Good morning JVS. Welcome to the technical forum. This has been asked a lot on different types of travel trailer models in the past. If you don't get a specific answer on your particular model, I'd go with 24" which seems to be the norm.

Jim

If you have a late model HD Dodge truck, you will likely need a 6" drop.

All others are not so high and a 4" drop work for most GD trailers.

With the Hensley and Propride, its better to be a little high than low, different than what we're told for all other bumper pull towing. So if in doubt start with the 4" drop. Get it wrong, exchange is free BUT you pay for shipping.

Note, the ProPride has an adjustable stinger however Hensley vs ProPride is a personal choice. Their 4 bar pivot mechanism is 1:1 identical. Its other minor differences that set them apart for patent infringement reasons only, and the stinger is one of them. I have owned 3 Hensley's but will never say its better than the Propride and they have quality issues, I assure you. Still, all the Pro's and Con's equal out. Depends what is important you. Prices are nearly identical. Neither negotiate the last few years due to very high demand.