[Gatorguy18]

Hi All,

I bought my preowned '14 V-Sport Premium about 3 years ago and have added about 24k miles. Total miles now is about 43k.

Here's the issue, and it's happened twice to me now: After driving on the interstate at high rates of speed for at least 20-30 minutes, I'll start to feel a slight vibration/rough feeling and a low roaring sound coming from the rear. I think it's the rear passenger side. If I slow down to 70-80mph for a couple of minutes, the noise will stop and the ride will smooth out. When I stop, the right passenger rim is radiating heat and is too hot to touch. It's much hotter than the other rims, which are definitely warm. Does that sound like a wheel bearing going bad? I've experienced wheel bearings going bad on other vehicles, but the noise is usually more consistent and noticeable even at low speeds. Note: I've driven on the interstate several times between the two occurrences, but haven't noticed the issue. I think the difference may be the higher amount of time at a higher speed.

I've been reading some of these horror stories about the rear differential locking up (which I do NOT want to experience at high speed), but I'm not sure the early symptoms of that issue. What are the symptoms of a failing rear differential?

I have the GM extended warranty ($100 deductible I think), so I should probably take the car to the dealer, but I'm not sure they'll be able to reproduce the issue if they go up and down the local highway at 45-55mph.

Any thoughts (besides slow the hell down)?

 

[angel71rs]

Could be a bearing, or a stuck brake caliper constantly applying the pads to the rotors. Also could be stuck parking brake mechanism. I'd get it up in the air, give wheel a spin and see if you get grumbling or scraping noises.

I've seen the threads on diffs locking up or even cracking open like an egg on Vsports, don't think you have that as I am of the opinion that those are due to internal diff component failures. If you had something diff internal failing, heat would be in the pumpkin not the wheel IMO.

 

[TorontoCTSVSport]

Sounds to me like a caliper that's stuck. Same thing happened to me and I replaced both rear calipers, rotors and pads when I saw that the inside pad on the drivers side was metal on metal.
Once you've got it on a hoist, you will be able to tell almost immediately without even having to pull the brakes apart.
Get this taken care of before it damages the wheel.
Eventually the worn out pad will start to grind the metal of the rotor. This will spray the wheel with hot metal filings that will embed themselves in the finish. At some point all of this heat will start to discolor the wheel as well.

 

[Gatorguy18]

Thanks for the feedback. The sticking caliper seems viable. The issue has happened only twice. It definitely doesn't happen each time I drive. In fact, I drove similarly the day after I posted and the issues didn't happen while driving and when I stopped, the rims all felt normal temp.

When you guys changed your brake pads, did you go OEM or aftermarket on pads? I definitely don't want less performance than OEM. Either way, sounds like an expensive job to replace calipers, rotors and pads! Yikes. I doubt this is anything that's covered under the warranty... or would the sticking caliper be covered but not the pads?

 

[TorontoCTSVSport]

Exact same thing was happening to me. It was intermittent. Likely because the piston would pop back into its correct position every now and again.
I went with OE calipers, rotors and pads as they were all pretty reasonably priced on RockAuto (although parts for this car are ridiculous compared to my wife's Audi S3).
My front rotors are warped really badly now and it seems as though OE parts at RockAuto are getting out of hand so I will likely go with the Brembo parts (the actual manufacturer for GM on the front anyway). Delco Professional pads are showing $250-ish for the front (CAD) and the Brembo's are $53 right now.
As for the calipers, I would stick with OE. I had looked briefly into upgrading to rear Brembo calipers from a Camaro or CTS-V but it doesn't appear as though they will fit without several other modifications. In addition to that, it would change the brake bias so I would also need to upgrade the fronts to a larger set to keep things balanced/consistent with the factory setup. It would involve a lot of calculations (fluid volume, pad/rotor surface area, etc.) and likely a lot of re-jigging things in the front AND rear so I decided not to even go down that path.
In addition to that, our car was tested and tuned by Cadillac on a track so I'm confident the factory brakes are good enough for me as a daily driver.
You can get away with replacing the one caliper but I'd do them both while the tech (or you) is in there and replacing rotors and pads anyway. It's one less thing to worry about a couple months from now. If the other seizes, it'll likely damage the new rotors and require replacing them AGAIN.

 

[Gatorguy18]

Sounds like your thinking is right in line with what I was thinking. I figured GM used better than average braking components, so I didn't want to go aftermarket and get less performance. I'll have to do some research on getting some parts.

Is it normal to have to replace calipers/rotors/pads at 43k miles? I can understand pads, but I kinda thought calipers would last longer.

