New strange hissing chucking noise coming from 4.7L Tundra

THIS IS RESOLVED, SIMPLE FIX, SEE BELOW...

This title should read "strange hissing chugging sound."

I have 3 Toyotas with the 4.7L motor and know this doesn't sound right. Imaging a rapid shh-shh-shh-shh-shh sound coming from the driver's side of the engine...

Today I did a cold oil change on my 2002 Tundra's 4.7L motor. It's been sitting for 2 weeks and the battery was totally dead, so I also had to jump it. (I'll be installing battery cutoffs on all my vehicles as this is becoming a common theme.) The vehicle is new to me, and it appears the last oil change was 16 months and 5400 miles ago. I meant to do an oil change a few months ago but never got around to it. I have personally only driven this vehicle less than 300 miles in the few months I've had it and it drives strong, sounds strong, no motor issues to my knowledge.

So time today for an oil change. I've done a lot of oil changes so this isn't new for me. I drained the oil for well over an hour, reinstalled the drain plug with washer. The old oil was black, appeared to be conventional, but otherwise unremarkable. It was definitely due for a change. I still have that oil so I can inspect it closer if necessary.

Removed and replaced the oil filter with a new Mobile 1 correct size, and applied oil to the gasket as normal. I added 6.5 quarts of full synthetic 5w30 Costco brand, perhaps a little less actually. I filled the oil filter but spilled perhaps 1/4 - 1/2 of the oil filter amount during installation as it's on a slight angle. I added no more than 6.5 quarts total. I drove it 20 minutes and it drove fine. No issues. Oil pressure when cold was at 1/2, but then when warm dipped down to about 1/4 or slightly lower than 1/4. This seems normal for these Tundras I believe.

Then near the end of my 20 minute drive, I noticed a distinct unusual hissing chugging sound coming from the driver side engine area. I looked underneath and put cardboard under neath, I saw no leaks. I checked the oil pan and oil filter and both were tight. After the vehicle was off, I checked the oil dipstick (parked on street, so it's parked on a slight crown) and it appears in in the normal range. The dipstick and oil cap were on tight. I did not fiddle with anything else other than the oil and the battery, so nothing else is out of place.

But perhaps I dis-lodged some hose or cord loose as I was fussing with the battery jump starter and moving some hoses around to set it near the block for stability. Cords/hoses between the battery and the passenger compartment... I'll go look tomorrow in the daylight to see if anything is loose there.

It's late and dark out now. But I cannot figure out what this noise could be. I'm worried perhaps I over-filled the vehicle.

ANY thoughts?

 

Sounds like it could be a broken vacuum hose.
We expect a full report in the morning.

 

Problem resolved. In typing out the above, it occurred to me I dislodged a hose. I went back out tonight and sure enough, there are some hoses traveling across the gap there between the engine and sidewall on the drivers' side. I don't know what they belong to but one was disconnected. Apparently the weight of the battery charger on those hoses pulled one loose.

I re-connected it, and the noise was gone. I double checked oil level on the warm engine, and it's perfectly in the middle of the range. I drove it 5 minutes and it runs like new... odd sound is gone too. OP now edited as solved.