2003 3.4 287K Broke a rod maybe?

Was sitting about 60 on the highway and it started a slight knock that gradulally got louder over about 30 seconds. Dosent feel like its missing on a cylinder but sounds horrendous.
Examined the filter and the oil contains metal flake.

https://youtube.com/shorts/hdp_cIJR5y0?si=E0t-HfFI-Uf2S43a

I bought it with 4000 miles on it in 2004
Tranmission was replaced about 4 years ago.
Longblock replacment engine and install quote is around $7500
Thats a lot of money to put into a 2003 vechile.
Here's a photo from 2022.

https://drive.google.com/file/d/11rWOMiDBuDVi45lfSEptHPOXchPBwr7w/view?usp=sharing

Not keen on the thoughts of gambling on a Japanse import my mechanic would not even entertain putting one in.

Need a vechile on the road pretty soon (commuting on my 1970 Triumph motorcycle while this gets resolved)

So what do you think that sound is?
Do you think it's worth dropping 7K into?
I don't.

I'm in South Florida the truck is like new underneath.

What would you do?

 

I would try to find a low mileage used engine with a guarantee. Or spend $7500. What kind of good Tundra pickup could you buy for $7500?

 

The only rods you have are connecting rods. It’s running too good for that to be the problem. Could be something valve train related like a broken valve spring. Before going ham on a new motor, pull the valve covers and inspect your cams and associated valve train. Not sure if the 3.4 is buckets or followers, I would guess buckets maybe due to the era that engine was produced.

 

With metal flakes visible in the oil, you can rest assured that you have metal flakes in the bearings for the crank, connecting rods, camshafts and in every associated moving part. Engine rebuild or engine replacement are the only options. Engine replacement gives options of new engine or a previously used, with costs all long that spectrum. Good luck.

 

Grab a beater car for transportation and plan to sell it for about the same as you pay for it after the truck engine is rebuilt. Don't forget to explain the situation to your insurance agent.

 

That noise sounds a LOT like rod bearings after you get detonation from bad gas. Was it "pinging" before this happened? Getting on the highway in warm weather, low load, lower RPM, just crusing and tip into the throttle and hear ping, also known as knock, or detonation? This detonation is when the cylinder fires on its own before the piston hits top dead center and the spark plug fires. As the piston is moving upward, and the cylinder fires on its own like a diesel, puts a MASSIVE amount of kickback into the rod and can bend rods or mushroom the rod bearings.
I had this exact thing happen to me 2 years ago in one of my 4cylinders. Tipping in the throttle 5th gear on a long sweeping on ramp, tipped in to speed up a bit and get the dreaded pinging / detonation so i downshift in order to decrease the load and increase the RPM and the pinging was worse, about two seconds into the pinging in 4th i get that same rattle. The pinging / detonation mushroomed and knocked the rod bearings out of spec and that sound you are hearing is the rod flopping up and down on the crank since the bearings are not holding it tight.
Will it continue to run yes
Will it eventually tear up worse yes
I have heard of people pulling the bottom pan and "rolling" in new rod bearings without a complete disassembly. That doesnt do any good for flushing the engine to get any metal particles out but i have heard of plenty of shade tree mechanics who flushed engines with diesel filling them slam full and cranking it over for a few seconds or running it for a few seconds and draining the diesel to get rid of the stuff from inside the engine before doing two oil changes back to back. This is the "super dirt cheap" way to bandaid it to keep it running a while longer.

 

I don't see how it would run at all with a broken rod. The last time I saw that, the broken rod was punched through the oil pan. Sounds like a top end issue. Not good though.

 

I'd make sure everything is clear of the fan+pullies

 

I agree with the previous response. Assuming you actually need a new engine, buy a used one and pay a mechanic to install it. Should be quite a bit less than $7500.

 

I agree with this actually. I sucked a plastic bag into my clutch fan once and thought all was lost - no, just debris haha

 

Are you guys missing the fact that he found metal in the oil?

 

Well here's the big update. I finally got my truck home from the shop, unfixed, told it likely needed an engine.
Had ordered a mechanics stethascope so traced the sound and it was definately coming from the left head near the back. Pulled out the spark plug and one of the metal posts was missing (they were 2 post plugs)
I fished around with a magnet for a while but couldnt find the bit so i fired it up with the plug out. I assume the fragment got ejected cause when I popped in the new plug all is quiet again.
Its not smoking and runs perfectly.
My machine shop guy says to change the oil and filter and change it again in a week and keep my fingers crossed.

https://ibb.co/Hz7dZ09

Imagine I'd have pulled the engine out for that LOL

 

Damn ... Where'd you buy those plugs?

 

It was one of the stores like O'Rielly or Autozone maybe 30 or 40k back.
Did a compression test this morning 165lb or there abouts on all 6 cylinders not much difference in any of them. I did it cold though I suppose it should have been warmed up. (287k miles)
Put new plugs in it incase any of the others decided to drop a stool on my piston!
Changed the oil and filter, oil pressure looks normal for her which is lower than you would like to see it but apparently thats how they roll and how it always been.
I'll give it another oil change next weekend and she should be good.
So happy after weeks of sweating.

Next timing belt at 360k

 

Congratulations OP, awesome that you fixed it for not much of anything.

The 5vz really gets overlooked amongst Toyota's best engines ever. Absolute tank

 

Man what a lucky(or unlucky) break!? I've heard of this happening with counterfeit plugs but it sounds like you bought them from a reliable source. Strange.

Glad to hear the engine is ok and props to you for solving it on your own.