 

[TorontoCTSVSport]

I'm in sales and do about 50,000km (just over 31,000mi.) per year.
The CTS VSport is probably one of the worst cars I've had for frequency of requiring brake work.
I'm usually doing a full brake job every year to year and a half. These pads are pretty aggressive and tend to really wear into the rotor. You can see a pretty thick lip on the edge of my rotors and they're maybe a year and 3 months old.
The caliper has only happened once and I haven't heard of any other instances of this so I think you and I are just unlucky. I just hope you caught yours before chewing up a rotor and damaging your wheel like I did. I also cooked the brake fluid so had that flushed as well. Luckily when this happened to me, I was on my winter tires so the wheel that was slightly discolored was a shitty winter one.

 

[Gatorguy18]

I'm in central Florida, so I don't know much about winter tires! ??

Sounds like I need to get a brake job done. Now I just need to decide if I'm going to do it myself or have the stealership do it. I'll probably do it myself as long as they won't give me hell about my extended warranty if something goes wrong somewhere else in the car.

Meanwhile, I guess we all get to keep an eye on this new rear diff recall. Fun times!

 

[TorontoCTSVSport]

Before you get into it, just know that the Brembo calipers come off differently than typical calipers. You need a punch to hammer out 2 pins that hold everything in place as the pads and rotors "float". Then you need a tool that will compress BOTH opposing pistons in the caliper. A piece of wood or the old pads and some channel lock pliers will not work.
I haven't paid too much attention to it when the shop does it. While I've got a reasonable amount of knowhow and all the right tools, I've opted not to dick around with them for fear of screwing something up. I'm also getting lazier in my older age. HAHA

 

[TorontoCTSVSport]

Update on the brakes. I had decided to go with Raybestos rotors which were showing on RockAuto for our car. Unfortunately, their slotted R-300 high carbon steel performance rotors (which appear to be identical to the Delco Police/Heavy Duty Rotor - which, incidentally, is ALSO shown as a fit for our car on RockAuto) DO NOT fit on our car. All of the measurements are the same except for the "hat height" of the rotor. They're 5mm too short and will not align properly with the caliper when you try to install everything.
I'm now in a fight with RockAuto as they refuse to take them back despite the fact that they've advertised the rotors as being a fit for our car when they are not.
I found that Amazon Canada was actually the same price for the OE rotor PLUS free shipping where I would have to pay almost $100 for shipping for the two rotors from RockAuto. Sadly, Amazon only had one so I ordered it and will likely pay a small fortune to get the other from a dealer or parts supplier in town.
Hopefully Amazon Canada starts to build a car parts inventory similar to that found in their US operation. Until now it's been pretty much non-existent.
This is the second time I've gotten in a dispute with Rock for supplying parts that do not actually fit the vehicle in question.

 

[Gatorguy18]

I consider myself to be above average on mechanical abilities, but when it comes to brakes I kinda lean toward leaving it to professionals. Then the issue becomes, where to find a "professional". I think sometimes the guys at the shop don't care as much and/or don't have the proper abilities themselves.

I hope Rock does the right thing and takes back the parts they sold with an improper description. It only seems right for them to do so.

 

[FTSS]

Stick your ground with RA. It took persistence of several messages using orderly logical stern resolve to get satisfactory settlement for 2 clearly mismatched brake drums (different casting, ribbing, casting no's, milling pattern, even weight) Their argument held that all that (including entirely different casting numbers and weight) were all just 'visual differences', and that as long as they 'fit on the car' there was no requirement to accept return. Nope, I claimed a safety issue with something as critical as brakes you never mix parts on the same axle.

Be mindful I was told by a serv. tech. there that competition has resulted in lowered service, even to the extent of my having been shipped a boxed gasket set with a hole out of one corner and penned note, "Part Missing" right on the box. lol
Perhaps research the manuf. site to confirm application(s) in case you can validate a clearly incorrect RA listing.

And Gator- I can appreciate your perspective to side with 'professionals' for something as critical as brakes, steering...... However, given my observations over the decades of shop's work on others' cars (and some interesting painful stories) I've ended up with the exact opposite conviction of doing ALL work myself for greatest peace of mind for safety for me and my family. Vive le Differanse

 

[TorontoCTSVSport]

They actually responded favorably to my strongly worded e-mail and accepted the return ALONG with covering the freight for the return. I take back everything I said about RA. HAHA
Last time I got into this fight, I had to cover freight back... on a set of fog lights for my G8 GT. The cost of shipping almost negated the refund but at that point it was a "principle thing" for me.

 

[Gatorguy18]

Good news!!