Im having the same issue as yours.

I read somewhere that these things happen when the weather gets to be very cold.

Im not sure what my problem is. I cant hear the pump from the cabin. Ive only done the front bags.

I cleared the code the first time and it came back few days after. I cleared it again on I think friday so im waiting to see what happen.

Today I noticed one side of my reear was about 1/2 inch higher than the other. Lowered the truck and raised it back to normal and it was 1/4 inch off.

i dont know right now. all I know is im getting headaches from this truck that i got in june with 57k miles.

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2005 4.8is. Blue ext, white int.