No car is fallible. No matter how careful you are, no matter how much or how little you drive it, sooner or later the pile of parts that you cruise around in will have a fault that needs attending to. All you can do is preventative maintenance and hope that it’s enough. In the case of our 2006 Chrysler 300C, we’ve been lucky…for as many miles as we’ve put on the car and how “gentle” we drive it, very little has genuinely broken. We’ve upgraded, yes. We’ve dealt with factory recall items, yes. But outside of the occasional tie-rod end or torsion strut bushing, overall Grandpa has been really, really solid and stand-up. That is, until Tuesday evening. I had to make a drive into Tennessee that evening and was looking forward to some sunset cruising with Grandpa. I went out, started it up and let the car warm up (and let the air conditioning do it’s magic inside), but when I went to shift into Reverse…nothing. The shift lever would move to the right, but it would not, under any circumstance, move down. Since time was not on my side, I left Grandpa and instead borrowed my wife’s truck to make the drive instead.

So what happened inside of the shifter that caused the Chrysler to leave me high and dry? One cheap little pink plastic part, the shift interlock, had failed…more exactly, the tiny little plastic hook on the “pink thingy” that a spring loops had finally failed after eleven years of use. Now, I could’ve actually driven the car if I had taken a moment and looked up how to manually manipulate the lockout, but that’s only a temporary deal. We needed to get Grandpa shifting like he used to, because nobody likes it when they can’t get their lever in gear.

We will show you how to fix the issue yourself, should you chose. However, we will spare you the cost altogether: Customer Satisfaction Notification K39 covers 2005-07 Chrysler 300, Dodge Charger and Dodge Magnums with floor shifters for this specific thing. Call your dealer and see if your car is covered before you hit the parts store.

Here’s the entire shifter unit for the NAG-1, out of the car. Loosen up the console and shift it back, remove the four 10mm nuts holding down the shifter, disconnect the two electrical plugs, disconnect the shift interlock cable and the shift linkage, remove the carpet hold-down pin in the driver’s side of the unit, and it’s out of the car.

Looking at the front of the shifter showcases the offending interlock (red circle). If your Magnum, Charger or 300 refuses to shift, you can remove the trim rings and jam your finger in that opening to manually move the interlock backwards, which will allow the shifter to move. Keep your jokes to yourself.

Here is a side-by-side of the standard interlock (pink plastic) with Dorman p/n 924-706 (aluminum). As you can see, the spring hook on the factory unit has finally snapped, which sent the spring flying inside of the shifter housing. No spring tension means the interlock won’t move without help.

There are tabs all the way around the shifter housing…just push them in and work around the perimeter and you’ll free the housing from the base. After that, all you have to do is pull out the “pink thingy” and put in the new unit, and reconnect the spring. Note the section of the interlock towards the left…there is a notch in the base of the shifter that the interlock needs to be fit into properly before you start reassembly.

While you have everything apart, now would be a good time to do some cleaning. Years of fast-food crumbs, dust, dirt and a quick bout with cat piddle necessitated some extra scrubbing.

Before putting all of the interior back together, make sure you do a functions test. Reconnect the shift linkage, the brake interlock cable, and both electronic connectors and start the car. You should have full function from the shifter, including the AutoStick functions. If all checks out, continue reassembly. With hand tools and a break for cleaning, the total time from start to finish was about an hour, and the Dorman part was about $33.