Was GL-5 even available back in 1992? Back then the dealers were adding GM's LSD additive. I can't find any info on Mitsubishi's spec of 8149630EX.

Right now I've got Moble1 75w-90 in the diff. It comes with the LSD additive and is classed as a GL-5. I was still getting some minor diff chatter/shudder on some from-a-stop sharp turns. I added an oz of LSD additive but still the chatter continued. I added a little more but can't get rid of the chatter/shudder. It's been 30K since last change so want to do something different.

I've emailed Redline on their MT-90 GL-4 but I'll have to add the LSD additive. Redline is so darn expensive though.

Do these diffs/transfer cases have brass?