2003 Tahoe 5.3 Flex:

Trying to R/R the idler pulley located next to the alternator, not to be confused with the tensioner pulley which is situated at the extreme passenger side of the engine.

Advance Auto advertisers PN # 89006 : "direct fit, reuse the OE bolt and washer." Sounds great.

My experience : the idler pulley that I removed had an exterior dust shield style large washer that is cup-shaped.
The original idler pulley PN # GM12555609 had a recess to accommodate the cup-shaped washer.
The new Advance Auto PN # 89006 does not have the recess , hence the dust shield washer will not fit.

I called Advance Auto 800 phone for guidance/ information. Result = no help.
I was referred to my local store Advance counter professionals. Result = no help, not know anything. They repeated : " direct fit".

Does anyone know why the parts do not match?
I am inclined to leave off the outer dust shield washer and install the new PN # 89006 from Advance Auto.
Guidance appreciated.

 

Go back to the store and see if you can match to one of their other brands of pulleys. They have several manufacturers and one of them might be a better fit. You can also press out the old bearing in your old pulley and replace the bearing and reuse the old pulley.

 

Leave the dust cap off or get a direct fit AC Delco/GM part and stay away from aftermarket crap.

https://www.rockauto.com/en/moreinfo...12244&jsn=1053

 

Gentlemen, thank you.
Installed w/o dust cap because it was already disassembled.
The RA part that you suggested looks exactly like the one that I removed.