[olddog]

Aluminum like any metal, has properties that are different than cast iron. Some good; some bad. Light is good. Way more thermal expansion is bad. So there will be advantages that can used and disadvantages that will need to be mitigated in some way. Ok enough theoretical babble....

Ford sure did make a lot of all aluminum Modular 4.6 engines for Lincoln's to Mustang Cobra's. I pulled a Lincoln down that had 105K miles on it. There was no ridge at the top of the cylinder and the cross hatch looked like it was just honed. They use ductil iron sleeves and low tention rings. If it wasn't for a broken valve spring (dropped valve into a piston), I think it could easily went 200K miles.

I doubt an aluminum FE is going to need a rebuild at 8K miles, just because it was aluminum. I would ask this guy, what are the simptoms that indicates in needs rebuilt, and what parts are they measuring the wear on?