Hey heavy, sorry to hear you're not getting as many replies as desired. I've had better luck with asking tow questions on truck related sites, some of those guys are virtual encyclopedias. I tow a ~ 2500 lb ski boat every weekend with a dual axle Magnum trailer with surge brakes... previously using my 1996 4.3L V6 Chevy Blazer and now using my '04 Sport V8 Runner. The differences were immediate and obvious - MUCH better brakes, and MUCH more torque. My only complaint, and it probably doesn't apply to you in the '98, is that the hill start assist sometimes makes terrible noises when it tries to hold a boat on a boat ramp. I have been assured multiple times that this is normal, but it still gives me the creeps. For a vehicle with the 7,000 lb advertised tow rating like mine (not sure what yours is, probably 5000 as you said?), the hill start assist should be bullet proof or have a manual shutoff. I'm guessing my load is approximately 3,000 - 3,500 lb w/equipment and gas, and my truck handles it very well over short trips in hilly country. Having a good turn radius such as we do with the Runner makes maneuvering and backing the trailer a joy compared to most full-sized pickups. As far as your situation goes, is it a dual axle trailer? Tongue weights should be less and handling would probably be better. I assume it has some kind of brakes with that much load? If you're pushing your towing limit, be very conscious of your reduced vehicle handling and your greatly increased stopping distances. This can be hard to impliment in the city, as people will constantly pull into the buffer zone that you're leaving in front of you.
Sorry for the rambling, hope it was some help. It would be very nice to have a dedicated towing thread on here...
Justin