No they are not required to fix a TSB, only a recall. I had a similar issue with a Dodge Ram there was a TSB for the engine manifold pan gasket, but i would have had to pay the dealer to do it so I just went to my regular mechanic.
The TSB is only a service bulletin to point the tech in the right direction when troubleshooting. I don't agree that we should have to pay for a manufacturing defect/design flaw, but that's how it goes.
'06 Crew Silverado 4.8L 3.73 4WD G80 Granite Blue Metallic
'08 EC 3.7 Auto 3.73 4WD G80 Granite Black Metallic - Traded for 2006 Silvy
If your leak is coming from the cowl area, you can follow the directions in the TSB and fix it yourself. You would remove the wiper arms and plastic cowl cover to get access. Other than a few dollars for a tube of silicone, it's a cheap fix.
"Brownstone Bumblebee" 2016 Diesel Colorado Z71 CCSB 4X4, Brownstone Metallic
HPD and Provent 200 Catch Cans, Amsoil Fluids, MetalMan Front Differential, Engine Oil Pan, & Steering Motor Skid Plate, Undercover Swing Cases
Say No! to Wheelers's Offroad!
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