I have a 1992 RS with a 305 engine & 4L60 transmission.

How can i tell if the engine & transmission are the original ones or if they've been replaced?

Also, what is the maximum odometer mileage that you guys have gotten with this style of engine?

Right now i'm at 251,000 miles on mine & i've had it for over 10 years, & it's still running smoothly.

 

there is a pad on the front passenger side of the engine block.. right above where the water pump bolts to it.. if it's the original engine, the last 7 or so digits of the VIN will be stamped there... there is also a pad somewhere on the trans case with the same thing..

as to how far it can go, a properly maintained and nicely driven small block can go for a long, long time.. i had a 94 Suburban a couple of years ago that had 345,000 miles on it and it still had the original engine and trans in it and it didn't look like anything had ever been apart on it.

 

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http://texasz.net/allan_and_rosanne/...20A%204L60.htm