From what I've read, a GL-5 has twice the sulfer EP additive as a GL-4. So would it be safe to mix 1:1 Mobil 1 75w-90 GL-5 with Mobil 1 0w-40 to create GL-4?
Can you cut a GL-5 to make a GL-4?
- Thread starter glxpassat
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No idea. Is there an aversion to buying a GL4 lube?
Yes, finding it.
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It`s actually really easy to find,most hot rod shops sell it,or it can be ordered online (Amazon,Jegs,etc). Or best yet,order some Amsoil GL4 from a site sponsor here.
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I know you can find it mail order, but if you want it right away...
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Call around to some local hot rod shops or foreign car repair shops and see if they have anything. There`s a few here where I live that carry both Redline MT90,MTL and Amsoil MTG,MTF. There`s a VW repair shop that stocks all Amsoil products here. Some place like that will be your best bet locally.
The problems with GL5s (from what I`ve read) is that the limited slip additives will cause bad shifting action and make your gears crunch/grind. Mobil themselves told me not to use their GL5 gear oils in a manual transmission.
The problems with GL5s (from what I`ve read) is that the limited slip additives will cause bad shifting action and make your gears crunch/grind. Mobil themselves told me not to use their GL5 gear oils in a manual transmission.
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Mixing is far from best.
Really, go online and order the best/most suitable/modern/dedicated fluid that you can.
Really, go online and order the best/most suitable/modern/dedicated fluid that you can.
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Originally Posted By: mechtech2
Mixing is far from best.
Really, go online and order the best/most suitable/modern/dedicated fluid that you can.
^^Absolutely! If you`re going to go through the trouble of changing tranny fluid,do it the right way. Don`t skimp or cut corners. Use Amsoil MTG if you need a GL4.
Mixing is far from best.
Really, go online and order the best/most suitable/modern/dedicated fluid that you can.
^^Absolutely! If you`re going to go through the trouble of changing tranny fluid,do it the right way. Don`t skimp or cut corners. Use Amsoil MTG if you need a GL4.
I've actually thought about this. My trans calls for GL4, 75W85, but synthetic 50 (which is about 75W90) works fine in warm weather.
I carry 5L of Penrite synthetic GL5 75W90 gear oil for axle and portals, and some Delvac 1 5W40. Running out of room for a 20L jug of GL4 synthetic 50 trans fluid.
If I were in a pinch for trans fluid, I'd put in the GL5 Penrite and an equal amount of Delvac 1. I think it would get me to the nearest place I could get the right stuff. It is true that GL4 fluid have about half the EP ingredients of GL5, on average.
I think my gearbox is less likely to leak than any of my 4 portal boxes or 2 diffs, anyways.
Charlie
I carry 5L of Penrite synthetic GL5 75W90 gear oil for axle and portals, and some Delvac 1 5W40. Running out of room for a 20L jug of GL4 synthetic 50 trans fluid.
If I were in a pinch for trans fluid, I'd put in the GL5 Penrite and an equal amount of Delvac 1. I think it would get me to the nearest place I could get the right stuff. It is true that GL4 fluid have about half the EP ingredients of GL5, on average.
I think my gearbox is less likely to leak than any of my 4 portal boxes or 2 diffs, anyways.
Charlie
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The problems with GL5s (from what I`ve read) is that the limited slip additives will cause bad shifting action and make your gears crunch/grind.
Not exactly. GL-5 gear oil is for hypoid gears which have a lot of sliding action along the gear teeth. The antiwear agent that permits the sliding action without wear can be the culprit. Older antiwear chemicals with lots of sulfur damaged the yellow metals (brass, bronze) in the transmission synchronizers. Newer antiwear chemicals in some GL-5 gear oils don't do this damage. Follow the label instructions.
No, don't try to home-brew gear oil. Keep shopping; you'll find either GL-4 gear oil or GL-5 labeled as suitable for manual transmission. Look at the gear oil for outboard motor lower units--that's usually GL-4. An outboard repair shop may have a five gallon pail or larger drum and sell you just as much as you need.
The problems with GL5s (from what I`ve read) is that the limited slip additives will cause bad shifting action and make your gears crunch/grind.
Not exactly. GL-5 gear oil is for hypoid gears which have a lot of sliding action along the gear teeth. The antiwear agent that permits the sliding action without wear can be the culprit. Older antiwear chemicals with lots of sulfur damaged the yellow metals (brass, bronze) in the transmission synchronizers. Newer antiwear chemicals in some GL-5 gear oils don't do this damage. Follow the label instructions.
No, don't try to home-brew gear oil. Keep shopping; you'll find either GL-4 gear oil or GL-5 labeled as suitable for manual transmission. Look at the gear oil for outboard motor lower units--that's usually GL-4. An outboard repair shop may have a five gallon pail or larger drum and sell you just as much as you need.
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