I have a 2000 Mazda B3000 Ford ranger with a 3.0 engine and auto transmission. I bought it about 3 months ago.

I recently "raced" a friend (and lost) and about the highest RPM I reached was maybe 4-5k, and I was flooring it. Before this I had not driven it crazy-like at all. I had replaced oil 1k miles ago, and was not low on oil either at the time of this.

I noticed on my way home that there is a slight but consistent rattle when above 1800 RPMs, it is worst at around 2200-2500 RPMS, and gets slightly quieter at any higher RPMs, but is still there. The noise is only there under acceleration or load, and mostly goes away at cruising speed. It seems to be coming from the engine. The noise is also not very loud at all, and you probably wouldn't even notice it unless you were the person who owns the car and listens to it every day. I have listened closely and I think it could be coming from the driver side, but I am not quite sure because of how quiet it is.

I have done a little research and some say it could be rocker arms, push rods, or hydraulic lifter adjusters. I am wondering if it is the rocker arms, if so how hard are they to replace, and also how important is it that I really replace them. The vehicle only has 131k on it.

The engine also ticks, but it did that before the "race" and I can hear a tick from both valve covers. The tick is a different sound from the rattle, and I am told that many fords do it. Is that serious or possibly related?

I have changed the oil and spark plugs (not wires yet), and the rattle is still there. It might be a tiny bit quieter but I am not sure. Would it hurt to just keep driving it and ignore the problem? How expensive could this be to replace? Could it be something else? Any information is appreciated. Thank you!

 

The "ticking" may be the fuel injectors, Ford injectors are quite loud, use a small hose like a stethoscope to see if its the injectors

"Rattle" could be pinging/knocking. 3.0l is know to do that, it runs 9.3:1 compression ratio, so can be Pingy on 87 Octane fuel if there are any other issues, i.e. vacuum leak or carbon build up

Try some higher octane fuel just to see if thats what you are hearing

3.0l Vulcan engine is a HIGH RPM engine by design
2000 3.0l gets best power(torque) at 3650RPM, most engines get best power at 2,500 RPMs
So 4/5k is nothing for this engine, best horse power is at 4,750
3.0l gets a bad rap for power because you need to wind it up above 3,200 RPM just to get going, thats the design, drive it that way


Fan belt noise
Rattle could be bad pulley
With engine Stone COLD, remove fan belt from crank pulley
Start the engine
Battery light will stay on
You can run the engine this way for only 2 minutes, no water pump
But with no fan noise in engine bay you should be able to ID a rattle
If no rattle then turn off the engine and start checking pulleys