Jibb

My 2007 silverado classic is having a shifting problem. It seems to slip then grab between 1rst and 2nd at low throttle position, 25% to 50%. I noticed that it occurs if I increase the throttle position while the trans is shifting. It does not happen in tow mode or at full throttle. Wondering if anyone else has had this problem, or if anyone knows if this is a Ecm reprogram issue or if it is a internal issue.

Allan In NE

I'd stop by your dealer and see if there is a re-flash for that truck.

Allan

Jibb

Thanks Allan

Chevrolet Customer Service

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> Jibb,

I am sorry to hear about your transmission trouble. I have looked through my resources and am not showing any known transmission problems for 2007 Silverado's. If you PM me your VIN number, I can research your vehicle further. I may be able to find additional information.

Have you taken the vehicle in for an inspection yet? How often is this occurring? Is this a recent development?

I look forward to your reply.

Louis
GM Customer Service

Jibb

Hi Louis, I have not had a GM dealer look at it yet. I am trying to diagnose as much as I can before I bring it in. The problem doesn't occur all the time, but enough to be concerned. The vin# is 2GCEK13Z771154140. It seems like its a delay in shift at lower TP. I have learned to prevent this from happening by letting off during the shift. I take really good care of this truck. I have done two t-techs in 88k. I hope that its nothing serious.

Jibb

I did look up a CalID Part # for a GM reflash they listed two calibrations but no explaination.

Chevrolet Customer Service

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> jibb,

Thank you for providing your VIN number. After researching your vehicle, there are currently no open recalls, nor any information regarding the transmission currently available. I encourage you to take the vehicle in for an inspection. A certified technician will be able to offer a more accurate diagnosis with a physical inspection.

If you have any additional questions, please feel free to contact me.

Louis
GM Customer Service

Jibb

Thankyou Louis, I am making an appointment this morning. I will post what they find out.