Isuzu is asking $1800 out the door for all 4 boots changed up front. They said they were torn, has dirt in them and even melted onto the throttle cable. Haven't seen it yet to confirm. Is actually in there for high and fluctuating idle and the previous owner put tranny fluid in the brake cylinder so all the gaskets and seals swelled up and is hard to stop. Local shop down the street quoted $160/boot.