Spring Seat Spacing for Upgrading to 5,200 lbs Axles on a 2006 Forest River Fifth Wheel

Question:

Hello, I am looking to upgrade the axles on my 2006 Forest River Fifth Wheel. It is a 8200 GVWR unit with 3500# axle. Through the years, the axles have sagged quite considerably. I see it as two options: Option 1: I replace the axles with new 3500# axles. Since I am so close to max capacity and the axles are currently bent, I would rather not go this route. Option 2: Step up to the next axle size, which should be a 5200# axle. This is my proffered path even if I have to modify some things. Fabrication/Installation is not the problem here as I have experience in both. My problem is your available axles dont seem to line up to current or upgraded axles. As I measured from the same side of spring seat, I get 68.5. The 5200# axle 8327816-EB, looks like the closest I can find.

asked by: Mark J

Expert Reply:

So long as your current axles are 86-1/2" from hub face to hub face the Dexter Trailer Axle w/ Electric Brakes - E-Z Lube - 6 on 5-1/2 Bolt Pattern item # 8327816-EB will work just great as an upgrade to your current 3,500 lbs axles. You will just need to cut off your current spring seats and install some new ones. I recommend the Spring Seat for Typical 5,200-lb to 7,200-lb, Round Trailer Axles with 3" Diameter item # TRSS300. I have attached a diagram of the dimensions so you can confirm you have the space to move your current spring seats.

You will also need to upgrade your suspension. If you would like to send in the spacing of your spring hangers I would be happy to make some recommendations. I have linked another diagram that will show the dimensions needed to find you some replacement springs.

expert reply by: Jerred H