2007 Dodge Charger SRT8: Its Dampers Are Tired
August 11, 2015
My fellow editor Josh Sadlier is correct that the big sedan is nicely devoid of squeaks and rattles, but "tight" isn't how I'd describe the current state of its dampers.
With about 70,000 miles on the clock, it isn't terribly surprising that its dampers could stand to be replaced. There's a general sense of looseness in how it traverses roads with bumps. It's not a floaty mess, but it's definitely lost some control.
It's now noticeably underdamped during rebound, when the body and wheels move in opposite directions. Most of all, though, is that the rear gets into its bump stops more than it should. And there's more going on here than just tired dampers.
The rear end of the Charger is equipped with Nivomat dampers. These clever bits supply a passive ride height-leveling function in addition to damper force. Neat! However, they also supply some ~25-percent of the total spring rate, too. So when the Nivomats get tired, the associated reduction in spring rate means you lose even more of the suspension's ability to resist getting into the bump stops.
I suppose that with the loss of some of the effective spring rate that the rear ride height would drop a bit too, but if it's happened here, the droop hasn't been enough to really notice. Yet.
The dampers aren't totally shot, but if it were my car, I'd definitely look into swapping in some new Nivomats for the spring rate advantage described above, rather than some standard aftermarket shock.
Jason Kavanagh, Engineering Editor