got a few problems!?!?!?!

whats up… i have a stock ls motor except for a stage 3 clutch… the problem is whenever I downshift (only when i downshift) i smell burnt oil… im not running a cat… also when i down shift i hear a loud “grinding” noise… im leaning towards throw out bearing which I already purchased… Im mostly worried about the burning oil situation… Im just wondering if a bad pcv valve or something small could cause this… im doing a compression test tommarow.

Check your transmission fluid level.