I have a 2009 GT and the steering actually seems "lighter" than the 2005 V6 I rented when a college committee I was serving in took a vacation. Especially noticeable when turning the wheel at a stop, as if to back out of a parking space. Perhaps a certain part or system was used on the earlier S197's? I'm not for sure.
Really the only thing I can think of that you can check is after you drive take off the oil cap and look for a milky yellow ring. Other than that everything else that you would want to check would be under the valve covers. If the car drives good and isn't knocking, ticking, or pinging then you can assume it's been taken care of. One of my GT's is approaching 200k and it's still in great shape. No signs of going out on me yet! Just make sure to take the beast up to redline a few times and get a couple of WOT shifts in. If it passes that test you got a winner.
If it doesn't have sensors anymore it would have to be the rear (downstream) sensors. The front (upstream) are required for the engine to function properly, so those are still there. You will have to check the codes but if it is an exhaust code you will likely have a O2 sensor slow circuit code (long tubes) or Catalyst system efficiency below threshold code (no catalytic converters). Neither code will effect drivability and both can be turned off with a tuner so you don't get the annoying check engine
light. Be sure to check the codes and make sure those are what you have on your hands before purchasing though.
Good luck buddy. Hope to see you back here soon.
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