I am looking at buying a used 1983-84 Eldorado but have read some things about the reliability of the aluminum engine. Any thoughts? Thanks.aluminum engines are used to save weight and help increase horsepower, I don\'t think that making an engine from aluminum is a bad thing, the biggest problem is making sure you NEVER EVER OVERHEAT IT. They use steel sleeves in the piston bores and other critical high stress areas, but the biggest problem is once overheated its done, vaporized aluminum is actually very explosive too, Any Eldorado\'s still around from 84 now, I think has a good engine in it. another potential problem is spark plug removal and installation, using an anti seize is recommended. If you do find an Eldorado\'s now, someone may have installed a iron block in it anyway, because one thing aluminum motors are known for, is being very expensive.1984 Cadillac Eldorado1984 CadillacOther related question