Very Hard 1-2 shift, Service Stabilitrak Light

[Al Torrez]

Long time reader, 1st time posting..

Here we are 2 years later... hoping we found a solution... 2008 Yukon Denali 188k.

Symptoms
-"Service stabilitrak" "Traction control off" etc has started popping up.
- Lets me run in what i think is 2nd or 3rd gear only.
- Loud clicking in dash (can't pin point)
- CEL comes on
- Gauges go crazy (according to the clicking)
- I shut off motor and 1- Wont start (wont recognize that is in in park, have to put in Neutral) OR 2- Starts but all previous symptoms resume.

Short term solution
- I Disconnect both poles on battery. Wait about an hour and connect both poles. Starts like nothing ever happens. Runs PERFECTLY SMOOTH for about a month then it happens again.

What I have done so far
- New Battery
- Tranny serviced.
- New plugs and wires.

I just want to be clear... when the service lights are not on, the vehicle runs like new! One mechanic told me i need a new transmission. Unacceptable.

Next step is the Stealership... which I really don't want to do.

 

[bnjalal]

Hope Im not spamming, and to be honest I didn't read except the first few posts on the first page, and the last two. Anyway, may I suggest that you check your brake light switch ? ( sorry if this was mentioned before ) I'm having similar issues and over here (somewhere in the middle east)

I noticed getting those lights and chimes at random times when holding the brake pedal constantly for some time like at a red light stop, then it started getting worse, turning the vehicle off and on fixed it until a few stops, disconnecting battery didn't help
(hard or rough transmission shifts included) until I noticed that when I press the brake pedal the red lights won't light up and rarely, I cant shift out of park until I tap the brakes a few times

So I kinda know whats the issue ( cheap chinese obd scanner just shows tps error and went away after cleaning throttle body which is also related somehow )

Hope that this helps someone and save a few bucks or please accept my apologies if this was mentioned before

 

[bnjalal]

Hope Im not spamming, and to be honest I didn't read except the first few posts on the first page, and the last two. Anyway, may I suggest that you check your brake light switch ? ( sorry if this was mentioned before ) I'm having similar issues and over here (somewhere in the middle east)

I noticed getting those lights and chimes at random times when holding the brake pedal constantly for some time like at a red light stop, then it started getting worse, turning the vehicle off and on fixed it until a few stops, disconnecting battery didn't help
(hard or rough transmission shifts included) until I noticed that when I press the brake pedal the red lights won't light up and rarely, I cant shift out of park until I tap the brakes a few times

So I kinda know whats the issue ( cheap chinese obd scanner just shows tps error and went away after cleaning throttle body which is also related somehow )

Hope that this helps someone and save a few bucks or please accept my apologies if this was mentioned before

Ok, so I replaced that brake light switch at the pedal and things went back to normal again, transmission shifts better now but the oil is burnt, gonna flush it and drop the pan for a new filter and hope it can survive another year or two, good luck everybody !

 

[ronnyballgame]

I have the same thing going on. Replaced the brake light switch but no change. Too cold to clean the throttle body myself. Going into shop Monday

 

[benj]

FYI, I just had this happen to my 2007 Tahoe: stabilitrak warning (random/intermittent), power issues, check engine light, hard shifting from 1-2nd gear. Took it in and had the spark plugs replaced and it runs like new. Seems this is tied to lots of things but wanted to share my experience--hopefully it's relatively inexpensive fix for you guys that like to fix your own and the ones like me that don't have that technical knack.

 

[Yoandy]

[QUOTE = "Brougham, post: 230266, member: 3924"] Mi 07 Yukon desarrolló recientemente un problema interesante, mostrará aleatoriamente un mensaje de advertencia de "Service Stabilitrak", "Control de tracción desactivado" o "Service Stabilitrak". Si bien se muestra esta advertencia y solo mientras se muestra, cambiará muy fuerte de 1ra a 2da marcha, el cambio es lo suficientemente difícil como para que si estoy acelerando con fuerza mientras hago esto, en realidad hace chirriar los neumáticos. (Ahora he estado evitando la aceleración brusca).

Estoy tratando de averiguar si esto es un problema dentro del sistema TC / Stabilitrak que hace que la transmisión cambie bruscamente, o un problema de transmisión que hace que aparezcan los mensajes de advertencia.

¿Alguien se ha encontrado con esto antes?

I had a local transmission shop that I've used for years, look at it quickly and they're stumped, no errors from the control modules other then that the Stabilitrak was disabled.

I'm going to start by checking all my wheel sensor wiring this weekend, if I don't find something obvious I guess I will have take it back into the shop for them to tear into.

Any suggestions as to what would cause this? Perhaps problem areas I should look into?

(I've searched the forum and could not come up with anything specific, just different trans problems causing a similar error message on an older model)[/QUOTE]

 

[duworm]

I am glad I found this thread. My 2007 Yukon with 148000 miles problem started with a instant really hard 1 to 2 shift, all the stable drive dummy lights came on along with the check engine light. Engine started running rough, hard steering, and the problem would come and go. I had all of the issues discussed in the thread above. A crap load of codes (over 40) showed up and every transmission sensor was showing failed. Interesting, not all of the codes were transmission related. They included misfire on all cylinders, O2 sensor failure, throttle body position failure Shaft position sensor failure and several others. There was no sign of a cascading failure or any common issue among all the codes. Above all, it was the really hard shifting that bothered me the most. Made me think I might need a new transmission. I read about old or bad trans fluid discussed several times above. My first thought was how silly. But before I started replacing all the sensors and checking for the multitude of transmission electrical wiring that might be faulty, I gave it a try. It worked. Holly cow did it work. All the transmission problems went away, engine ran smoother, shifting was smoother than before. I cleared all the codes and drove for 50 miles. I have not had any codes since. Even my wife noticed how much smoother the engine ran.

Thanks again to the guy that posted that changing the trans fluid worked for him.