Your truck could be worth $10,000. Add the amount for repairs to that amount and you now have as much as $20,000 to put towards an new truck. A two year old diesel with +-20,000 miles can be purchased for $32,000 including a factory warranty for 100,000 miles. So you have to decide for $12,000 (the difference of $10,000 for old truck plus $10,000 for repairs minus the $32,000 for the new truck) are you willing to risk catastrophic failure of your old vehicle. For me, knowing the history of your vehicle, I would not take the risk.