Is there a manual transmission fluid that anyone might recommend for a front wheel drive Kia that specs a 75-85 gl-4 gear fluid? No one local carries it or even heard of it, and mostly what I find online is Redline, which I'm sure is good. Not sure if the factory fill is synthetic or not, but seeing as how the car has 100,000 miles and it has never been changed, I may have to run a change through it to flush out the old factory stuff. Is there a gl-5 that is known to be very easy on the yellow metals? I would like to switch it to synthetic for the smoother shifts, but I seem to remember seeing a test on a website where the Lucas synthetic was about the most corrosive on yellow metals out of the whole group being tested. If need be I can go to the dealer, but would like to see what you guys may suggest. I would like to run a fill of cheaper synthetic gl-5 gear oil due to availability and low cost just clean out the gearbox, but I don't want to try anything without checking with you guys first!!!
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