Yes, but it is a special type of Will commonly referred to as a "Pour-Over Will" that works in conjunction with your trust. A Pour-Over Will acts as a safety net to place the assets that you did not transfer to the trust during your lifetime (most commonly things like your car and checking account) into the trust when you die. As long as the assets outside the trust do not exceed $20,000 in real estate or $100,000 in titled personal property, the Pour-Over Will does not have to go through probate when you die.

Of course, you may transfer your car to the trust (by going to the DMV or AAA if you belong) during your lifetime as well as your checking account (if you want to sign every check as trustee of your trust) but most people choose to avoid the extra time that would be spent in doing this since in most cases, the cars and checking accounts are worth less than $100,000 anyway.