My TT is about 4500 Lbs, 22' and tandem axle. When unhitched and without the stabilizer jacks down: how much weight is required behind the rear axle to lift the tounge? When I had a popup this was...
Probably not an issue, unless you have a lot of beef in the back. 4500 lbs trailer should have about 540 lbs of tongue weight, which is significantly more than your pop up.