[crashz]

Donut gives good advice.

How does the fluid look on the dip stick? Clean, clear and pink/red is a good sign. Cloudy, brown and sludgy is not. If the fluid condition is poor, try dropping the pan. If its just brown, with slude in the pan (clutch material), clean it real well, clean the magnet (metal fuzz is normal, chuncks are not!), replace the filter and fill with new fluid. It wouldn't hurt to put a new pan with a drain plug on it so that you could periodically re-fresh the fluid. The TC holds the majority of fluid and a pan change only removes about a 3rd of the nasty old stuff. About 5 drain and fills will get about 95% of the old fluid out.

I'll add that if you do find a bunch of junk in the pan, don't fret to much. A good trans shop will likely be able to rebuild the TH350 for a very reasonable price (ie: probably the cheapest auto to rebuild on the planet!). If you do have to rebuild, do your self a favor and bypass the orginal trans cooler and add a new aux cooler instead. Seems like garbage left in the orginal coolers take out new rebuilds all the time, even when flushed out.