Need some help, I feel like this is repeating a question but I can't find the exact answer to it. The single hole in the plate that has the 6 colts coming out of it. I have oil coming out of that hole... I just did the seals 5 months ago and my friend insist that there should be oil behind the gasket on the back of this plate. I am assuming that since oil came out of this hole in the plate that this means a seal is blown? please look at the picture and let me know what you think. I think I just caught the leak very early cause the brakes aren't greasey at all. My friend-mechanic said fill the hole with silicone. but what is the purpose of this hole? to let you know if there is a blown gasket? wouldn't water get in the hole if you went off roading? So once again small hole on the plate whats it for? and whats the gasket for behind it? if there is oil in there is it okay?

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