Timing Chain Rattle Fixed? BG EPR

I've had a timing chain rattle since I purchased my Tundra. Hot and cold, doesn't matter. I've tried switching to a 5w-30, adding MMO for a couple thousand miles, and using the Motor Flush from Walmart. None of it changed the rattle.
I bought some BG EPR and MOA (2 each, cost $60) and thought I'd give it a shot based on some researching I'd done before hand. The oil probably only had 500 miles on it, so it was pretty clean. I dumped the 2 cans of EPR in and ran the engine at around 1800-2000 RPM for 15 minutes then let it idle for 15 minutes. To be clear, the instructions say 1200 RPM for "at least" 10 minutes.
After about 8 minutes the timing chain rattle went away. I didn't get my hopes up because it does that sometimes. I didn't hear it return for the rest of the time running EPR. The drained oil looked like dark coffee. It wasn't cloudy, but it was dark. I filled it back up with 5w-30 and the two cans of BG MOA.
I've only driven it around for two days, but I've experienced no timing chain rattle. I'm hesitant to even post this, but also excited that I might have fixed it...for now.

I'll update the thread if something changes.

P.S. I'm going to add a can of BG ATC to the transmission soon. Last year, while towing, I experience this weird thing where it would not hold a gear and kind of jump between two while going uphill. Not sure this will do anything and I won't get to really test it for a while.

 

Did you have tow haul engaged and the Truck in S4? Towing section has lots of threads on this. https://www.tundras.com/forums/towing-hauling.53/

As for the chain rattle, I have no clue how oil could change that. Isn't it a tensioner issue?

 

Can you give a little back history on the truck? How long have you owned it, mileage when purchased v now? Previous owner maintenance schedule, etc?

Hope this works for you.

 

Yep, I did have tow haul engaged I even dropped down to s3.

As far as the tensioner goes, the popular theory I've read about is that the tensioner gets gummed up with varnish and doesn't work properly. The noise on mine was coming from the drivers side, as it seems is typical.

 

I bought the truck a little over a year ago. I don't know the history as I bought it from Ressler motors in Bozeman and the info they had was pretty sparse. It has a 7 pin connector in the bed and some scratches on the roof. I suspect it hauled around a camper for a bit. It ran/runs well and does all the things I expected of it. We tow a Trailmanor 2720 in the summers. We bought it with around 210,000 miles on it. It now has around 215,000.

 

Everyone I’ve spoken to in the automotive industry (I was a large part of it in my former career) told me engine flushes are for those who want to buy a new motor. Basically they help grande the motor.

I had a bottle of amsoil motor flush but ended up not using it as the reviews said the flush can stay past two or three changes and can have an affect on the oil.

 

Hopefully it holds up for you, but I don’t expect it to be anything more than a bandage fix until you can replace the tensioner. I have the issue myself, but only in very cold temps. MMO (Marvel Mystery Oil) has helped a bit, but I only intend it to get me by until I do the job. Planning on new tensioners, timing chains, etc. as I’ve got nearly 300k km’s on mine. Once I go through all the labour to open it up, might as well. I’d suggest that it would be more useful to others to use full terms for those initialisms.

@1UP The timing chain tensioner is pressurized by engine oil.

 

A concern with doing a "deep clean" of an engines internals would be the filter. Should the cleaning process clog the oil filter to the point of bypass, you run a real risk of starving certain areas of oil. Piston oil holes might be one of those areas.

 

Bg makes some good stuff