Alright I have a 4T40E Transmission with close to 39,000 miles on it. When under hard acceleration (3/5 to 3/4 to the floor) In between 1st and 2nd gear it revs up and shifts hard into second... I don't think this is normal, but what can i do to fix it? How much on average does it cause to rebuild one? Thanks!
is the car going or is it just revving????? if it is going and shifting hard like that. check your iat sensor. mine was doing the same thing after i put my intake on and all i did was plug my iat sensor back in and it hasnt done anything else. but if it is just revving you probably have a slipping problem..call around to your local tranny shops and see how much they would charge to rebuild one.
how do you drive your car .. do you beat on it ... or do you just give it TLC??
dan
I guess you'd never want to use the AutoTransInterceptor then. lol
Don't worry about it.
The 4t40e is a solid tranny and can't be broke. Well, under most conditionss.
I've got 145,000 miles on the odometer and tranny with the Autotrans unit on the car for over 2 years with no problems. The Interceptor has been set at 75 percent line pressure and all the way up on the other setting with no problem.
It shifts hard but love it that way.
For the stock tranny, shifts like a little girl. lol
Keep the fluid in good shape and topped off and you should have no problem with the 4t40e.
misnblu
Misnblu.com
Newbie member since 1999
Thank you Dave and JBO! 
I think it was the tranny fluid, because it only acts up when its rather cold out in the morning... I don't beat on it unless I have to (Someone won't let me over on the interstate etc etc.)
Quote:
I think it was the tranny fluid, because it only acts up when its rather cold out in the morning
that is that perfect time to be gentle on it. Very gentle ... do you start playing football when/if you dont warm up??
dan
Representing the 810's ... biatch!!
Wow... nether thought of it like that... Thanks, yeah im going to swap out the oil in it then baby it for like the next 2 years
I know mine, for a stock auto, has a really hard shift into second under 3/4 to full throttle. I dunno why, but I ain't complaining
when i got my car stock, the auto trans could chirp 1-2. Now i got the supercharger and i get something weird, like if im doing about 25 MPH or so and in a high gear 3rd or 4th, if i punch on the gas it downshifts, then when it goes to shift to second it does like a double shift. Really loud and i feel the trans shift like two times really quickly it shakes the car. Needles to say im very careful when i punch it, but sometimes i forget, anyone else have something like this?
2006 Black Cobalt SS Supercharged G85
13.91@102.77
I'll let you know when I find money for a supercharger
Yeah... Mine Slams it in second, without the auto trans on it still chirps second... Im not complaining im just worried some times when it seems like its slipping.
-JaysonZ24- wrote:when i got my car stock, the auto trans could chirp 1-2. Now i got the supercharger and i get something weird, like if im doing about 25 MPH or so and in a high gear 3rd or 4th, if i punch on the gas it downshifts, then when it goes to shift to second it does like a double shift. Really loud and i feel the trans shift like two times really quickly it shakes the car. Needles to say im very careful when i punch it, but sometimes i forget, anyone else have something like this?
I wonder if the new program did that. Maybe to safeguard the tranny or something?
-JaysonZ24- wrote:when i got my car stock, the auto trans could chirp 1-2. Now i got the supercharger and i get something weird, like if im doing about 25 MPH or so and in a high gear 3rd or 4th, if i punch on the gas it downshifts, then when it goes to shift to second it does like a double shift. Really loud and i feel the trans shift like two times really quickly it shakes the car. Needles to say im very careful when i punch it, but sometimes i forget, anyone else have something like this?
Hmmm, I've actually felt the same thing but my car is N/A. Ive been having this "shifting problem" since about 40,000 miles. Of course GM techs couldnt tell me WTF was wrong. They said it was normal. "No codes stored, must be ok".......damn GM. So what I usually do is take off the negative(-) off the battery for about 5 hours or so then once everything is put back to normal, Waalaaa! Shifts like the day I bought it, nice and smooth! But after about a day or so, hard shifting from 1-2 where you literally feel the car "shake" through the damn steering wheel. I also feel that "double shift" but only in the 1-2 shift as well. At first I thought that it was the ignition, so I got new plugs and new coils but after a couple of days, it starts to freak out! I dont beat the crap out of my tranny and I normally drive like an old man. I keep up on the maintenance of the tranny and motor.
I hate this hard shifting already and no one knows WTF is goin' on!!!!! My moms Old's does the "double shift" as well. I wonder if it only exist with GM cars only.........???
H.O.N.D.A = Hold On Not Done Accelerating
