• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Silicone Brake Fluid

C

Cockroach

New Member
Local time
8:34 AM
Joined
Jul 14, 2025
Messages
1
Reaction score
5
Location
49685
As the original owner of a 68 Roadrunner, and reading many posts over the years......some very accurate, some not so much, I decided to join and share my 57 years of experience of driving and maintaining my 68 Roadrunner. I'm going to start with the use of Silicone Brake Fluid, as there seems to be some confusion as to Silicone Brake Fluid's effectiveness. 45 years ago, I converted my 68 Roadrunner to Silicone Brake Fluid; Since doing this, I have not had a single issue: no hydraulic issues, no soft pedal issues, no ruined paint issues from spillage, and the fact that the US Military utilizes Silicone Brake Fluid, quite frankly has me puzzled, as to why more old Mopar Muscle Car Owners, are not embracing Silicone Brake Fluid, as I have for the last, almost half Century!? 5 years ago, I decided to flush my 40 year old Silicone Brake Fluid, and the old fluid flushed out clean, and un-contaminated..... the only change was the purple dye, that is added to Dot 5 Silicone Brake Fluid had faded, and the Silicone Brake Fluid was about the same color as traditional brake fluid. Which is normal, based on other blogs on-line. So what are YOU waiting for; Flush out your old traditional brake fluid (COMPLETELY), put Silicone Brake Fluid in, and never have to touch your Brake Hydraulics for the next 50 years!!
 
Welcome to FBBO from Georgia.

Feel free to post pictures of your car, yourself, etc.
 
Welcome to FBBO. I converted my car to Dot 5 brake fluid and I plan on doing the same for all eventually.
 
Last edited:
Welcome Cucaracha!

I've been using dot 5 for 6 years now. Fluid in the master cylinder is still as clean as it came out of the bottle and still purple.
 
Cockroach said:
As the original owner of a 68 Roadrunner, and reading many posts over the years......some very accurate, some not so much, I decided to join and share my 57 years of experience of driving and maintaining my 68 Roadrunner. I'm going to start with the use of Silicone Brake Fluid, as there seems to be some confusion as to Silicone Brake Fluid's effectiveness. 45 years ago, I converted my 68 Roadrunner to Silicone Brake Fluid; Since doing this, I have not had a single issue: no hydraulic issues, no soft pedal issues, no ruined paint issues from spillage, and the fact that the US Military utilizes Silicone Brake Fluid, quite frankly has me puzzled, as to why more old Mopar Muscle Car Owners, are not embracing Silicone Brake Fluid, as I have for the last, almost half Century!? 5 years ago, I decided to flush my 40 year old Silicone Brake Fluid, and the old fluid flushed out clean, and un-contaminated..... the only change was the purple dye, that is added to Dot 5 Silicone Brake Fluid had faded, and the Silicone Brake Fluid was about the same color as traditional brake fluid. Which is normal, based on other blogs on-line. So what are YOU waiting for; Flush out your old traditional brake fluid (COMPLETELY), put Silicone Brake Fluid in, and never have to touch your Brake Hydraulics for the next 50 years!!
Click to expand...
I used all Dot5 also.. lost it's purple fast but it's nice to not destroy paint.. and i got tons of it in my engine bay (pressure bleeder leaked) and just wipe it up :)

BTW... i thought that if you put dot5 in a system that had normal fluid it will destroy any seals/rubber, even if you drain the system it still has enough to cause a reaction?
 
icetech said:
I used all Dot5 also.. lost it's purple fast but it's nice to not destroy paint.. and i got tons of it in my engine bay (pressure bleeder leaked) and just wipe it up :)

BTW... i thought that if you put dot5 in a system that had normal fluid it will destroy any seals/rubber, even if you drain the system it still has enough to cause a reaction?
Click to expand...
That is correct, they do not mix. Dot 5 also does not work with abs.
I just replaced everything on my 66 Coronet, stainless lines, wheel cylinders, converted to disc up front, so new calipers and also converted to power disc, so new master cylinder. Other than being very expensive, it is all positives for me as well so far.
 
Bit of extra work flushing & bleeding but 2 years now without any issue
 
Switching to DOT 5 makes sense if you are trying to protect your paint from spills.
You sure pay for it though....the stuff I've used is right near $40 a quart!
 
No thanks! All normal manufacturers run dot 3/4. For multiple reasons.
 
Kern Dog said:
Switching to DOT 5 makes sense if you are trying to protect your paint from spills.
You sure pay for it though....the stuff I've used is right near $40 a quart!
Click to expand...
Yeah.. the stuff is stupid expensive and i have gone through a lot of it trying to get my brakes working properly... hate wasting money and i'm really good at it :)
 
I’ve had DOT5 in one old car for 30+ years and recently switched my 66 Satellite over to it. No problems with it. I believe some of the hesitation to switch over to it has been the number of brake component manufacturers who started slapping stickers on their products that use of DOT5 will void the warranty. Personally I think it’s a bunch of BS based on some perceived ***-covering misconception - but it confuses people. For instance Triton doesn’t recommend DOT5. Raybestos does not universally recommend it either. I think a lot of it stems from fear people will switch to DOT5 without properly flushing the system or try to use it in newer anti-lock braking systems that aren’t designed for it.
 
Why is the topic of why EXACTLY silicone BF's are not allowed with ABS would I suspect be rather telling.
Meaning there is a reason, and it appears to be a third rail in discussions.
 
j-c-c-62 said:
Why is the topic of why EXACTLY silicone BF's are not allowed with ABS would I suspect be rather telling.
Meaning there is a reason, and it appears to be a third rail in discussions.
Click to expand...
took 5 seconds to find...

DOT 5 brake fluid is not used with ABS (Anti-lock Braking System) equipped vehicles primarily because it's silicone-based and can foam excessively when agitated by the ABS system's rapid on/off cycling. This foaming creates air-like bubbles within the brake lines, leading to a spongy brake pedal and reduced braking performance, potentially causing a complete brake failure
 
icetech said:
took 5 seconds to find...

DOT 5 brake fluid is not used with ABS (Anti-lock Braking System) equipped vehicles primarily because it's silicone-based and can foam excessively when agitated by the ABS system's rapid on/off cycling. This foaming creates air-like bubbles within the brake lines, leading to a spongy brake pedal and reduced braking performance, potentially causing a complete brake failure
Click to expand...
But my real point was, that long known observation seems to be mostly ignored and avoided by silicone advocates.

"Why is the topic of why EXACTLY silicone BF's are not allowed with ABS would I suspect be rather telling.
 
Welcome to FBBO from NorCal Sierras

good to have a guy with 57 years experience on the board/forum :luvplace:
 
Welcome from PA. It's great to have someone aboard who was there back in the day, and still with us. It's a shrinking pool, congratulations on going the distance!
 
Welcome. Need a pic for your avatar ? >
1752608605126.png
 
You must log in or register to reply here.

Similar threads

Migsbig
FOR SALE 1996 Dodge Viper GTS, CA
Replies
3
Views
2K
Migsbig
Migsbig
racingjim
4 Wheel Disc Conversion
Replies
2
Views
344
ckessel
ckessel
M
  • Locked
SOLD Brake Master Cylinder, Dist Valve + 2 lines
Replies
2
Views
759
mnewell337@gmai
M
F
Brake fluid seep from master cylinder
Replies
3
Views
600
tonysrt
T
M
Brake Issue Using Dot 5
2
Replies
36
Views
2K
mrhemi
mrhemi
Auto Transport Service
Back
Top