[Billabongi]

I tried searching and couldn't find the answer. I have a 17 SS that is mostly daily driven but I do take it up to the Carolina's/Tennessee Mountains. Last time I did this (deals gap) I cooked the brakes pretty good so just looking to slightly improve things to where I still have a DD that can handle the occasional spirited driving session. If the car ever sees the track it'll be a 1 off scenario so not looking to go full blown track duty but something that can hold the line between them both.



For the most part anything I see about DOT4 is you need to replace it every year or so which I would prefer not to do. Wasn't sure if that was just for that specific fluid or for all DOT 4.

[TJay74]

You can run DOT4 but you will need to change it every 1-2 years, it absorbs moisture faster than DOT3.

[Alpha1BC]

Originally Posted by TJay74

You can run DOT4 but you will need to change it every 1-2 years, it absorbs moisture faster than DOT3.

That's not necessarily the case. DOT 3 is actually a little more prone to absorbing water than DOT 4, it's just that the boiling point of DOT 3 doesn't degrade as much as DOT 4 does for the same amount of water content. DOT 4 is typically changed more frequently because people use it for track use where you want to be as close to the dry boiling point as possible so you typically don't go for more than a year or so without putting fresh fluid in.

As for what OP could do with mountain runs, if you're heating the brakes similarly to how they'd be heated on a track, you'll want to treat it like you're using it on the track. There's a video I saw floating around the forums where someone took their car to the track on DOT 3, boiled fluid, and slammed into a wall as a result. Annual DOT 4 fluid changes will help ensure you don't boil brakes or have issues, which is what I'd personally be doing if the alternative meant relying on a guard rail to keep the car from taking the quick route down the mountain.

If you want to be more scientific about it, temp strips/paint can be used to see what temps you're actually reaching. From there you can judge if there's a need for DOT 4 or not.

[Billabongi]

Thanks for the help was hoping there was a dot 4 fluid out there that could last two years (in my case about 14-16k miles in that time frame)

Will have to think about doing annual brake fluid changes.

[TRZ06]

I run Castrol SRF Dot 4 in my car and it's a daily that does not see the track, just mountain roads and back roads.

I plan to do a flush annually.

[trohde78]

I settled on Motul DOT 5.1 for my last 3 cars that see some light track duty (stock pads, tires, etc.) Not really sure what the water absorption rate is for that stuff, but it seems to be in a nice spot as far as boiling points somewhere between DOT 3 and the "racing" DOT 4 options. It's also cheaper than the mentioned DOT 4 fluids. Never had any issues on the street or track.

[ZZP_Tyler]

I've run Pentosin Dot 4 in all of my cars the last few years, my daily as well as the car(s) that see the track. It has yet to let me down and can be found at Autozone for a solid price. Just make sure not to get the DOT 4 LV (low viscosity) version, they usually put them in the same slot on the shelf.

[mjk3888]

Castrol SRF! i daily my SS 1LE and run 3-5 track events a year. I have about 20k miles on SRF fluid and I have only flushed once. Very happy!

[Billabongi]

Thanks all appreciate the assistance. Really curious about SRF but boy is it expensive!

[BlueinTN]

I run the Dot 4 type fluids for about 25 years now....I think they do draw in moisture more then your box stock DOT 3. Fluid color usually tells but you can get moisture test strips and test your self. I found a NOTICEABLE difference when changing the fluid so it was good enough for me.



usually yearly I just suck out the master cylinder with a turkey baster as far as I dare and replace with fresh fluid. On some of my rides with steering racks i do the same thing since they seem to over heat the fluid as well.


This isnt a COMPLETE flush but it gets the job done minimal mess,cost,stress.


Last few years the Motul 5.1 seems pretty good. My favorites fluids was the Castrol GTLMA but it went away a few years ago and I used up my old stock about 2 years ago.

[Billabongi]

Originally Posted by BlueinTN

I run the Dot 4 type fluids for about 25 years now....I think they do draw in moisture more then your box stock DOT 3. Fluid color usually tells but you can get moisture test strips and test your self. I found a NOTICEABLE difference when changing the fluid so it was good enough for me.



usually yearly I just suck out the master cylinder with a turkey baster as far as I dare and replace with fresh fluid. On some of my rides with steering racks i do the same thing since they seem to over heat the fluid as well.


This isnt a COMPLETE flush but it gets the job done minimal mess,cost,stress.


Last few years the Motul 5.1 seems pretty good. My favorites fluids was the Castrol GTLMA but it went away a few years ago and I used up my old stock about 2 years ago.

Ive heard several people mention Motul 5.1 now and after looking at it that might be my first move. Seems to be great for street and light track duty. If I cook this one I’ll go up to 600 or SRF

Thanks for all the help everyone it helped me and I’m sure it’ll help others with the same predicament.