How does paying my total car loan off affect my credit?

I recently got another car because I was having trouble with my old car. We went through Wells Fargo Bank. But this time my grandmother with A1 credit signed for me and I was the cosigner. Last time it was just in her name alone. I was told that the loan payments would affect my credit the exact same way that it affects her credit even though Im just a cosigner. For example if the payments are on time both of our scores will increase the same way. And if the payments are late even though I just cosigned it will still impact my score like I was the actual signer. Anyway what I want to know is how does paying the total car loan affect my score. Will it increase my score more than me just making the monthly payments or will it be the same. I have a small settlement coming in. If I decide to pay 10 months worth of payments will it boost my score a little more? Just curious on whether or not paying it off up front will give me a better score. Or should I just pay it month to month like I have been doing. Any serious advice will help. Thanks in advance!