Best thing to do is figure out the actual tw. Is the 5500lbs scaled weight, or estimated? Follow my signature link for the CAT Scale how to, and stop by the nearest one for 3 seperate weights.
Going by the 5500lbs loaded weight, if you have the average 12-15% tw you could have 660lbs- 825lbs. Based on that I would suggest the 1k lb bars, regardless of what tv you have. You should size the wd bars to the actual loaded tw.