2002 4.7L 5 speed 4x4 120,000 miles Mobil1 oil and filter. Sometimes when it is very cold (15F or less), i hear a terrible grinding noise on startup. Grinding or rattling, hard to tell, but its pretty loud. The noise only lasts about half a second, the engine seems to run pretty good but milage is low about 14.5 mpg.

Sounds like noise is coming from the top of the engine. Maybe the lifters? Should i be worried? I am not a mechanic, so I would love some advice. You guys are amazing on this forum, I read it quite often just for fun.

I heard the noise first a couple years ago. Last year wasnt very cold in PA so it didnt happen at all. But now we have cold temps again and I heard the noise again. For now I will try to avoid driving my truck on these crzy cold days. Thanks for any help.

 

Oh stop the flattery ☺️, you're too kind.

I can try to help, but I'm an amateur and these guys helped train me in a sense. How well do you get your oil levels? Perfect? Because to be honest, the only thing I can think of is what retired my original engine 4k miles ago. But it shouldn't have happened to such a low mileage engine. I'd ask for a sound or video clip to help give me a definite answer.

 

how long does it take for oil pressure to build after start? The needle should jump up within a second. Any correspondence to the sound? Check the starter, it may have come loose when everything contracted from the cold, or may have come loose period. Or it may be hanging up on the flywheel.

 

The oil pressure with the 4.7 should be past halfway upon start. Mine shoots up while I'm cranking.

 

Post up a video so we can hear it. Normally in the first few seconds, you'll hear some clatter, right before the oil circulates. Shouldn't be terrible as you describe though. I'd be using the lightest weight synthetic recommended, if I were you.

 

Thanks for all the suggestions, I think it is the starter like magnethead said and my Dad agrees also. I need to check to make sure it's tight, then I will take it off and clean it if it's possible.

I got a video, but it only made the noise a little bit, you have to listen carefully because it happens so fast. There is 2 clips recorded at the same time from 2 different smartphones. The volumes are different so you have to turn up the volume for the second clip, sorry about that. It's only a very short grinding sound right as the engine starts.

http://www.youtube.com/watch?v=OxHtb...ature=youtu.be

Theres another sound you can hear when the engine is running. I think its bad bearings in one of the pulleys or something that's related to the belt. I will have to look into that too, the video makes it sound worse than it does in real life.

 

HI I have a 2011 Dodge Dakota with the 3.7l V6 and I'm having a similar problem. Not so much as its cold outside but once the engine has been sitting for 4-5 hours and is completely cooled down, every once and awhile upon startup I hear a grinding/rattling/squeaking sound just before the motor turns over. Not sure if it's related to your issue. Any advice?

 

Derek, your question belongs in the 3rd gen Dakota section.
We don't have the 3.7l in any of our trucks.

Also, I realize this thread is like 6 years old, but just encase some random internet persons stumbles across this, I'd like to add I've had 2 high mileage 4.7l Dakota's and 1 high mileage 4.7l Durango and they all make clatter noise when cold. The Durango also makes the short noise in the video sometimes when the engine first starts. I have zero intention of trying to figure it out.

​​​​​