I have a 91' XLT with 125,000 miles on her.I do alot of beach buggying with it and really give the tranny a workout.Take tires down to about 18psi.I'm thinking of making the switch to syn. tranny and engine fluid.Anyone have experience with this? Pros & cons? Proper procedure?

I am an auto mechanic and I have some experience with synthetics. The synthetic tranny fluid is a good idea, but you need to get rid of as much of the old fluid as possible. This means dropping the trans pan, changing the filter, and draining the torque convertor. If you can find someone who will install the synthetic using one the newer trans flush machines, even better as it will save you the mess that comes with dropping the pan. Also, if you are working the tranny hard, you should make sure you have adequate cooling. If you don't have a tranny cooler mounted in front of the radiator, you should add one. As far as the engine oil goes, with 125k on the engine the benefits of changing to synthetic motor oil are limited. If you keep the oil changed on a regular basis, you don't really need the synthetic or synthetic blend oil. Just my $.02.