I have the opportunity to buy an 84 or 85 Chevy 1 ton pickup with the 6.2 diesel motor. Some have told me that the mid-80's were not good years for diesels for Chevy. Is that true, & what's the reputation of them, how good are they, & do they hold up? This one has had minimal work done to it as needed, & has 92,000 on the odometer. Thanks for any input!