2003 GMC envoy humming - Cars & Trucks

Question edited for clarity.
Question moved to model category.

Click on the images tab. You can also search for a service manual.

https://www.google.com/search?q=2003+envoy+transmission+wiring+diagram

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That is always a problem with Mix and Match. Check wiring

2003 GMC Envoy Radio Wire Guide

MODIFIEDLIFE https://www.modifiedlife.com > 2003-gmc-envoy-radi...
Our 2003 GMC Envoy radio wiring diagram shows you all the radio wire colors and what they do. Table of Contents. 2003 GMC Envoy Radio Wiring Diagram; 2003 GMC ...

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Same problem on my 04 Silverado, then it stopped ejecting them. I had to replace the stereo.

https://www.google.com/search?q=cig+lighter+fuse+panel+on+92+gmc+half+ton&biw=1361&bih=650&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwj_--aUpbvQAhUE4yYKHTvTBg4QsAQIKw#tbm=isch&q=How+do+I+locate+the+reverse+input+wire+on+my+2003+GMC+envoy

Hope this helps

There is a linkage hooked to the indicator that may be broken

the last cylinder is the number 6 front to rear

could be a front hub bearing going bad have heard that before

Usually this is a sign that you need an alignment. Do previous front tires show any wear on the corners? My guess is that the noise returned when the new front tires "broke in".

about 5 litres

You need to replace the two gas struts on either side of the rear hatch.