3.4l 2004 engine clanking

Hey guys,
I'm new here and need some advice!

I took out my Tacoma 3.4 (135k miles) on some trails the other day, went around a bend and hit a dip going maybe 15mph, noticed a loud tearing sound but everything seemed to be fine afterwards. I don't beat it or overheat it. Went driving around for another hour or so. Heading out of the woods, I was accelerating on the highway and all of a sudden a loud clanking sound is coming from what seems like the engine. Stopped truck to look,clanking is happening while Idling and gets faster and louder with acceleration. Almost sounds like metal on metal,which worries me. Read a few things online and some people said it could be a rod. However if it's a rod,wouldn't it decrease with acceleration? I've included a link to the video of it idling, the sound in the video is pretty accurate as to what I hear in person. It's a noticeable loud clanking.

https://youtu.be/I8cbp7Zm2Fw

Any idea what it could be and what this could cost me?

This past year I had the radiator replaced and a head gasket job,which set me back half of what this truck is worth...I purchased this for the "reliable" engine and it's given me more trouble than when I used to own a VW, which says a lot.Any advice would be appreciated, thanks!

 

Doesn't sound good, start by checking your oil and make sure it didn't get ran down too low. Engines burn oil as they age so it's something you really need to keep an eye on in a higher mileage vehicle. That knock doesn't sound good at all. These engines are extremely reliable but like anything need to be kept up on maintenance but no matter how well you take care of it, nothing lasts forever. Luckily though used engines are easy to come by and relatively reasonable for low mileage specimens. Not hard to swap out an old engine and slap a new one into one of these trucks either. They were made when things were still relatively simple and easy to work on. I can't imagine attempting an engine swap on a 2016 Tacoma though, those things look like a total clusterf**k under the hood.

 

I just had the oil changed through toyota less than 500miles ago, I did check the dipstick when I first heard the noise and it was fine.
I guess I'll throw in the only history I know in case that matters;

I have routine oil changes&check ups every 3k miles and I've owned this for about two years now. Purchased it used, within a few months the radiator blew,as soon as it happened I was towed and I didn't continue to run it hot. A few months after that the spark plugs were replaced, because I kept getting code p0303 and p0300.. Eventually it started smoking and the head gasket went.

With already so much money into this engine.. I'm reluctant to swap it out. I figured it would last me another 100k miles..
Gonna have a shop look at it in the morning and see what they say..

 

Sounds like rod knock.

Most likely caused by oil starvation/obstruction.

 

Sure sounds like a rod knock to me.

 

Where do you take it to get the oil changed? If the oil was okay the oil filter itself could have failed. Crappy filters like the Orange Can of Death (FRAM) are time bombs waiting to happen and many quick oil change shops use low quality filters like Fram to save money. A bad oil filter can lead to premature engine failure, that's something you might want to look into since the oil level is fine.

 

@2004TacomaSR5 this last time I took it to the toyota dealership for an oil change because I was out of town. Usually I take it to my local shop,which focuses on toyota and foreign. They've done all my work up til now. I'm currently out of town right now ..i had it towed to a shop up the road which should look at it tomorrow..

@cmj @fxntime if it was a rod knock, technically it wouldn't get louder & faster with acceleration though correct?
I find it hard to believe it's from oil starvation when I've always kept the fluids maintained, hmm.. Thanks for your help!

 

As the engine RPM's rise, so would the speed of the knocking.

The speed would rise and drop with the RPM of the engine. That is classic textbook rod knock.

 

fan clutch, fan blade, and shroud. just open your hood and wiggle the blade. any looseness indicates a problem. it should be free spinning with some resistance btw (if no resistance, you need to change it anyways), but it shouldn't tilt or move forward and back.

you may also want to check your motor mounts. I hit a jump in my 06 taco and landed straight into the next burm. heard a loud clacking noise that slowly went away over time. turned out i hit the burm with so much force that it bent the motor mount support that was welded on the frame and dropped the driver side mount almost an inch or so. this caused the fan to tilt down and rub the inside of the shroud. and it also caused the bottom of the engine to smack a return fitting on the rack and pinion, punching a 1/4 inch hole into it.... patched it up with JB weld since it was leaking my oil.