Hi tri3nity.
How much an installment loan helps is very dependent upon your credit history. If you already have an active install loan, it wont help much. However, if you dont, it will improve your credit mix. Potential creditors, particularly in a manual review of your CR, like to see a mix of your payment history on both revolving and installment.
Payment history counts on both, but %util levels on installments are not that important. Getting a new TL will also reduce your avg account age, so it is not a one-category consideration.
I would approach getting a new installment loan as financial decision rather than a FICO decision. If you need the loan, get it, but not simply for FICO reasons.