Cadillac CTS problem(s)

[STSJohn]

Ok,Well,I have 2 Problems

1) to open the trunk my my 04 CTS is getting to be a Pain in the A$$, It takes way more effort to open then it should and when I "pop" the trunk it doesn't even budge I have to physically go an lift it

2) I have been noticing a Whining/Howling sound coming form the rear end of the car when at highway speeds. My friend had a similar problem and it turned out to be the rear differentials is this a common problem with the CTS.

The car is still under factory Warranty, when I bring the car in I don't want them to tell me oh there is nothing wrong and its just my imagination, I would really like to get input from other CTS owners if this has happened to them?

Thank you in advance

[JimD]

There have been some differential problems reported and discussed on the two CTS forums at

http://cadillacforums.com/forums/

As I remember, CTS-V owners were reporting most of the noisy gear sets. GM is more than aware of the situation.

[BodybyFisher]

With regard to the trunk, I believe there is a pressurized strut(s) much like the hood that can go bad, it probably just needs to be replaced..

[Bruce Nunnally]

Apparently there is a 2006+ differential that is somewhat improved. Yes, this should be something the dealer is familiar with. I suspect they will immediately replace it without much discussion, or begin to give you a long discussion on how 'they all do that'. In the latter case, be polite yet firm, and persistent.

Still not clear what the issue with the differential is in the non-V CTS's. In the V's they sometimes break the differential casing or similar due to the wonderful torque in the LS6 or LS2 and wheelhop. This gear whining issue seems to me a separate problem. One supposition is that the fate of the differential to whine or not is related to how it was broken in, that first 500 miles of driving.

If you do get your differential replaced, it seems very important to follow the break-in procedure for the first 500 miles.

The trunk on my CTS does not flip up on opening, but just releases and I have to open it. I am not sure if you can adjust to some other setting.

[Bruce Nunnally]

Also, http://www.cadillacfaq.com has a list of CTS or STS TSB's. The only one I see that relates directly is this Preliminary Information:

Subject: Howl Whine Noise from Rear Axle - keywords accelerate decelerate

#PIP3051C - (07/13/2006)

Models: 2003-2007 Cadillac CTS

2004-2006 Cadillac SRX

2005-2007 Cadillac STS

2006-2007 Pontiac Solstice

2007 Saturn Sky

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Howl or whine noise from the rear axle on accel and/or decel. The noise is most noticeable at speeds between 35-50 mph (56-80 km/h).

Recommendation/Instructions:

Service Information

Compare the noise to another identically equipped vehicle with similar mileage and make any necessary repairs. Axle break in procedures must be strictly adhered to during initial break-in as outlined in the Owners Manual. This also applies to any replacement axles that would be installed in a customer's vehicle. For 500 miles (800 km), it is suggested that rapid acceleration be avoided, as well as to avoid driving at the same speed for more than five or ten minutes at a time. The vehicle should also not be used for towing during the break-in process.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition

exhibited is resolved without completing every step, the remaining steps do not need to be performed.

[STSJohn]

Thank you Bruce and everyone else. I took the car in and on Monday they are going to replace something with the trunk because they are shot and they may have to repalce the Rear. I will update when I know more

[Bruce Nunnally]

This site has a collection of links on differential complaints:

http://reardiff.jon04ctsv.com/

[STSJohn]

Well, just got the car back. The shop went ahead and replaced something in the trunk and the trunk no opens with ease they also replaced the rear with stronger 06 rear no questions asked. Hopefully I will have no more problems with the rear. Thanks everyone for the infomation you helped me with.