Without know exactly what weight capacity of double axles you have on your 2021 No Boundaries Forest River, I can confirm that the kit # BK3-210 that you referenced will only fits 7k axles.
One way you can confirm whether you have 7k axles on your trailer is by looking at the axle sticker. If that is unavailable, you can always measure your spindles with calipers and compare the measurements with the attached chart.
However, you most likely have 3500 pound axles. If this is the case,... view full answer...
You can use the Malone 2" Dual Purpose Hitch Receiver # MPG544 with your current hitch you'll just lose 50 percent of the hitch's tongue weight capacity. If you have to use any form of an adapter you're going to lose tongue weight capacity.
If you're looking for just a standard 8" extender you can use the Hitch Extender for 2" Trailer Hitches # 80307. This will fit into 2" trailer hitches, has a 300 lb tongue weight capacity, and a 3,500 GTW capacity. view full answer...
Go To Results