Replacement Grease Seal for National 412920 on Heartland 5th Wheel Trailer

Updated 11/20/2017 | Published 11/18/2017

Question:

No number on old seals, replaced with National 412920. $27.per seal! After Harvey Hurricane, wheels were under water. Grease washed out on to concrete. So, am I using the right seals? I have a Heartland Landmarkinch 5th wheel. 2005. 7000 pound axles. I have your electric trailer brake kit on order, just dont know what seals to order. Right now the wheel is not apart so I cant measure, hoping you could tell me. I thought the National seals were supposed to be the best. They sure are proud of them. When the wheels go completely under water, should the grease have washed out? Im told seals are designed to keep grease in,not to keep water out. Thanks

asked by: Russ P

Helpful Expert Reply:

For a grease seal that will replace your existing National 412920, you can use the TruRyde Grease Seals # RG06-070. These feature the same inner and outer diameter as the National model that you referenced and will work well. This seal is also typically found on 7,000 pound axles like what your trailer has, so this should be the correct size.

A grease seal is designed to help prevent water and dirt from entering the hubs, while providing protection against bearing failure. With this in mind, something like what you experienced with the wheels completely submersed in water for an extensive period of time, a grease seal probably will not provide enough protection against failure. This is likely why the grease from the hubs spilled out onto the concrete.

expert reply by: Chris R