I had this same problem so I opened the hood and come to find out there was migit materbating under it
Bad belt tensioner idler wheel, and serpentine belt.
sounds like the cv joints need replaced
I'd like to know too! Mine does the same thing - it makes a rattling noise upon startup that goes away after 30 seconds or so and isn't present while driving or idling.
Perhaps upper strut mount?
Yes. I have a 2002 Chevy Silverado that was making a rattling/pinging noise. Sounds like somethings loose, like thin metal rattling. Took to dealer, they replaced both oxygen sensors pre-catylitic converter. Sound was gone and acceleration was much better. Did not notice how sluggish the truck was until these were replaced. The noise was very annoying too. The truck was only about 2 or 3 years old when the noise started. Now my truck is about 9 years old and the sound is back. So I will be replacing them again soon.
When they don't feel like making noise and at night.
sounds like your valves are rattling check your oil
SQUEEEEEEeeeeeee! WAWK WAWK WAWK! also, they make a little rattling noise with their beak sometimes
Try to locate the rattling noise. I would especially check the catalytic converters if the noise sounds like it is coming from underneath the vehicle. Usually throughout some time the honeycomb material inside them will break up from 'heat stress' and will rattle around there. In some cases it can get lodged int he pipe between the converter and the muffler blocking some of the path of the exhaust causing some major performance issues.
The rattling and whistling on the 94 Explorer sounds like an exhaust problem. Check the exhaust for any leaks or loose connections.
It might not be the gearbox. Does it sound like it's coming from below the gear lever? I had the same problem in mine, and it turned out to be the exhaust, which was loose and rattling. It was fixed by putting a hard rubber spacer between the pipe and the car.
A possibility may be a loose catalytic converter shield, or loose muffler hanger or clamp. Usually a noise like this is caused by something that is loose and vibrating. These issues are usually not complicated or expensive to fix. If you're talking about the engine making rattling noises, the timing may be off, or it may be running too hot. Also, make sure you're using gas with the proper octane for your car. An engine noise like this is called "detonation". Detonation can cause engine damage if left untreated long enough.