labradort

I just bought a used 1998 Nissan Frontier 4x2 with 4 cylinder engine.
It is in pretty good condition but it was used for commuting and
has about 143,000 miles on it.

I previously owned a 1995 Toyota Tacoma and I have to say that
the Frontier beats it for ride comfort and seat comfort. The only
aspect that was a little nicer in the Toyota was the steering (rack
and pinion and double wishbone), but this isn't a big bonus on a truck.
The Frontier has 15" rims and other little things the Toyota doesn't.
Where the Frontier has a engine that makes a gyroscopic sound, the
Tacoma has very noisy solenoids on the fuel injectors. My wife now
confesses it drove her crazy.

I say these comments because on sites where these things
are rated by owners, I see a number of Nissan owners who
say that they wished they had a few more bucks
and bought a Tacoma. Well I've been on both sides of the fence and
I can tell you the grass isn't greener, it is just a little different.

I've been reading some things here and on the Internet
about possible sources of an unusual drivetrain related noise
on my Frontier. It sounds like a mild buzz/whirl/hiss and it
only kicks in at 2200 RPM, in any gear. This sound is heard
regardless of the engine or outside temperature.

I've seen people talking about timing chains, guides, pulleys, and so on,
but quite a few of them are regarding the older Nissan trucks
(Hardbody - pre 1998). Mine is a Frontier and so I don't know
if those bits of information may not apply.

I've already switched to Mobil 1 synthetic 10W30 and it sounds
exactly the same (wanted to do it regardless of the sound issue).

I'm taking it to my mechanic to have a look over on Monday (March 1st).

Does anyone have some hints on what to check on a high mileage
Frontier 4 cylinder engine or other parts that could be the issue?