i have an 05 LE 4x4. The other day i noticed the oil pressure gauge acting up. When I crank it up and it revs normally as it does and then idles high during cold start, the oil pressure gauge pegs out to high and stays until it warms up and idles down. Also even when it is at normal running temp. it seems to peg out under any acceleration and stays pegged until it goes down very near idle. truck has 40k miles on it and no other problems....whadaya think the problem is?