Everytime when the engine/trans is cold, the first 3-4 shift produces a shudder/vibration as the trans is shifting. Sometimes happens when the car is warm too. Ie. it's been sitting for 5-10min, again first 3-4 shift. After the first 3-4 shift, no problem. 05 with 29k miles.

 

a/t? M/t?

 

lol, Obviously a/t.

 

is it slipping? pull any codes? I'm guessing if you're feeling a shudder when it's at higher rpm's (b/w 3-4k) before it shifts to 4th.. I'd do a 3x3 and talk to a local tranny expert in your area who specializes in Honda & Acura transmissions. I Hate Car's talked to his tranny guy and he hypothesized that the 3rd gear & 4th gear pressure sensors going out of spec are causing transmission failures. If new pressure sensors / switches & a 3x3 don't do the trick then ask your local transmission expert how much to clean the valve body. You need to take care of this asap before further damage occurs.

Check out the thread if you haven't already:

https://acurazine.com/forums/showthread.php?p=10823650

 

It's got extended warranty. The car is a September 04 build, so it's the old design. They only switched to the new design in Feb 05. Wonder how long it'll last. Wierd that it only happens the first cold shift.

 

you only have 29k miles on a 4 yr old car.. unbelievable.. take it in and have them deal with it..

..and if they say they don't notice it.. have them park it at the lot and tell them you'll take the tech on a drive in the morning that way it's cold. They'll at least change out the ATF for you and verify if the shift solenoids and sensors are working. Take it in now before further damage may occur.