I have a 2005 Pontiac Grand Prix gxp with recurring transmission trouble. The transmission has been replaced by GM at 50% cost and the same symptoms are occurring again. Failure is eminent. I have what most are calling the rev and clunk syndrome in my current transmission. My 50,000 mile warranty on the new transmission has just ran out, but I have records where complaints were filed with the dealer with nothing found. After doing some research I see that I am one of hundreds that have had this same problem. Help!

- Middletown, VA, USA

The contact owned a 2005 Pontiac Grand Prix. When the consumer exited the vehicle, it rolled backwards and crashed into another vehicle. The vehicle was taken to the dealer for diagnostic testing but the technicians were unable to diagnose the failure. The approximate failure mileage was 5,000. Updated 02/14/12

- St Simons Island, GA, USA

I have a 2005 Grand Prix gxp in which the transmission has failed. I took the vehicle in for service last year because it would hesitate from a stop and slam violently into first gear. At the time the dealer could not reproduce the concern and told me to bring it back when it got worse. My extended warranty that I purchased separately from gmpp expired on the 22nd of September. This is a dangerous flaw when you are unable to accelerate when pulling into traffic, especially on the gxp model which has over 300 horsepower and torque steer that is hard to control when it finally shifts into gear.

- Westland, MI, USA

Transmission slips or shutters from a stop, then slams into gear. Shift from 1st to 2nd is slow. Shifting manually works ok. This is a common problem with the GM 5.4L engine 4T65E-hd combination and has been happening nearly every time I drive the car. Local transmission dealer says he sees this all the time and is a known issue. This has been happening for quite some time, but because it started after the warranty expired the deal would not do anything.

- New Berlin, WI, USA

Transmission showing signs of failure despite using the best synthetic tranny oil and regular tranny oil changes. The car has only 117 000 kms and slams into gear after a slow start. Also shudders sometimes before a gear locks in. Apparently these are common problems that occur just before complete transmission failure.

- London, 00, USA

Transmission is slipping for several seconds, then catching with a sudden "thunk". apparently this is a common problem for GM cars (Pontiac Grand Prix gxp, Chevy Impala ss & Chevy Monte Carlo ss) equipped with an LS4 engine and transmission. This is a dangerous situation as it comes and goes without warning. Sometimes everything is fine, but if you are pulling out into traffic and the problem occurs without warning you may not be able to accelerate appropriately and result in a crash.

- East Lansing, MI, USA

Transmission on my 2005 Pontiac Grand Prix gxp failed on 11/23/09 at 94,622 miles. Car was brought to dave sinclair Buick/Pontiac/GMC and the transmission was replaced under warranty. The second transmission started bucking while going up hills at 120,000 miles. Took the car in at 120,703 to the same dealership. They said no problem was found with the transmission and it was in good condition. The transmission failed again at 124190 with less than 30,000 miles on it. Dave sinclair replaced the transmission for $2979.19. I have complained to GM district managers about this not being an isolated incident with these transmissions and that I should not be responsible for this replacement. There is an issue with the 4T65E-hd transmissions where there is not enough line pressure getting to the transmission due to a faulty transmission pan magnet under technical service bulletin number 08-07-30-040B from May 2009. Since my transmission was replaced well after that, my transmission should not have failed as the symptoms were exactly the same as what should happen with this issue. Furthermore, this new transmission is doing all the same things the old one started to do before it died. GM has denied my reimbursement claim 2 times and I have not stopped complaining. I am about to drop off my car for the third time in less than a month because dave sinclair has not resolved the issues with this new transmission. GM should recall this transmission and reimburse all people that have paid for replacements.

- Saint Louis, MO, USA

1. events leading up to failure = regular day-to-day vehicle use. 2. failure = transmission, when accelerating from a stop, transmission seems to slip and then slam into gear. Also, occasional hard slam into 2nd hear under part throttle. 3. what was done to correct failure = repair shop inspection with pan removed 1-year ago, nothing found. Problem still exists..

- Alexandria, VA, USA

Transmission faliure.

- Hampshire , IL, USA

My transmission has blown once, and the replacement (factory warranty) is acting up and getting ready to go again. (excessive slippage, grabbing, and fail to engage). I am not an aggressive or spirited driver, so there is no reason to have transmissions fail this often. In researching online, it appears this is common with this vehicle/engine combo.

- Rising Sun, MD, USA

My car at only 54K miles, transmission failed, causing to loose power in traffic. I had the transmission rebuilt ($2400), 8 months later it failed again ($1200), 2 months later, failed again ($0-warranty). Mechanic finally figured out it was some pressure relieve valve on the transmission, causing pressure to build up, causing the torque converter to explode, sending debris throughout the transmission. I did not go to dealer as car for that model year was out of warranty, but went to transmission shop who has been in business for about 30 years. I wrote to GM, but got no monetary satisfaction. Many people I've read about online with this type of transmission have had similar problems. I've never had transmission trouble in all the cars I've ever owned. It would seem there is a defect in this model, and would like to recoup the money spent on this issue. It seems it's on GM models with a V8 front wheel drive transmission. Like the Pontiac Grand Prix gxp, and Monte Carlo ss, Buick lucerne V8.

