I've never seen any need for it in the automotive world. Especially in your case, because you will be putting it in your "old Darts brake system". Why you ask? Because under no circumstances can dot 5 mix with ANY other type brake fluid. Not even in the least amount. That is unless you want to replace every bit of rubber in the system. If the system has had dot 3, stick with dot 3 or you're askin for trouble. Mixing the fluids will make every rubber part swell up and soften up and be worthless.
