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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), GMC Mechanic
Category: GM
Satisfied Customers: 29396
Experience:  GM Grand Master Technician 2007. 14 years experience.
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2003 GMC Envoy: automatic doesnt..shift gears

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I have a 2003 GMC Envoy with automatic transmission and it appears to be having problems. I was told last year that I needed to have the transmission rebuilt.

Frequently when I drive my car it sounds as if there is a giant turbine fan under the hood and the car doesn't want to shift gears. It does eventually, but it sounds terrible. I can compare the noise to a "giant turbine fan" but some say it sounds like the engine is racing. Not to me, it sounds like a giant

Does this make any sense? Any suggestions?
Welcome. Is the check engine light on?
Customer: replied 7 years ago.

on and off. It comes on periodically, then goes off. It hasn't come on and stayed on for any length of time, i.e. weeks. Just a day or two then it goes off. It doesn't always coincide with the noise either. Sometimes the light comes on and I don't have any trouble whatsoever with the transmission, then other days it does seem connected.


Not much help, sorry...

Ok, These fan clutches are known for issues and often when they fail, they stay engaged making the Whooshing noise you have. The repair is to replace the fan clutch.
Customer: replied 7 years ago.
The fan clutch was replaced last year when I first started having this noise issue. After it was replaced I still had the "whooshing" sound and the mechanic said I need transmission work/rebuilt. Does a fan clutch just last a year, typically?
No, often once is enough. Can you check the level, colour and smell of the transmission fluid?
Customer: replied 7 years ago.
I had that done 2 weeks ago and was told all was okay. Fluid level was good, color and smell were normal.
Ok. What is the code that is set?
Customer: replied 7 years ago.
? I don't know what you mean. I haven't taken it anywhere yet for it to be worked on again. Are you talking about the service engine soon light? If yes, then I don't know what the code is because I haven't taken it to be checked yet. That was not done when the fluid was checked 2 wks ago.
Yes I mean the service engine light. You will need to get the code. If the light is on now, most part stores will scan for free.
Customer: replied 7 years ago.

so, do I go get the code then get back to you? or is this all you can do and I have to start over?


Thank you.

Get the code and reply back to this post.
Customer: replied 7 years ago.
There was only one code - P1481
OK, This is tied in with the fan. It is likely that you bad wiring, controller or even a bad fan clutch. I think this issue will require hands on diagnosis.
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