Took our 2008 T&C with 105,000 miles to Aamco for a full service just to keep up with maintenance. Less than 300 miles later started having trans issues.
Will run great but seems to be triggered by long idle times or stop and go traffic. Trans will not shift up out of 2nd (or possibly 3rd) gear. engine will just rev up and up. Tried shifting into manual shift mode but there was no option on the dash and sliding the shifter sideways didn't engage manual mode. As soon as I stop the van, turn it off, and turn it back on again, the van runs GREAT. Sometimes for only 10 miles or so before I have to do it again but sometimes it will go days.
Like I said, seems to be triggered during long idle times or stop and go traffic. I took it to a trans shop (not aamco) and he said I have low pressure inside the trans and it needs rebuilt/replaced.
I'm blown away that I can just restart the motor and it runs perfect so I am not willing to accept that diagnosis yet. Lol. I was a yamaha outboard tech for 6 years and I'm very mechanically inclined, but I am not experienced with transmissions.
Trans fluid is at the perfect level. Originally I was getting P1404, P0733, P0734, and P0792. I replaced the output shaft sensor as a cheap shot in the dark but no resluts. Now Im getting recurring codes P1404, C342D, P0733, with my harbor freight scanner. P0734 and P0792 are not recurring.
I have spent hours researching but I am not sure the next best route and I'm hoping to avoid a new trans if possible. Im considering changing the PCM, and then possibly solenoid pack if that doesnt work.
Any insights, information, or comments would be greatly appreciated. My growing family loves this van and would love to forego the expense of a trans overhaul. I thank you all for any knowledge you're willing to share.

 

... forgot to mention I was also considering pulling the compounder to check ring lands, clutches, and piston. I have read the compounder is culprit in many cases with symptoms like mine. Would love to know which direction is most appropriate before I commit any resources. Any helpful info is appreciated. Thank you ChryslerForum.

 

do you know what AFT4 smells like? does this new fluid they install smell like that?

 

I am not familiar with the ATF4 scent... but I must say I went and smelled the trans fluid after I read your post and it's got a pretty unique smell.

 

While on the topic, I also smelled the ATF in my 2003 toyota avalon which had a completely different scent. It's supposed to be Dexron VI in the toyota but I personally did not add the fluid so I am not positive that's what's in there.

 

What type of trans service was done? Was it a pan drop and filter replacement or a flush?

I suspect that aamco did not use atf+4. Still, a failure after only 300 miles is not typical even if the wrong trans fluid was used. It is too coincidental that the trans was serviced and a week or so later starts having issues.

My suggestion is to drop the trans pan and check for pieces in the pan. Replace the filter and refill with atf+4, 4-5 quarts ( walmart supertech atf+4 is the real deal and is a good price). May want to replace the trans pan with one that has a drain plug so you can do a number of drains and refills to get rid of what whatever aamco put in.

 

The service included dropping the pan, replacing the filter, hooking it up to a computer to confirm proper shift points (even though we had no performance complaints at the time.) It cost over $300. I agree the coincidence is very suspicious. I may stop by aamco to ask for a copy of my invoice to see what fluid they charged me for. Heavily considering draining and replacing with ATF+4 fluid. Thanks for the input.

 

So I found the receipt from our service at Aamco. They charged me $40 for 6 quarts of "full synthetic ATF". Perhaps this is not the proper ATF?

 

So I found the receipt from our service at Aamco. They charged me $40 for 6 quarts of "full synthetic ATF". Perhaps this is not the proper ATF?

 

I called Aamco to see which "full synthetic ATF" they used in my van. Service manager told me it was ATF+4 and he can tell because of the price per quart. I explained my drivability situation and mentioned that the pan has been leaking very slightly ever since the service (which it has). He offered to repair the leak and visually inspect inside while the pan is off. He thinks there is something clogging the filter since I am able to restart the van and the problem goes away. Scheduled an appointment for Monday. Will update thread with any helpful info. I still invite any helpful considerations that you may have!