Some things are certain: death, taxes, and, if you own your Triumph long enough, your master brake/clutch cylinder is going to leak. If you are using DOT3, DOT4 or DOT5.1 brake fluid, the leaking fluid will eat any paint that it touches. You also risk dripping these fluids onto your car’s paint finish when topping off the brake and clutch cylinders.

Six or seven years ago I flushed the brake and clutch system in my TR250 with denatured alcohol and replaced the old DOT4 paint-eating brake fluid with DOT5 brake fluid, also known as "silicone" brake fluid. Silicone will not harm your car’s paint finish. I have never had a problem with this conversion. I was going to convert my TR3 to silicone but procrastinated. Low and behold the master cylinder is leaking on the TR3 and has ruined an area of paint in my nice looking engine compartment. The fluid also leaked down into the driver side footwell and ate the paint on the brake and clutch pedal assembly, as well as the bulkhead paint on the inside of the car directly under the master cylinder. I am now repainting the area around the brake cylinder, the pedal assembly and all of the other areas that came into contact with the DOT4 fluid. An aggravation and expense that I could have avoided if I wouldn’t have procrastinated.

There are plenty of discussions of whether to use DOT3, DOT4, DOT5, or the newer DOT5.1. Do your own research and draw your own conclusions. My experience indicates that DOT5 is probably the best choice for the weekend driver and showcar. I will convert my TR8 to silicone next … when I get the time!

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