* Check the sticker on the driver's side doorjamb: This sticker will list the GVWR.
* Consult the owner's manual: The owner's manual will also specify the GVWR.
* Look up the specifications online: Websites like Edmunds, Kelley Blue Book, or the Jeep website's archives might have the information, but you'll need to specify the exact model and options.
Without knowing the precise model of your 2008 Jeep Wrangler, I cannot provide the GVWR.