Upon a full check on my uplander I found something that GM and all the owners should be aware .
#1 Inside the engine compartment the big bundle of wires inside the split loom that run in front of the engine near the strut stabiliser is rubbing againts the strut causing erosion to the loom. These looms are splitted to insert the wires and since there are tons of wires inside some wires are coming out of the loom. In mine 2 of the wires were almost cut because of the rubbing. Cure; I installed some rubber from inner tube tire wrapped around the loom and tied with tie wraps
#2 Under the frame near the driver the parking cable is rubbing in the frame as it curve to run to the back wheels. It is rubbing on sharp metal hole in the frame and on a long run will wear off the plastic on the outer cable. Cure; I installed a piece of braided hose that I cut open lenghtwise and inserted on that sharp hole edge opening.
#3 The other day while on the highway during a torrential downpour I lost the reading on my gas gauge. After the underneath was dried the gauge came back in operation. Since I was sure that this problem was caused by this rain I am sure that it was caused by the connector underneath the frame located around the rear seats that supply several fonctions of the vehicle. Even if this connector is supposed to be waterproof an located deep inside the frame it can get soaked quite bad in a heavy rain. Cure; I wrapped some inner tube around these bunch of connector going aprx 2 inches below and left it open under. Like this no more water will hit these connectors.
I will make a follow up with pictures this week on these 3 items that needs attention. By the way our uplander is a 2009.

 

Thanks for the update !!

 

Here are the three items pictures on the problems that can happens.

 

Excellent thread.... thanks for the alert.