95/1L)
DRY:550F -- WET:284F --- FORD HEAVY DUTY DOT 3 ($4/12 OZ)
DRY:570F -- WET:284F --- WILWOOD 570 ($5.65/12 OZ)
DRY:570F -- WET:284F --- PERFORMANCE Friction Z rated ($6.27/16 OZ)
DRY:590F -- WET:410F --- AP RACING 600 ($16.95/0.5L OR 16.9 OZ)
DRY:590F -- WET:518F --- CASTROL SRF ($69.00/1L 0R 33.8 OZ)
DRY:593F -- WET:420F --- MOTUL RBF600 ($12.95/0.5L OR 16.9 OZ)
DRY:601F -- WET:399F --- BREMBO LCF 600 PLUS ($26.75/0.5L OR 16.9 OZ)
DRY:610F -- WET:421F --- NEO SYNTHETICS SUPER DOT 610 ($11.95/12 OZ)
DRY:610F -- WET:421F --- PROSPEED GS610 ($39.95/16 OZ)
DRY:626F -- WET:417F --- WILWOOD EXP 600 ($16.95/0.5L 16.9 OZ)