How Does a High-Low Adapter Affect Trailer Hitch Weight Rating for Flat Towing

Question:

I am planning to tow my Ford Focus with my Class A motorhome. The car weighs about 3000lb and the hitch is rated for 5000lb so I should be good to go. But the hitch is about 10 inches above the tow bar connection points and I wonder if using such a long hitch reduces the tow rating for the same reasons that using hitch extenders does - leverage on the hitch assembly and lots of welded joints. Thank you.

asked by: Pete A

Expert Reply:

The high-low adapters that are made more for flat towing setups instead of towing a trailer, like the Roadmaster # RM-048-10 which has a 10-1/4" rise/drop, actually only decrease the tongue weight rating of your trailer hitch when you use it for an accessory like a bike rack. Since you will be using this adapter to flat tow your Ford Focus the weight rating of your trailer hitch won't be affected because your Focus completely supports itself.

The reason why extenders reduce weight ratings so dramatically when used for trailer towing applications is because part of the trailer weight (the tongue weight) is completely supported by the trailer hitch. This throws things off for trailer towing but not for flat towing.

expert reply by: Jon G