There has been no bulletins posted in the last 2 weeks and nothing about the surge tank in 8 weeks.
The only surge tank cap bulletin has to do with the surge tank cap contacting the underside of the hoods of 1998-2002 Chevrolet and GMC C7500 Series Medium Duty Conventional Cab Trucks
I will check on Monday night, they may not have updated over the holidays.
I talked to General Motors, and they said there wasn't any bulletin. The dealer said that part #10296465-ACD#RC75, which is the original equipment, 15lb pressure cap has been replaced by an 18lb pressure cap, GM part # 25713160 ACD # RC87 (made in India). Cap is similar in design, except for pressure valve. They had no explanation, but you can't get the original one anymore, unless you find a dealer with old stock. My concern is going from the 15lb to the 18lb without any explanation. With the extra pressure build up, my concern is that it may crack the surge tank. I may be wrong. If anyone has any info on this, it would be appreciated.