Periodic inspection of brake shoes, magnets and brake drum condition and bearings is wise & prudent. Failure of any of those things, at an unwanted time & place can ruin a trip or vacation in a hurry. Since inspection of those items requires removal of the brake drums, a new grease seal makes sense. In the past, I have seen roller bearings and races that are corroded as well as seals that are leaking getting grease on the inside of the drum and shoes. I'm leaning on new non-China bearings all around also.
The key idea is 'periodic' inspections. We are going into out fourth season with out 2016 HT 29.5 FBDS, so IMO, it's due. Doing a total inspection of the brakes, bearings with new double lip seals. Also plan on doing a wet bolt kit.
FAA licensed A&P aircraft mechanic, ex-RV dealer parts dept
Retired B-52 Gunner/Flight Examiner, B-52 Crew Chief
2016 Jayco Eagle HT 29.5 FBDS w/ 15,000 BTU AC, 50 amp service, upgraded counter top, thermal pane windows, elec. stab jacks, outside grill, backup camera and MORryde pin box.
2011 GMC 2500HD DURAMAX/ ALLISON