The Grand Cherokee was a more upscale, luxury vehicle. In certain years the 4.0 six was available in the Grand Cherokee. Other models had the 5.2 (318 magnum), the 5.9 (360 magnum), the 4.7 engine, and I think some of the newer ones had the 5.7 Hemi as well.

The Grand Cherokee is nicer than the regular Cherokee, but will most likely cost more to own. The regular Cherokee has a better repair record in most if not all model years. (In some model years it's MUCH better!) The Grand Cherokee with the 5.2 & 5.9's have a reputation for being gas hogs.

I own a regular Cherokee that has most of the bells and whistles found on the Grand Cherokee. The well equiped Cherokees aren't real common in this area, but can be found with a little searching. If it's going to be driven primarily on the road, I'd get one with the handling package. The easy way to identify these models is to look for a rear sway bar. Mine is an automatic. It has the transfer case that has full time and part time four wheel drive along with 2 wheel drive. On the winter roads around here, I really like the full time 4x4 option. In some areas that may not be an important consideration.