I have a 2006 Pontiac Grand Prix gxp. I started having transmission problems last December. The car shudders horribly around 50 mph. Had the car to a few different GM dealerships. One claims they didn't find anything wrong. The other one felt the problem, replaced a solenoid and car continued to do it. At this point they claim there is nothing wrong even though the shudder is still there. Car was under warranty til March. No longer under warranty and is getting worse. I know of over 150 people with w-body V8 GM cars that have experienced trans. Problems. Why hasn't there been a federal investigation"??? I guess it may be because of the GM bailout" NHTSA, please launch an investigation and a recall!!!!! I guess you'll just wait until it causes more accidents and deaths! good job morons!! thanks for looking out for the people!

- Glenmoore, PA, USA

We have a 2006 Grand Prix gxp. The sight and sound of this machine is wonderful. The transmission issues make me want to drive this car up GM's, well U get the picture. It slams into first from a stop, slips when accelerating, and it has less than 70,000 miles on it. I have had this car into the dealer three times for the same problem while under warranty. One "overhaul" and two diagnostic checks later the problem is still there. The fluid was changed at 47,000 miles. I have heard it is a pressure valve problem but this fix will be on my dime, as it is out of warranty now. Way to go GM, another victim here.

- Tucson, AZ, USA

I have a 2006 Pontiac Grand Prix gxp with the 5.3L V8 engine. The car has less than 104,000 miles on it and the transmission does not always engage first gear when attempting to accelerate from a stop. When first gear finally engages it does so with a very physical banging feeling. Also, the transmission shifts extremely slowing from 2nd to 3rd gear at times. This is a major safety hazard when attempting to pull out in traffic, if you are giving yourself enough time to make a turn, and the transmission will not engage, and then forcefully does so, it could cause an accident that results in injury or even death. I know that my car is only one of very many w-body V8's that have/are experiencing transmission problems. We are forced to spend our money and hurt our credit to fix a transmission that should never have been put in the car to begin with. American cars should be built better than this! if the government won't hold GM accountable for this mess, more consumers will have the same problems that I and many others are experiencing.

- Ashwaubenon, WI, USA

My car slams into gear from a dead-stop. It grinds very loudly when then tcc is applied. Shifts hard and shakes very violently, sometimes to the point where it is almost undrivable. GM dealer refuses to acknowledge the problem because they don't want to fix it. They claimed the grinding noise is a tick or rattle caused by timing chain for the displacement on demand when the engine goes from 8 to 4 cylinders. The tsb only states it would make the noise when going from 8 to 4, not 4 to 8. my car only makes the noise when I'm on the throttle, so it would not be going into 4 cylinder mode. GM are a bunch of lying dirtbags who don't want to fix the problems they cause. They compromised the reliability of this transmission to make it shift smoother. I'm a member of an online forum of just the LS4/4T65E-hd fwd cars and there are over 138 people with these cars who had or are having transmission problems/failures. Why hasn't there been some kind of recall yet? this is certainly a big enough problem to warrant a recall!

- Glenmoore, PA, USA

2006 Pontiac Grand Prix gxp transmission failure at 60,000 and 100,000 miles.

- Cary, NC, USA

Transmission shudder at cruising speeds. Delay when leaving from dead stop. Car slams into gear hard. Grinding/crushing sound.

- Glenmoore, PA, USA

My transmission has not failed completely as of yet, but I am experiencing a lot of problems with it.the car shudders violently during acceleration. Sometimes more severe than others. Very noticeable loss of power. Had the transmission serviced and the fluid was almost black and there was a excessive amount of metal or tcc material in the bottom of the pan. Car just reached 65,000 miles.

- Glenmoore, PA, USA

Transmission failure, the transmission fails to fully engage in to any gear when it is supposed to, it will slip and catch from a stop, the torque converter fails to lock up and all gears slip under moderate to heavy acceleration.

- Las Vegas , NV, USA

No major events leading up to the failure, just average city/highway driving with little to no aggressive acceleration. Regular maintenance is always taken care of. The transmission in my 2006 Grand Prix gxp, with 88,000km, likes to slip every now and then and sometimes fails to accelerate until it the rpms reach about 1800, then it finally catches and pulls hard. This does not happen all the time, but I'm worried the transmission is taking damage everytime it does occur, and may eventually lead to a failure, possibly resulting in a crash. Nothing has been done yet to fix the problem, as it only happens a few times week, and my powertrain warranty has expired. I've done some research, and judging by my sources, the transmission mated to the 5.3L LS4 va front drive GM vehicles is rated at 280lb-ft of torque, while the motor is clearly advertised at 323lb-ft of torque. Thank you for your time.

- Windsor, 00, USA

I was just informed by the dealership on April 3 2010 that my transmission needs to be replaced in my 2006 Grand Prix, which I purchased new. This is a very disturbing discovery being that my car was brand new at the time of purchase and now needs an entirely new transmission. The incident that occurred which prompted me to take my car to the dealership happened appx 2 weeks ago when I tried to press the gas pedal and the car would not accelerate. Luckily, I was on a side street and not on a major highway which would have caused serious incidents. This is the only time this has happened and I have received no notifications through onstar that there is a problem with my transmission. So, I am concerned about this issue and wondered where I can seek assistance.

- Washington, DC, USA

The contact owns a 2006 Pontiac Grand Prix. While driving approximately 30 mph, the vehicle jerked and then stalled at a traffic light. She shifted the gear into park in order to restart the vehicle. Afterwards, the vehicle would not accelerate past ten mph. The vehicle was towed to a local repair shop and they stated that the transmission was defective. The vehicle was repaired. Approximately two months later, she noticed a loud noise and her vehicle was driven to a local repair shop. The mechanic informed her that there was a hole in the water pump that needed to be replaced. Four months later, the windows would not roll down. The vehicle was driven to a local repair shop and the mechanic reviewed a diagram of the vehicle. The diagram stated that the fuse for the window was not located in the proper place. The window has not been repaired. The dealer stated that the failure was not under warranty. The manufacturer has not been notified. The current mileage was 50,000 and failure mileage was 45,000.

- Los Angeles, CA, USA

Approx. One week of transmission trying to kick into next gear, then one day (after about 4 days of this occurring) transmission completely died. Able to put into drive but trans was not communicating with wheels (per onstar diagnostic report). Had to be towed to dealer who said that there were "several notes on computer system" and that the fluid was "burnt beyond recognition." Had car towed to a different shop w/ ase certified mechanic who said that while trans. Fluid was a little burnt, was not that bad. Either way, a new transmission is going to have to be put into car and there is a chance of this happening again. Pontiac/GM is aware of problem due to tsb's being put out for problem, but no recall has been issued yet. Refuse to purchase a 3-4K transmission for this problem to probably happen again before 60K miles.

- Elkton, MD, USA

Vehicle driven for 60,000 miles - 95% highway miles. Complete transmission failure - slipping and unable to drive, and oil pouring on ground. Walk home failure on highway. Pontiac representative indicated that this was "normal wear.

- Ann Arbor, MI, USA