I pulled 3 different 5 wheels with a half ton, the last a 27.5 Cougar RL and it did the job. Slowed on hills and in a head wind but otherwise no handling issues. then went to a diesel duramax and OMG heaven for power.
Best set up withe half ton was a Trail Lite 30ft which had a dry weight of under 6000lbs. Worked great as a unit with the 1500 ext cab with 5.3litre
2013 Crossroads Provincial CF345RF Full Paint loaded
2006 GMC Crew Cab Dura Max Diesel
I had every intention to tow a 5er with my EB but once we looked at the units available in that weight range we felt they were all too small. Pin weight was the deciding factor. And don't forget to include the 250lbs or so for the hitch in the bed. We went with a much bigger TT.
I have hauled two different 5th wheels with half tons, the first was with a ford V6 4x4 auto reg cab long box, trailer was 21.5 feet...no problems
Second was a 24 ft pulled with Chev ext cab 4x4 5.3 v8 and again no problems
Both of my trailers had brakes so I didn't rely on just truck brakes and neither truck needed air bags to help out