Wrong Hubs?

[rkochanowicz]

My response...

While this addresses specs on the axle and bearings (that we already know), it still does not answer the matter that the hubs are deliberately being used in an application over their manufactured rated capacity of 3500# per axle.

Lippert may state that the hubs have “significant head room to achieve more than then standard 3500# rating”, but that seems to be an opinion. Nothing has been provided to support using these hubs in a capacity more than they are rated. “Significant head room” does not change the fact they are manufactured, produced and rated with a 3500# capacity per axle and only 1750# capacity per drum. There is a reason that these components have a rated capacity, it is not up for interpretation or opinion as to if they are sufficient and have "head room" to be used in an application above their rated capacity.

How can components only rated for 3500# of capacity “married” to a 4400# axle provide a GAWR of 4400#? The GAWR is composed of the capacity rating of the lowest rated component in the assembly.

If there had been a death or serious injury related to this failure, are you able to prove that these are correctly rated and are not being used over their rated capacity? I want that proof.

This is a safety issue.

The response did not answer my question.

Please show me where the manufacturer’s specs for these BD6553517 wheel hubs show them rated to be used in an application over 3500# per axle and 1750# per hub.

 

[danemayer]

Lippert Components certifies and warrants that the 6 on 5.50 hub drum isappropriate for use on an axle rated for 4400#.

Hi rkochanowicz,

Reading the Lippert response, it seems like they're being pretty clear that they certify and warrant the hub for this application, and they go on to give you quite a detailed answer from their engineering dep't.

 

[rkochanowicz]

If they really certify and warrant the hub, then why am I having to purchase a new hub and axle? There is less than 5000 miles on these, they have been greased and maintained and they are practically new.

Does Heartland or Lippert really know the supplier in China is manufacturing these hubs to support more than they are rated? If so, then wouldn't the manufacturer rate them with the correct increased capacity? The hubs are from China, do you really think these products are being over engineered? I would bet that there is not one extra gram of metal or one extra ounce of strength in them than the bare minimum to meet their rated capacity as manufactured. Lippert has not been able to provide me with any additional scientific or technical specs on the hubs from the manufacturer, other than their opinion that they will support increased loads over their maximum rated capacity. I am composing a letter to the NHTSA as well as others with the details to try and get an official determination as to the safety and legality of this. I am also trying to locate contact info for the Chinese manufacturer that brands these Axletek hubs to see if they also tell me it is ok to normally exceed their rated capacities by over 20% and accept that it will be safe and reliable. It seems that a mismatch of hubs that are not rated to support the rated loads of the axles and the GVWR could result in someone having an accident and getting hurt or killed.

The facts are that the hubs are rated by the manufacturer to support a capacity of only 3500# per axle and they were selected by Heartland / Lippert and used in an application of 4400# per axle. There is a reason that parts have a capacity rating that should not be exceeded. Using parts that are not rated to support the loads put on them and then saying it is OK to exceed the manufacturer's rating does not seem safe, or legal. Something is not right!





If these hubs are being