07 Malibu AutoStick

[1fstfox]

My boss picked up an 07 Malibu maxx ss (3.9 v6 with autostick). Its got higher mileage (175k) and don't shift in the normal automatic mode. But if you put in manual mode it works flawlessly (other than having to shift manually). Anyone here familiar with these that could point me in a direction to possibly fix it? I was considering buying it off him for a cheap newer DD while I tear into my Sonoma but I don't want to have a rough idea what I'm getting into first. Thanks in advance fellas!

Sent from an undisclosed location using Tapatalk4

 

[Kaline]

The shifter itself could have a failure in the Automatic Transmission Shift Program Switch, which would cause it to be in Tap Up Tap Down all the time. Below is the circuit diagram for this vehicle TAP shift circuit. My suggestion is to pick up a used or new shifter and swap it in to see if this solves the problem. Best of luck!

 

[1fstfox]

Appreciate the response, looks like the flawless shifting in manual mode, isn't so flawless. Severe slipping in first, and semi severe in second. Looking a lot like a rebuild in its future

Sent from an undisclosed location using Tapatalk4

 

[Kaline]

In that case, it sounds like you have clutch slippage and potentially gummed up shift solenoids caused by old fluid. Before you totally rebuild it, change the trans fluid & filter. Drive it that was for a week or two to see if the fresh fluid will break down some of the internal deposits. I have saved a few slipping transmissions with this method, assuming the clutches were not too badly damaged. If this does not work, it most likely needs a rebuild.

Personally, I always change AT transmission fluid every 100k miles and MT trans fluid every 50k miles.