I brought my truck in the morning and it was out later that afternoon. John the owner really saved me big time. I brought my truck to 3 other mechanics who ended, either wanting way too much money to fix it or didn't know how to fix it. It's always good to know that you have a trustworthy mechanic. One of his 6 kids and his one employee Curtis stayed after hours to make sure I could get my truck that night. I have been only once to SF Differentials, I honestly hope I don't have to go back.
Pros: Quick, honest
Cons: Bring a jacket if you have to wait around