We have a 2007 Monaco on a Roadmaster chassis and have just suffered a near miss – both rear trailing arms have hairline cracks at the point the arm attaches to the rear axel with sub 10K miles on the clock, they have just been replaced with the new upgraded units, and we did not suffer a failure of either whilst driving, the actual extent of the cracking is not yet known to me as I have not seen them for myself, that pleasure awaits me when I collect her from the dealers next week some time.
This thread is a note to ALL American RV owners that have an RV built on Roadmaster R4R and RR4R chassis equipped with the Monaco Gold (also known as R-Way) suspension. The problem does not seem to involve any Roadmaster R4R and RR4R chassis that are equipped with Neway or Reyco suspensions according to some articles, but I would recommend it is still worth checking your suspension anyway.
The affected chassis are from model year 2002 through to 2009 inclusive, I know it affects the following from the recall notices I have read; Monaco Knight to 2004, HR Ambassador to 2004, Cheetah to 2004, Monaco Cayman to 2009, HR Neptune to 2009 and all years of the Simba but can’t confirm that is the extent of the list.
Reading the US forums, it seems on average that around the 15K miles mark is the point at which they are failing, but some have failed well before and some have failed long after, the pictures below are from one of the documents I have found on the various forums stateside that carry this issue and shows the original inadequate arms vis-à-vis the new upgraded units.