2018 tundra Loud short clatter at cold start up

Short 1-2 seconds of what sounds like valve clatter at cold start up. It does it more when it’s cold but anytime it has set for 8+ hours it will do it. I can immediately turn the truck off and crank again and it doesn’t do it. Its almost like the oil is leaking down and nothing is lubricated when sitting for a while, crank it, takes a second to get lubricated, and then it’s fine until it sits again. The truck runs perfect. No misfires, slow starts, nothing. It’s just this terrible noise. I have ran two cans of seafoam thru it, and last oil change put 5w 30 in it. I live in alabama.

 

Are you sure its the engine? It kind of sounds like the "AC clunk" that alot of people complain about. Do you have your compressor on while you start the truck? How cold is it when it happens?

 

How cold? Mine will sound like the starter doesn’t disengage for a second or 2 when it’s around -10 F or colder. I’m guessing AL isn’t that cold.

 

Def not ac compressor. I have tried cranking with ac on and off. Same thing when it’s cold. And no never gets below 20 degrees here. I just bought the truck in october of 22’ and it’s not even cold here. Had a day or two in the thirty’s but avg temp is probably in the high 40’s. Cold start I’m referring to is truck has just been sitting for a while, and motor is cold.

 

Sounds weird. Usually with sounds like that the thicker oil would help. Does it sound like the chain?

 

If it was the chain I would think it would be consistent. It’s just two seconds or so at start. Also my thinking is if it’s timing chain slap motor would be running off too

 

I believe have experienced this multiple times with my 19 and have yet to figure it out... Just a short burst of "clack clack clack" then nothing until it sits for a few more days...

Truck only has 9600 miles, have had 3-4 oil changes from the dealer and no changes. I ran out of free oil changes recently and it was due (time wise) so I did it myself. Haven't heard the issue since and we just got back from a week long trip, started it up yesterday and no noise.

Only thing that I can think of that is different, I used Mobil 1 oil for my last oil change rather than Toyotas... Who knows if that was the issue but something to look into?

 

Timing chain tensioner/ lifters/ valve clatter. I’m at a loss‍♀️. I have a video but having a hard time uploading it.

 

toyota full synthetic is designed by Mobil 1 for the tundra engine. The 0W20. So same oil. It’s possible during Covid your dealership used something else if they had issues getting the toyota brand 0W20

 

Gotcha... Who knows what the dealership(s) did/used, have a hard time trusting them anymore lol

 

I think the dealers buy whatever they can get in bulk at cheapest. My Lexus dealership uses valvoline according to the sticker and paperwork.

 

Sounds like timing chain tensioners not working. Get a mechanic stethoscope and next cold start, have someone start it up while the probe is on the timing cover.

 

Check this video. He talks common 5.7 engine ticking noises 2-3 times from timecodes ~2 minutes - ~14 minutes.

https://www.youtube.com/watch?v=l2OAHImTgA8&t=772s

 

Research piston slap. It is normal on engines(that does not have tight tolerance) that has not been started for awhile.

 

I have heard this before also. Especially when I was not using the Toyota 0w-20 synthetic oil. Seems like I hardly never hear it anymore. Also, sounds weird, but it seems like it happens when the truck is sitting a little nose down. Who knows!