i have 96 rr SE 4.0 and i am looking into buying a 99 HSE. is there i big difference in MPG and performance?

 

I believe '99 is when Bosch Engine Control Management was introduced, but I'm not certain. Also, there is not MUCH difference in the SE and HSE. If you are looking at a '99 HSE then it will be the 4.6 and not the base 4.0, but the other addtions you get with the HSE are there, but fairly minor. I think you get like leather wrapped gear shift, and maybe more wood grain than the SE, and maybe different interior leather color options.