I have a 2009 Chevy Silverado Hybrid 2 mode. I have almost 190,000 miles on it and other than replacing the front wheel bearings (a common issue). I've not had any problems with the hybrid part, until now. I saw the check engine light came on. The truck seemed to not want to go when I am stopped and then engine was on standby. It wouldn't do anything for a few seconds, then the engine would start and then it would go. The truck would also seem to want to go into electric mode when slowing or stopping, making the truck not stop as quickly, which was a little scary. I brought the truck down to the dealer. They did a checked it out and gave me an estimate of almost $5,000. The diagnosis included: A cracked exhaust manifold (don't know why as the truck is silent with no exhaust noise whatsoever), they explained that the cracked exhaust fouled and clogged the catalytic converter (Again, the truck showed no loss in power of fuel mileage, which is typical of a clogged converter). They also mentioned an auxiliary pump needed replacing (now that makes sense). The mechanic then went on the explain that once the check engine light is on, it won't go into hybrid mode, so I needed to make those repairs for it to work again. Again, this didn't make sense to me as the check engine light was on once before for something else and the truck still ran fine in Hybrid mode. So I took the truck back and a guy I work with is friends with a mechanic that works on Hybrids . He called me and said the auxiliary pump was low on fluid, but there was a bad wire in the wiring harness for the module. He charged me $130, and the truck has been fine ever since. So beware of taking the truck to the dealer. They were trying to steer me into purchasing a new truck, but I love this truck and served me very well and I will drive it until it dies. I have been very loyal to Chevy , but I am seriously disappointed in their dealer repair shops