2007 Dodge Charger SRT8: DIY Front Brake Job
by Dan Edmunds, Director of Vehicle Testing on November 30, 2015
Pt 1 | Pt 2
Our 2007 Dodge Charger SRT8 needed front brakes. The pad wear indicators were not yet squealing, but the front pads were getting mighty thin and the pedal was getting long. Last time we had it in for service the dealer said they could replace the pads and rotors for an out-the door price of $695. That sounded steep, so we figured we might save some money and do it ourselves.
The Charger SRT8 features Brembo high-performance front calipers, which are more expensive to buy initially, but not that hard to service. These are four-piston fixed calipers, which means there are no sliding pins to inspect and lubricate. And we're not experiencing any complications. Our Charger isn't pulling to one side, there's no shudder that might indicate warped rotors, and the rotors themselves look quite smooth as viewed through the five-spoke wheels.
It was possible that we could get away with just a pad change.
So I went to my local Dodge dealer and asked for a set at the parts counter. The guy started to tell me something about the need to order them as he eyed the computer screen, but then stopped suddenly as if he'd just remembered something. Abruptly turning around where he stood, he reached into a box on the floor no more than two feet away and came up with a set of 2007 Charger SRT8 Brembo brake pads, just like that.
Apparently someone else ordered a set a few days before, but that customer wasn't due in until the weekend. He sold me that guy's pads and ordered in another set to replace them. I can only assume he knew he'd get the backfill set in time.
The high-po Brembo pads cost $121 or $130.68 with tax.
I finally got time to do the deed a week later. I drove the Charger home, parked it in front of my detached backyard garage, set the parking brake, jacked it up and set the front end on safety stands.
The SRT8's wheels use a rather open design, but I got a much better view of the rotors once the wheels were out of the picture. They were indeed smooth, and they certainly didn't look glazed, but the rotors showed sure signs of significant overall wear.
That's right: rotors wear down along with brake pads, especially when those pads employ a high-performance formulation with a high metallic content. Pads wear down more quickly, of course, but it's not all down to the relative softness of the two parts. Pads wear in a single concentrated spot the approximate size of a business card, whereas the wear area of a rotor is a donut-shaped ring with 10 times the surface area.
Brake pads typically aren't broad enough to span the entire machined surface of a rotor, so as the rotor wears, a telltale lip can be left behind at the inner and outer extremes. That was certainly the case here.
Now it was a matter of determining: (1) the minimum allowable rotor thickness and; (2) the actual working thickness of our rotors.
The minimum allowable rotor thickness is sometimes stamped onto the rotors somewhere, but not always. Third-party aftermarket rotors may not bother with that detail. There are two places to look: along the outer rim, or on the outer diameter of the hub or "hat" section. Our minimum thickness is 30.0 millimeters.
Even by eyeball, the height of the inner and outer lips suggested I would not like the measurement I made next. I don't have a pair of dial calipers, but with the simple tools I have on hand it was easy to determine that the rotor was at or slightly below 30 mm thick where the pads make contact.
Too thin. Time to put the brakes on this brake job.
I would have aborted the mission just the same even if I'd come up with a 30.5 mm measurement. These new pads will last tens of thousands of miles, after all. No use installing them on questionable rotors, even if they look smooth and aren't warped. And "turning the rotors" won't help in cases like this because that only makes them thinner.
Time to buy new ones. That was fine by me. I prefer new rotors to turned ones anyway. They cost a little more than machine-turning, but the extra thickness gives them superior thermal capacity, which means they'll have better fade resistance and will be less likely to warp. It's also far less time consuming to simply swap old for new.
Turning is far more compelling if you have an older car where the rotor, hub, wheel bearing and lug studs are a single part. Turning rotors was invented and encouraged because removing and replacing that type of old-school rotor was labor-intensive and messy. But modern cars are set up with hat-style rotors that are separate from the hub and slip over the lug studs with ridiculous ease.
I put the wheels back on, re-torqued the lugs and headed for the office. I detoured into a different Dodge dealer on my route and inquired about ordering some rotors. It was my lucky day. They had the special slotted Brembo/SRT8 ones I needed in stock for $129 each.
Soon I was out the door with a pair of the world's worst Frisbees (the 12,020-gram edition) after handing over $281.22. Total spend for pads and rotors was now up to $411.90, but compared to the dealer's $695 estimate, this DIY brake job would still save $283.10.
But the delay means I'll have to put off the actual work for another day.
Dan Edmunds, Director of Vehicle Testing