Strange gushing sound coming from engine

[2001x4.4]

Hi all,

I have a 2001 4.4 sport with 63k on the clock. So far this year (thanks to you guys), I have been able to do the water pump/belts thing, lower front control arms, window regulators, will be doing the front arm bushings this weekend, and now I noticed a strange gushing noise coming from the engine. Took it to my indy the other day and he commented something about the motor oil. Asked me if I used Mobile 1, then he checked the oil level. I replaced my oil every 5k miles. I normally use either Castro or Mobile 1, but this last time, I used Valvoline Synthetic (not sure of the grade).

My question is if the grade of oil can make such a noise or is there something going on in there?

I've spent close to $2k on parts alone this year (my labor). Just wondering if the time is near for a new car.

thanks.