- Chesapeake, VA, USA

I own a 2005 Grand Prix gxp LS4 V8 with 60kmi. The transmission has shuddered on the 1-2 shift and sometimes delayed on the 2-3 shift since 40kmi. Every time I have taken the car in out of warranty, and even while it was in warranty, the problem could not be replicated. I know the 4T65E-hd transmission in this car is subject to failure as I am a member of many online forums that have cars with the LS4 V8 and 4T65E-hd and the transmission failure is the number one topic of discussion. It will leave you stranded without warning, and may break in the middle of traffic causing a dangerous situation to be in. It seems to be too much for a transmission that was designed to be mated to a V6 engine to be mated to a 5..3L V8.

- Oak Creek, WI, USA

The contact owns a 2005 Pontiac Grand Prix. The vehicle has been experiencing transmission failure since June of 2007. While driving 15 mph, the vehicle jerks into gear and surges unexpectedly, making it difficult to control. The contact took the vehicle to two different dealers because they could not determine the cause of the failure. The failure mileage was 23,000 and current mileage was 33,000.

- Brooklyn , NY, USA

I have a 2005 Pontiac Grand Prix sometimes when I press on the pedal the car hesitates. There is also a whining noise coming from under the car. At first I thought it needed a tune up so I had the spark plugs changed. I thought this would correct the problem, but the car continues to stall. Just the other day I was driving and the car would not go. It felt like the transmission was slipping. So I took it the shop and they said I have a problem with my transmission which I already knew that. I have talked to other people with this same car and they have also had transmission problems. I would like to know if Pontiac is aware of this or did I get a bad car.

- Nashville, TN, USA

I took my car in to an certified automotive center to receive a diagnostic check because the car had completely stopped on the bay bridge and I could not accelerate. Thank god I was completely over into the left hand lane because the steering wheel had completely locked. The automotive center could not find anything wrong but detected that the model and year had a recall on intergrated circuit chip damage that controlled the car. So they told me to go back to the dealership for that recall so when I went back to the dealer they stated that there was no recall. So I had to pay an additional fee to get my car checked by the dealer. Since I purchased this vehicle in July 2005 I have had several problems with transmission, sensors, fuel filter and had to put on rotors twice since I purchase my mileage is 69,000. I am asking for investigations on this car to see whether or not I was sold a lemon.

- Oakland, CA, USA

: the contact stated after accelerating to 65 mph to change lanes, the vehicle speed continued to increase after the foot of the contact was removed from the accelerator and began depressing the brake pedal. The tires continued to spin in a forward motion. The transmission was placed into neutral in order to stop the vehicle, but the engine continued to race until the engine was turned off. When the vehicle was restarted, the vehicle drove normally, but the brakes had been damaged when stopping the vehicle. The service dealer repaired the brakes, but was unable to detect the problem. The manufacturer was notified. The 3rd gear of the automatic transmission burned out, causing the vehicle to accelerate badly. The vehicle was serviced but the vehicle continued to have problems and stalled when the vehicle speed was reduced to 45 mph. The vehicle was coasted to a stop and then taken to the service dealer.

- Seabrook, NH, USA

: the contact stated while driving 45 mph, there was a long lag in the vehicle acceleration. The vehicle was pulled to shoulder, shut off, and restarted. When the vehicle was shifted into gear, it was not able to be moved in any direction. The vehicle was towed to a service dealer who was unable to determine the problem. Later on that same day, the same problem occurred a second time. The vehicle was taken to a second dealer who determined that the transmission had locked up due to the heat. The dealer informed the contact that they would be unable to repair the vehicle due to the contact purchasing the vehicle from a different dealer. The vehicle was then taken back to the original dealer, who rebuilt the automatic transmission. This was the third time the transmission had been rebuilt due to the same issue. Updated 10/17/2006 -

- Chicago, IL, USA

2005 Pontiac Grand Prix GT sedan VIN #[xxx] purchased 12/16/2004. Intermittently vehicle stalls/ loss of power in the engine. While driving the vehicle it will suddenly just loses power. You continue to press the accelerator pedal and then the engine will suddenly take back off at a great speed. This has happened while driving normally without trying to accelerate and also while trying to accelerate. The car has lost power while trying to merge in traffic. The car has lost power while trying to cross highways. The car has lost power while just driving down the road. GMC has performed the following repairs without fixing the problem. 12/30/2004 [xxx]-module, powertrain control-engine reprogramming. 01/24/2005 [xxx]-solenoid, pressure control-replaced. 02/04/2005 [xxx]-module, PCM/vcm-replaced. 02/14/2005 [xxx]-pedal, accelerator-replaced. Dealership purchased from capital Buick-Pontiac-GMC 225-293-3500. Dealership has advised that they do not know what is wrong with the car. We have been told that we have to go direct to Pontiac with the problem. Have been in contact with Pontiac since 02/15/05. Pontiac advised that they were going to research the problem and see if any other grand pri was reporting like problems. So far the only advice from Pontiac is they want us to come in and take another Grand Prix off the lot and see if we can get this car to duplicate the same problem. This did not impress me at all. So after waiting for 2-1/2 months for Pontiac to do something to fix the problem, I have decided to report this to NHTSA. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6)

- Baton Rouge, LA, USA