joseph what are some of the things they said are bad in the trans??How many miles was on your car went the trans went.Thanks in advance

Alright guys, so instead of taking the 800 dollar plunge I decided to give Sea Foam Trans Tune a shot. It is different then other trans additives because it is specific for cleaning gum and varnish that occurs. I figured 9 dollars or 850, I'll try the 9 dollar and see if it works, if it doesn't well then I'm getting the repair anyway. So I followed the directions on the can, first though I pumped out some trans fluid so I wouldn't overfill. (While pumping out, fluid is red as ever and smells new.) THe directions say take a drive let it run through the trans, add to an operating temp trans as well. So before the additive it took about 20 mins then the hard shifts came. I just got back for a trip to San Diego, about 2.5 hours away, drove down no hard shifts even at stop lights and doing city driving, drove back today no issues to report. I'm not saying this magic juice is great, I typically do not add additives, but I thought it couldnt hurt. It worked for me, I had used sea foam products in the past for the boat and for the gas in my car. Good results, I will keep you updated if this keeps happening. I also talked with the trans shop and they said it was worth a try. These guys are very reputable also, so let me know any thoughts you have. Have a good one.

Adam

Great..let me know if the good results continue,Im so digusted in the transmission in this car.Hard to believe no recall on this,had many other stupid issues,gas gauge not working right ,climate control lights out,fuel pressure regulator leaking.Things that sdhould last at least 100,000 miles

So I took the Impala to the trans shop yesterday and here is what I got. The owner said that it is not my pressure control solenoid because that would trigger a engine light. He is telling me that it is my pressure control valve and that I need a valve body kit replacement. I looked online and called the parts shop, I cannot find a valve body kit. He is telling me that what is happening is that upon heating up it is staying open and that is where the hard shift comes from. I am wondering if what he is telling me is true, or if I should get a second opinion. He also said something about the aluminum bore and that if I let this go it with ruin the torque convertor. Any insight is helpful. The quote he is giving me is around 650-700 dollars. Also would a trans flush help this issue of the valve body? He also said this is mechanical not electrical. Thanks in advance, this you guys have been a huge help with this process.

I would get a 2nd opinion and have someone with a professional scan tool scan the system.
You may have a P1811, which will NOT set a check engine light.

No stored codes, no pending codes, had it scanned 3 times now. Does a stuck open valve sound like a culprit?

Im new to this forum and this is the first thread ive read. My opinion on this is I would repl the PCS and be done with it. I know you said no codes but I have seen many times where the cheaper code readers only show DTCs that are requesting the MIL which like stated before the P1811 will not do. IF you decide to let this trans shop replace the valve body make sure they get it from GM. There is a 2nd design VB and spacer plate that is being used on the 07 and earlier model year 4T65E in most vehicles. IMO though the PCS is the most likely cause here.

I have run transmission shops for 30+ years and have never heard of a "stuck open valve".

I say that you most likely have a defective pressure control solenoid as that is the most common failure on these transmissions with this type of problem.

If you hook up a pressure gauge to the main line pressure port, it should verify that the solenoid is the culprit.

If the pressure regulator valve stuck open, the car would not move.

I'm going to go to another shop for a 2nd opinion. I live in Southern Cal in the Mountains. Does anyone know of any good shops in the Redlands area? Also there is AAMCO, I know they are a national trans chain, anyone dealt with them? How are they? Any suggestions. I am from WI, but live here now so this is my first major car repair out here. Thanks again keep any suggestions or thoughts coming.

All AAMCO'* are independently owned. They could be very honest or very crooked. Go to someone who will not charge you for an initial diagnosis.