I did replace the original Shurflo Extreme Series (model 5900) and would just like to give some FYI for anyone that has the same model going dead.
First of all, the Extreme series even though it is one the Shurflo website, has been discontinued. The 5900 Extreme Series had a microprocessor and I feel that my pump simply went brain dead; possibly from a power surge. The Shurflo Revolution now replaces the Extreme series (model 4048-153). The pump change was easy and I have little experience with it at this point, since I am using external water. The Revolution has a internal bypass feature, which is adjustable and also an adjustable pressure setting.
I like add that FR parts had a very good price for the replacement at $134 as compared to $195 + tax from Camping World.
Gale & Hank- 2012 Berkshire 390BH