Mobil1 GL-5 synthetic gear lubricant LS?


New member
Had a buddy of mine recommend this to me its a, Mobil1 API GL-5 synthetic gear lubricant (limited slip)? Anyways I'm about to change the fluid in my 2010 mk6 golf 5mt (2.5L), and when he had recommended this to me right before pulling the trigger, I got a little skeptical.. Was wondering if anyone had some input on this if they have ever actually used it? Pros/cons? Is my buddy an idiot? Lol. Thanks in advance!


Ready to race!
Never used it, as long as it's 75w90 it should do the job. I would recommend to stick with OEM gearbox oil and also if the transmission works well, I wouldn't change the fluid since it's a "lifetime oil"

Some people used synchromesh and said it was better, but the viscosity is different and leads to gear wearing faster

I personally ran OEM, Royal Purple, Panzoil and AMSOIL. Honestly I feel like the OEM is better quality. Other than OEM, I would recommend RedLine or Motul (GL-4)
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Passed Driver's Ed
I know the 6speed on the GTI takes GL-4. I'm at work and don't have time right now to check on the 5 speed, but I don't believe you should put GL-5 fluid in a box designed for GL-4.


The Fixer
I use it in all my cars. The GTI, the Jeep, older cars. It's been in the GTI for 6 years, it's great. Some say to avoid GL5 because it eats yellow metals like brass, however the Mobil 1 is balanced and stable, this doesn't happen.
'Lifetime oil' is a misnomer, everything breaks down. They consider lifetime to be about 100k.