Lousy Forest River support for buyers - Event Date: 21 Jul 2014

Well.. a 3500 pound axle.. is a 3500 pound axle. So unless you overload the trailer, the rating FR puts on it should be valid, yes? I suspect your aliner had the same axle because they only come in certain sizes, and that got them the cargo capacity + dry weight they wanted to use.. 

   I will try to explain as best as possible. The wheels were slanting in at the top and the cargo capacity numbers on the label from the factory were greater than the rating of the axle 3,500 lbs. The dealer made some phone calls and it was agreed that Forest River would replace the axle with the newer 4,400 axle with 15" wheels. When I arrived home from Alabama where I purchased the camper I found out Dometic had a kit to quite the AC under warranty. When I had it at Camping World it was brought up that one wheel was slanted inward on top and the other wheel was straight. It was looked at by a technician pictures were taken and manufacturer confirmed it was a bent axle so another axle was ordered with new tires. So we are now with a third axle one the original 3,500 lb. and two the replaced bent axle and the present axle. There were a lot of complaints with the Vibe having only a 3,500 lb. axle with little room for cargo weight and my guess it hurt in the number of Vibes sold. Now all the new Vibes have the 4,400 lb. axle. And I believe they are all Lippert axles. We only have about four miles on our new axle and tires so can not say if this axle will work well in the future but I am hoping it will and the first axle was a defective axle from the factory. 

   It's very hot to go camping locally but hoping in a month or two to be up in Tennessee for a couple weeks. I sometimes refer to our camper as the Tennessee Express we are often traveling back and forth.

   I believe you have a 3,500 lb. axle, if you look on the outside of your trailer I believe the left front side there will be a label with the GVWR subtract your factory tongue weight and that would be your axle weight limit. So if your GVWR is 3,900 lbs. and your factory tongue weight is 400 lbs. your axle limit would be 3,500 lbs.

My 2014 179 showed 3320 on the axle on a certified truck scale.  That is with full water, empty black and gray tanks and no clothes or food as would be packed for a trip.
Yes, pulling out of a campground with full black and gray and even if you emptied the fresh water during the stay-  you'd be over.  
  Some of the places I camp I have to go a long way to get to a dump station. 

Also consider if you use a WD hitch you "force" more weight onto the axle....