Very Hard 1-2 shift, Service Stabilitrak Light

[jstutz101]

Not sure if this helps but I have a 2007 Siverado 2wd that had a similar problem with the "Traction Active" turning on when accelating from a dead stop. Long story short the trouble was a front wheel hub assembly. When the sensor goes bad the truck thinks it's stuck and engages the traction control.

The bearing was fine but the sensor was bad. For some reason replacing just the sensor won't fix the problem (tried that). The good news for do-it- yourselfers is its not to hard to replace the hub.

Good Luck!!!

 

[minkwonee]

I'm all fixed up!.... finally

I realize this won't apply to everyone, but here's my story:

It turns out my stabilitrak light was coming on due to a "lean" signal. The signal triggered codes for my throttle body sensor and mass air flow sensor. I went ahead and replaced both of those, but no improvement. It's sad, but the problem was my K&N air filter was dirty.... that's all. Had it cleaned and the signal went away, and it has been running smoothly since.

As for the high revving and bad shift between 1-2, I realized it mostly happened on uphill slopes, and on right turns. Later found out that my left motor mount was completely shot. I went ahead and replaced both motor mounts, and now that problem has also gone away.

Hope this helps some of you.

 

[lowexpo]

Well cranked truck for first time in a couple of days and it would barely run. Idling below 500 with surging. Id remembered reading Ben's post, that Ben guy is pretty smart for an Auburn fan hahaha. Checked my intake connection at throttle body and the grommet had a small gap where the tube had came loose. Tube still looked attached. Reattached tube and cranked truck and idles fine with no indicator messages. Drove to store and it drove normal. Guess ill see on the drive home but pretty sure it's fixed. I'll repost when I home.

 

[nukstr]

Fixed "service stabilitrak & traction control", "hard shift 1-2", "stabilitrak off,

FINALLY FIXED, "SERVICE STABILITRAK & TRACTION CONTROL"
DIAGNOSTIC PROBLEM:
"SERVICE STABILITRAK",
"SERVICE TRACTION CONTROL",
"HARD SHIFT 1-2 GEARS"-(STABILITRAK TURNING OFF-CLUNK NOISE)
"STABILITRAK OFF",
"TRACTION CONTROL OFF"
----------------------------------------------------------------------------------
CAUSE:
FUEL WAS 45% ETHANOL @ 85-(COSTCO GAS)-COMPUTER WENT INTO LIMP MODE CAUSING (AFM) TO GET STUCK AND NOT RESET COMPUTER.
----------------------------------------------------------------------------------
SOLUTION:
DRAINED & CLEANED GAS TANK-
CHANGED FUEL FILTERS (*ONLY IF NEEDED)
CLEANED INJECTORS-
RESET COMPUTER-
FILLED GAS TANK WITH NO ETHANOL- (http://pure-gas.org/index.jsp)
TOTAL AMOUNT WITH TAX: $444.86
----------------------------------------------------------------------------------
REFERENCES
(STABILITRAK CLUNK NOISE): http://chevroletforum.com/forum/sil...21/2010-silverado-stabilitrak-question-47580/
(AFM)-Definition: http://en.wikipedia.org/wiki/Active_Fuel_Management
(ETHANOL): http://en.wikipedia.org/wiki/Common_ethanol_fuel_mixtures
(GAS STATIONS WITHOUT ETHANOL): http://pure-gas.org/index.jsp

 

[tundrayetti]

I wanted to post the solution to my issue. The more solutions everyone has, the better off everyone will be when diagnosing their issue. However, let me also say that there CAN be multiple solutions to the same problem(s). So this may or may not be YOUR problem.

I was experiencing the following with my 2007 Tahoe two weeks ago:
Stabilitrak OFF light on
Service Stabilitrak notification
Service Traction Control notification
Check Engine light on
Hard shift from 1st to 2nd gear

Long story short, I'm a decent mechanic, but I'm in the Coast Guard and am currently deployed in Afghanistan. This happened while I was home on my two-week vacation, and I didn't have time to fool with it. So I decided to take it to the dealer.

NOTE: ALWAYS request your old parts when having a mechanic work on your vehicle. SOME of these places, as you may know, will take advantage of you.

My problem ended up being a bad exhaust lifter on the #1 cylinder. The spring had seized and was not operating properly. See the picture, and notice the one lifter that doesn't look like the others.

Don't fool yourself. A problem like this CAN cause ALL of the symptoms I listed above. Vehicles these days are ALL electronic and everything is computer based. When one problem occurs, it can cause a plethora of other problems.

Lifter replacement is not a basic endeavor. The cylinder head has to be removed for starters.

It's not cheap either. It cost me $2,150. However, the good news is, my vehicle was repaired in 48 hours and was back to being a dependable vehicle for my family, prior to my return to Afghanistan. Sometimes a peace of mind is worth the cost.

Good luck

 

[Keanen55]

I think my 2007 Yukon XL has now beat the record for any car I have owned for the amount of problems and service we have had to perform: an oil consumption issue that according to GM is normal (1.5 quarts every 3k miles), bad wheels sensors, remote start problem, alternator, a window switch and finally- an issue that began about a year ago that seems to be occurring more frequently lately.

The transmission shift lever on the column will sometimes lock, not allowing to move from PARK, as if I don't have my foot on the brake petal, despite having my foot on it. Then, after lifting my foot off the petal and back down again it, and wiggling the lever a bit, it will allow me to shift. Simultaneously the "service stabilitrac" and "service traction control" warning lights appear until I turn the car off again and it sits for 5 minutes. The first time it happened it went many months without issue, then it happened 3-4 more times about 3 months ago. Until recently I had just assumed it was due to me shifting the vehicle into drive too quickly after starting the vehicle. Within the past two weeks however it has happened 10-12 times, including three times today. I am now concerned since each time this happens the lever remains locked and we cannot put the car into drive.

I'm having the exact same issues with my 2010 now. I'm getting frustrated because my 2007 Denali was full of gremlins like this as well!!

 

[Clean07Burb]

My "Service Traction Control/Service Stabili-Trac" light just came on along with a hard 1-2 shift while coming down my driveway. I was able to get it to go off by pushing and holding the traction control button for about ten seconds. It then came back on about two minutes later along with a random hard 1-2 shift. Just ddisconnected the battery about 30 minutes ago in an attempt to reset everything. I'm going out to reinstall the negative terminal and see if the problem returns immediately, over the next day or two, or not at all. I'm hoping for the latter! I'm wondering if something got wet that shouldn't have, as this occurred on my way home, about 10 minutes after a thorough car wash.

 

[wjs03]

Same issue here.
2007 Yukon XL
Intermittent "Service Traction Control/Service Stabili-Trac" light with a hard shift from 1st to 2nd. Everything goes back to normal after 2nd gear. Mostly happens at idle.

 

[Keanen55]

Happened to both of my Tahoe's. Both times was a bad speed sensor. Good luck.

 

[Goodinblack]

So this light comes on for any myriad of problems????