When speaking about three tires on the ground and one 'hanging' in the air. While on Spring Break (this year) I had a bearing/brake/backing plate destruction on the back axle drivers side.... I drove down an Interstate in Spartans burg SC with one axle tow strapped up in the air for Eleven miles (11 Miles). Yes, this was a lot of stress on the remaining tire/wheel/spindle on that side, but I had no choice at the time. The axle specs are 4400 per axle. The Camping World Tech who worked on my unit the next day, ground on the spindle that had became egg shaped and beat on new bearings (also replacing a new hub/backing plate/brakes). The threads on the spindle were messed up and he beat the castle nut on and cotter keyed it with a large key. The tire/wheel looked to be just fine and was put back on. I have driven the unit about 1500 miles since that time and all four tires are the same and NONE seem to have any abnormal wear.
I replaced that bad back axle two weeks ago at my house. I placed boards 4 inches high at the front axle and drove up on them. The back axle tires were still on the ground, but a lot of pressure was taken off of them. I blocked up the frame behind the back axle to hold some weight. I took a jack a lifted one tire off the ground (had to go an inch) and pulled the tire/wheel off. Went to the other side and took that wheel off. With the back axle hanging by itself I was able to take it off easily.
I had talked to Lippert about up grading my axle(s) from a 4400 to a 5200 pound. The spindles on the 4400 "beam" are 'rated' at 3500 pounds. What makes the 4400 rating is that the beam size goes from 2 inch to 3inch. To go to a 'pure' 5200 pound axle rating, I would have change out the brakes/hubs/etc from 10 inches to 12 inch size and the cost would be very high to change out what I already had. To my surprise on reading the rating label on the new axle I just recieved, it said '5200' pound rating.... the 'beam' was still 3 inches and the spindle was still the 3500 bearing size, the 'upgrade' difference from my old axle to the new one was the 3-4 times (massive) the welding size that is holding the spindle to the beam. This axle manufacture date was several days after I ordered it from Lippert, so it was 'made' with 'me' in mind and what I had asked for in beefing the axle up.
2013 Forest River Salem Hemisphere SBT312QBUD
2001 CrewCab F-250 7.3 PowerStroke Diesel
SuperChip, BTS transmission, 6.0 Trans Cooler