[special-K]

I see a difference between aftermarket "replacement" parts and aftermarket "upgrade" parts. Most parts I see listed here are upgrades, so not a fair comparison. Like the transmission pan. All the TH transmissions in vehicles I have owned performed just fine with the original stamped steel pan. These were sold as Chevrolets, not Mercedes Benzs. With budget in mind, these are some of the best built vehicles ever.

In the past I found OEM parts to be better than aftermarket and that's how I ended up buying up N.O.S. The things I found better than OEM were the typical service parts, like brake shoes/pads, plug wires, and I always used Standard Ignition's "Blue Streak" parts for tune-up. You could argue even those parts were upgrades. I have always stuck with AC spark plugs. Unless I was upgrading, I'd use GM parts to get the service I did from the original parts. I've had plenty of upgrade parts not hold up as well as the OEM as well.