Yes, the oil pressure is constant and the noise isn't constant.

If it was a main bearing how much would that cost me?

Mainly I'm most concerned with problem 1 - could this be a transmission problem or something related to a spark plug or serpentine belt? I do know I should be replacing my serp belt soon and I haven't checked my spark plugs since I got the car. Anyway, I'd appreciate some help here.

dead on the money man that is your soon to be pain in the ***

your transmission will go soon

here is a question to you how many miles is on your car

wakefieldl (lucas)....from what I have read so far, we don't know that his transmission has ANY problems at this point. Please be cautious about making these kinds of statements without providing why you think this will happen.

Please share your reasoning or background information on why you think his transmission is failing?

The engine has about 30,000 miles however the car has around 120,000 miles on it. I hope it'* not a transmission problem... I thought transmission problems were most often diagnosed by difficulty in shifting or grinding when changing gears, both of which I don't have. :?

That is exactly why I wanted to point out that nothing here points to ANY transmission problems. I am assuming he was just eager to help.

My first educated guess would be that at some point the engine you have had an upper intake manifold failure and the oil wasn't drained immediately, causing the rod bearings to rust and fail.