I'm sorry if this is a repost, I searched and couldn't find what I was looking for. I've got a 98 F150 Lariat with 215k on it. Up until last week I've had no issues with it (still really no "issues"). Last week it started getting really cold here and I've noticed when I first start my truck I have no Oil Pressure, so says the gauge. I'm not seeing any temp differences or hearing any valves rattle or anything, and once the truck has warmed up a bit the oil pressure maintains just fine. Is this just due to the cold? When I do the next Oil Change I'm going to go ahead and get some High Mileage oil to put in and see what that does for me. Does this sound like it could be the oil pump? If so, where is it located? In the pan, or on the front of the motor? I only ask because I had a 91 Cougar with the dreaded 3.8L V6 and it's oil pump was mounted on the front and I wouldn't touch it. Something else the truck has been doing for about a year now, which may just be due to it's mileage, is that when it's first started up it sounds (really it does) like an 18 Wheeler does when it's going through it's first few gears. The motor does anyways. I know that may be kind of vague but it's the best way I know how to describe what I'm talking about. Any info would be appreciated.