How do I find out the details of the various drive train components in my '99 K2500 Suburban. I bought it used with 233k miles. It is in great shape (rust-wise and mostly mechanically) and I have almost 250K on it now. I have a leak from the front differential front drive axle inner shaft seal, but I'm not sure which diff this truck has [8.25 Inch S4WD; 8.25 Inch F4WD; or the 9.25 Inch?] How do I determine which it is? I was hoping that the VIN number would help me get this info, but haven't been able to find it.

I'd also like to know which of the following this vehicle has:
-rear differential
-transfer case (if there are options)
-transmission
-(I know it has the Vortec 454 engine)

Where do I find this info?

Thanks!

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