Question about 2004 Buick LeSabre

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''04 Buick LaSabre, Transmission rough shifting. Are pressure control solenoid and shift solenoids internal to transmission?

This is a GM 4T65E transmission. I have been told that these solenoids most likely will cause rough shifting and are poorly designed by GM. Am hoping that they are external to the trans and can be serviced without a complete tear-down. Bill

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The solenoids are internal ! But if it were a solenoid problem the check engine light would come on . There are a lot of variables involved in the shifting of electroniclly controlled transmissions , it's all part of the engine management strategy programmed into the PCM - engine computer . I would take and have it checked before guessing about parts problems . A good qualified repair shop would hook up a professional grade diagnostic tool and road test the vehicle . With-in a few miles they would know for certain .

Posted on Dec 14, 2016


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Transmission sometimes shifts hard into next gear.

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