VIN# 1GNFK16Z92J10xxxx

From this I get that it's a 2002 Suburban, and AutoZone online lists two possible transmissions, either a 4L60-E or a 4L80-E. First question is which one does my neighbor have, and how can I know for certain.

The symptoms are that the vehicle works in 1st and 2nd, but on upshifting to 3rd, the transmission acts like it's in neutral, allowing the engine rpms to run up. I found a YouTube video that lists the "clutch 3-4 pack" as the most common point of failure on these transmissions, and the symptoms are identical to what my neighbor has. Second question is how can the transmission be diagnosed for certain. I don't want to pull off the transmission and buy a clutch rebuild kit, only to discover the problem is something else, like a bad solenoid.

Did some other research and learned that transmissions give OBD error codes, so I figure finding out if the vehicle has any transmission-related error codes is something that should be done early in the process.

Any other help, insight, advice, etc...?

Thanks in advance.

 

(Bump)

1. How can I tell which transmission this vehicle has?
2. Can the transmission be diagnosed without pulling it off?

Thanks in advance.

 

the 4l80 would be used in the 2500 chassis mated to a 6L engine. the 4l60 would be with a 5.3 engine and 1500 series chassis. they also can be identified by the shape of the trans oil pan.

you tube is probably correct; a flare in 3rd could very well mean the clutch pack is worn out. only way to tell is a tear down.

buy a new trans. trans rebuilding is not for a beginner. special tools are required. its a lot of work only to find you put something together wrong and have to take it back out.
what ever you decide you must replace or flush the trans cooler and lines before installing a new or rebuilt trans.