Hi Folks,
I’m looking for some honest opinions here:
I bought my new 2014 Challenger R/T in late June 2014 from Bill Luke in Phoenix, AZ. At about the 400 mile mark it developed a lot of noise out of the rear end. Mainly:
-Hard clunking when shifting 1-2 and 2-3 or when disengaging the clutch at low speeds.
-Strange “gurgling” noise between 30-50 MPH with little or neutral load
-Slight whine at freeway cruising speeds.
I took the car in to the Bill Luke service department and they test drove it and said the noises were normal. The let me drive an SRT8 which did indeed have drivetrain noise but overall the noises in that car were not nearly as bad as mine.
At the 1000 mile mark I installed 75W-90 Royall Purple differential fluid which did not help. The noises are always the worst when the differential is warmed up.
A few weeks later while driving on the freeway the car basically died and I had to limp it off the road. It stayed in some sort of limp mode and I was not too far from the dealer so I limped it in. They diagnosed that the throttle body was bad and would have to get one in from LA which would take a few days. They put me in a rental car (I acknowledge this courtesy on their part since I did not have the extended warranty on the car). After two weeks of changing parts (throttle body, pedal assembly and PCM) they determined that there was a problem in the wiring harness. They discovered that the 5 V reference circuit shared by the throttle body and other components had an open somewhere and that a junction point for this circuit was bad. They re-did the junction joint and ran a bypass wire for the throttle body 5 V wire. I told them a patch was not acceptable but they said it was. I feel this is not acceptable because the double defect with the 5 V ref circuit is only one manifestation of potentially greater defects within the harness and the only prudent thing to do would be to replace the whole harness especially considering car safety systems which could be impacted by a known defective harness.
In the meantime the rear end noise was starting to drive me and my wife crazy so I decided to investigate further myself and I took a video and measurement of the noise and backlash. I slightly loaded the drivetrain against the parking break and released then clutch in the one video. Videos here:
I realize that taking the backlash measurement at the coupler is not a true measure of the backlash at the pitch diameters of the gear set but this is the only thing you can do with the differential installed. I measured over .035” at the coupler bolts which is really excessive even if the working diameter at the dial indicator point is a little greater than the pitch diameter of the pinion considering a normal backlash amount is about .008” to .010”. The car has less than 2500 miles on it.
So I took the car back to the dealer this week. They got the district service manager involved as well as Chrysler engineers and they all say these sounds are normal (I provided them with the above videos). I told them I didn’t want an opinion or subjective diagnosis but rather specified service limits for the backlash to compare against measured values. They said they didn’t have service limit data but they would look into what they could get. I told them I wasn’t going to accept the car until they could show that the backlash was within service limits. The service manager stated that if I did not accept the car he would have it impounded. I walked away and got a ride home (I had to turn the rental in). So….questions for this board:
-Has anyone else experienced these differential noises? Are these really considered normal? I’ve owned several cars including IRS Corvettes and while they all have some inherent mechanical noise/clunking I have never heard anything near what this Challenger has.
-Does anyone have the backlash service limits for this differential? I believe it is the 3.06 (base) Getrag 226 mm LSD unit.
-Does anyone have the working/pitch diameters for this differential? The service limit backlash at the coupler can be calculated if these (specifically the pinion) are known.
-Other opinions?
Thanks,
Billy

 

We have the 3.07 differential. Try shimming, or have the dealer shim it to 3.07; providing you have the 3.06.

* The whine is normal, according to FCA.

 

 

I don't think you're going to get an accurate backlash reading at a rubber coupler


Why the hell won't they just check the diff backlash at the dealer? Or just put a diff in it? gees!


Seeing that it had 400 miles on it when you bought it makes me think someone did some epic joy-riding in it beforehand.


The wiring thing bothers me. I see lemon in your future. Maybe that's the way you should go..a buy back.

 

I agree with that, but that diff is not right.

There is way too much slop at the spider/side gears, and way to much backlash in the R&P.

 

Hi, yep I agree the measurement at the coupler is not a true backlash measurement but at least it is an indication.

I got the car with only 12 or so miles on it so I doubt if joy riding is the culprit though even in 12 miles someone could have done something stupid. Looking at the wear on the pinion teeth and the fact it went from no noise to lots of noise in 400 miles makes me think the pinion depth and R&P backlash was not set up correctly from the factory and it wore through a bad contact pattern and all the subsequent hammering has damaged something in the spider/carrier assembly.

Part of the problem is that these units are not really serviceable and from what I understand the dealers just replace the whole thing.

I think the local dealer folks were actually more sympathetic to my situation but the district service manager who they had to get involved made the decision that they would not do anything more to fix the harness or differential.

I've got an attorney and we are trying to negotiate a settlement but I'm about at the end of my patience with Chrysler and ready to sue as a last resort. I've not been able to drive the car for several weeks now as I believe it is not safe to be on the road.

Thanks,
Billy

 

I forgot to ask but do you work for a dealer?

Thanks again,

Billy

 

I do. YW.


Yes, as sloppy as that thing seems I would be worried it might try and lock up after it got hot