I have a brake fluid leak between the master cylinder and the reservoir. I am assuming it is the gasket but would like to know if there is any other thing that needs to be done and if there are any tips on changing the gasket. It seems pretty straightforward but I have never done this before.

 

There are two rubber grommets that seal the reservoir to the master cylinder itself, those are what cause the leak as you have already figured out. You can only buy those seals as part of a larger kit for around $90. Replacing them is pretty straightforward, you do need to press down fairly hard on the reservoir to seat it against the new seals while you slide the metal retaining pin in place. Just did mine yesterday.


You could buy a full rebuild kit and remove the master cylinder and completely replace all the seals inside while you're at it, I didn't bother. If you want to make less of a mess, remove as much of the old fluid as possible from the reservoir before you remove it. Keep the fluid off the paint naturally, and wash down the inner fender area when you're done.

 

Do those rubber grommets tend to fail often. Those were replace right before I purchased the truck 7 years ago with 51,000 miles.