Expectations??

I have a 97 B2300 w/ 138,000 on it. I've had to do only basic repairs and service (oil, filters, brakes, etc.). It has a couple of little problems such as a vibration near the exhaust shield, check engine light's been on for about 40K...I'm just wondering if anyone knows what I should expect as the vehicle continues to age. Is there anything I should check into right away?

my 87 b2000 has over 192,000 it knocks a lill and the input bearings in the training need replaced and it needs a new carb, but other than that its a great truck and I drive it daily (pretty hard) just as it is. thease are great trucks! too bad there fords now.

http://www.cardomain.com/id/drpdmazda
still verry much in progress
(never ending but just started)