hey folks. after changing gear oil to 50/50 MT-90/MT-L and Diff to MT-90, im not as pleased as i expected to be w/ regards to the harsh shifting our trannies put out. i went to autobacs in OC and they recommended reg oem oil or non-synthetic because he said syns make the tranny to slippery thus resulting in instable syncros or something like that? instead he suggesed if i was to use non-oem oil, just use a branded dino oil. any comments on this? thanks!

 

I am looking into the same matter myself. It appears that Nissan Tranny uses yellow metal (copper) in various components. Therefore, using GL-5 transmission fluid can cause premature wear. I will probably end up paying for overpriced Nissan OE GL-4 transmission fluid from the dealer.

 

hey n8vz, why not just try using dino oil? like redline or motul? still GL-4

 

Search the forum, one person used Royal Purpal with good results.

 

I have had Royal Purple Max-Gear Oil in my tranny & diff for about a year, maybe a little less. I have been very pleased with the results. The shift gates aren't as notchy as they were before, and the tranny grinds shifts less and less.

I only had the grind occasionally, but in the first few months after I changed to the RP it slowly went away. I can't remember the last time it missed.

 

is that a fact? that royal purple max-gear oil doesnt have the yellow metal corrosive additives in there? because im a very cautious person. btw..i screwed up my diff oil. i used redline mt-90 instead of redline 75w90....do u think thats a serious problem? thanks

 

The quote above was from Royal Purple's website. As I understand it, GL-5 is more demanding on lubrication requirements, but most manufacturers attained the specs using substances that are corrosive to brass & other softer "yellow" metals. GL-4 is not as stringent on lubrication needs, but mandates that it not be corrosive to those metals. I have to assume that when RP says Max-Gear is both GL-5 and GL-4 certified that they are telling the truth. I have had no complaints, I have been pleased with my experiences, but we all have to admit that when we're making lubrication decisions we're talking about long-term results. You do as much research as you can, make your best decision, and hope for the best. I trust Royal Purple. Check out their web site.

As for the wrong diff oil, I don't think it's critical, but I would probably change it to the right stuff when convenient. Probably the worse that will happen with this particular mistake is that you're robbing yourself of a small bit of power & gas mileage. If you decide to go RP in the tranny, just buy enough to do the diff, too. I think (check my math, it has been a while) that 5 quarts did both.