I've been thinking since another user posted and informed me on, that i might of bought the wrong mt fluid for the kia. It is Full Synthetic Valvoline 75W90 gear oil but i believe it is GL5, and not GL4, and to be honest I know very little about MT fluids - but i'm learning fast!.
The plan was to change the current fluid out with the Valvoline 75W90 run for some time, then drain and refill with Amsoil Manual Transmission & Transaxle Gear Lube 75W-90. But if the Valvoline is GL5, (is it backwards compatible with GL4?) or should i skip the pre change, and just go right to Amsoil GL4 Synthetic MT fluid:
Backstory is i called the dealer looking for OEM 75W90 fluid, and they told me they dont sell it by the qt, they only have a 55 gal drum type deal, and to go to autostore and pick up any 75W90 and it will be good to go so i did that not understanding anything regarding GL4/GL5, or anything else about the MT fluid.. Can any one shed some light? Should i return the Valvoline, and just do one change of the MT fluid to Amsoil - then call it good? Its about 23$ a qt, but its not like im changing it out every 5-10K miles. I'd have to order it online, and have it shipped. It seems like all the kia forums highly recommend this fluid for the six speed manual transmission, but i've never personally used Amsoil before... in anything.
I am not trying to correct any issues, no pop outs, grinds, or abnormal notchy-ness, i'm just looking for optimum protection, and to have the MT feel as good as it can get it.
So my questions, is there a fluid locally that I can just pick up and use that is full synthetic and GL4 compatible?
Whats the OCI on a MT fluid? It feels pretty good currently, so im assuming its been replaced in past, with what im not sure. Kia might tell you never to change it, you know "fluid for life" type deal, but it does have drain plug with magnet, and fill port that you put in about 1.9 qts of fluid.
Stick with GL4 Amsoil Synthetic, or would another GL4 synthetic 75W90 work from auto store?
Thanks for all your feedback and suggestions - it never goes unnoticed, i know as one member said im "all over the map" and there is a little truth to that. I try to stay on track, think straight and logical, but sometimes my OCD kicks in to the max, and i just cant lol, and what seems insane to some of you, (like to give the mt a change of fluid before putting in the good fluid thus in turn changing it twice) and things like that. I am working on it.... honestly..

Thanks!.