We thought we had Monroes on our 06 Monterey, since there was a time period where the factory switched brands, but the techs at Bend found some shock mounting issues were the real culprit behind our vibrations, and we in fact had Bilsteins - without a closeup look, the two brands appear the same color.
Some Goodyear tires were mismounted on coaches at the Monaco factory, which caused symptoms identical to an out-of-round condition. Thinking that was also part of our issue, we took the coach to Goodyear who determined the tires were mounted correctly, but Les Schwab in Redmond had improperly balanced both front wheel/tires. Goodyear's higher-tech balancer helped restore the ride an 11000 mile coach should have.
Prior to this, we struggled with switching to spendy Kuni shocks, since we thought we had Monroes and wanted to get either Bilsteins or Kunis to correct our vibration problem; but now our current Bilstein ride is fine, so we'll stick with them. In the interim we'd been advised Kunis were slightly better than Bilsteins, depending on who you talked to. But some said the difference wasn't worth the cost of changing, esp. after we found out we didn't have Monroes to begin with.
I guess the point is that ride problems should not be too quickly ascribed to shocks, though your porpoising is not a hard diagnosis.
