Rattling sound under hood when getting up to 55+ MPH?

Question

I have a 1997 Ford Explorer and I noticed that when I get up to speeds like 55mph and more there is a very loud rattling sound coming from under the hood. Is this a sign of a bad rod? Also when I am turning or backing up there is a creaking noise (almost like popping popcord but on slow) coming from under the truck.

I am more concerned about the rattling also. If anyone who is a Mechanic kind of knows what this could be?

Ok I just drove again to go to the store. At low speeds you can hear the rattling but it seems to come and go. The highest speed I could get up to was about 60 MPH then it would not go any faster no matter how hard I tried. When trying it feel like I was losing accleration.

The creaking (popping noise) is a different thing.
I am more concerned with the other issue.

Answer 1

If you are getting a popping noise when you turn I'd say it's a ball joint that's bad.

Answer 2

When you say this happens at 55+ highway speeds, I don't think you'd be turning sharp corners and hearing a CV joint noise. But, certainly, at slower speeds that could be it.

Does the noise get louder going up a hill or when the engine is otherwise under a heaver load? If so, that sounds like an engine ping which might be cured by simply changing brands or more than likely, grades of gasoline. Try running the tank nearly empty and then putting in the higest test gasoline you can get and see if that helps.

This could also be something called piston slap. It'll kind of sound like a sewing machine when you step on the gas. There's nothing you can do about that, short of a major overhail.

When I was a kid, we had a Ford that the tappets made a sewing machine type noise and it ran years.

Cars can make many different types of noises that originate from many, many different sources and problems. I hope your problem is engine knock that can be cured with changing brands of gas or an anti-knock gas additive.

Answer 3

Let's take a stab at the loud rattle at hwy speeds.

#1. Possibly the cooling fan or radiator fan which is mounted to a "clutch" that makes it spin faster when hot. This clutch can wear out and the fan will wobble and might hit a belt or pulley while running. Engine can over heat, too. Need to look at the alternator and water pump and smog (air) pump too to make sure they do not have a bearing going bad in them. A bad "rod" will crash very loudly even when accelerating around town from a stop or low speeds.

#2. The other creaking noise might be one of the outter constant velocity joints (CVJ) on the front end (axles) or maybe a U-joint on the driveshaft.

All of these noises could be from a worn u-joint or CVJ on the driveshaft(s) but they sound separate the way you described them.

Fix-Or-Repair-Daily (FORD)

Good Luck!

Answer 4

if your serpentine belt has ninety 5,000 miles on it it fairly is late for replace. yet your serpentine belt would not make a damn sound. A damn sound is frequently led to by using a loose ingredient. initiate by using commencing up the hood previously commencing the engine, and attempt to go or shake factors fastened to the engine. the only areas that would desire to pass are rubber areas like hoses and belts. If something else shakes or strikes, see if it fairly is tightened, repositioned or replaced. the subsequent step is to seek for a factor that has a shiney spot the place it fairly is been rubbing up against yet another area. this may well be the source of the rattle. Reposition, relocate,tighten or insulate the area (wrap with electric powered tape). If each little thing seens tight, get out a wrench set and verify that each seen bolt is comfortable. in case you come across no areas exhibiting the above alerts, it's time to start the engine. right here, you pick to look and pay attention yet don"t touch any shifting areas. Unfortunatley, this technique would not continuously hit upon the rattle, in spite of the fact that if it fairly is a sturdy place to start. And once you talk with the mechanic after that, you would be somewhat accustomed to how your automobile is prepare, and could no longer sound naive.