[1999] Lexus ES300 - rattling under hood (update)

Hello all,

I posted here a couple weeks ago to get some opinions on an issue I had with my car. Here is that thread for reference.

https://www.reddit.com/r/MechanicAdvice/comments/78yp1v/lifters_making_noise_should_i_put_special_oil/?ref=share&ref_source=link

It was suggested in there that I get an oil change as the first thing to try, so I did. It has been about 8 days now since the oil change and I have noticed some differences with the noise.

• The rattling sound (as can be heard in the video from referenced thread) is a lot louder when the car is on drive and I am breaking.

• If I am driving on a straight and not using the breaks, the rattling stops in a couple minutes.

Does this mean anything? The sound was thought to be a lifter in the engine. Does it make sense for the lifter rattle to be louder if I push the breaks and stop if I'm driving with no breaks?

Thanks!

NOTE: I had Full Synthetic oil in there before and now I put Synthetic oil.