manual transmission fluid for FI
manual transmission fluid for FI
For those that are FI and have m/t's what brand of transmission fluid do you use?
Should genuine nissan fluid be used or is a race grade fluid recommended for the added power association with FI?
I have been using oem fluid, but am considering using Silkolene syn 5 75w90..:
http://www.silkoleneoil.com/pdf/SILK...04%20Wheel.pdf
Should genuine nissan fluid be used or is a race grade fluid recommended for the added power association with FI?
I have been using oem fluid, but am considering using Silkolene syn 5 75w90..:
http://www.silkoleneoil.com/pdf/SILK...04%20Wheel.pdf
I use royal purple also, saved my rear end when my second trans went bad because of its heat properties.
I know alot of big supra guys out by me swear by the Royal Purple. The only other one I would consider would be the Motul 300 gear oil.
I know alot of big supra guys out by me swear by the Royal Purple. The only other one I would consider would be the Motul 300 gear oil.
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prestone 50/50, spending big money on special coolant is pointless, if you have cooling issues you should be addressing your cooling system, not what's in it.
thx for the advice. I don't have cooling issues, Just planning on doing some fluid changes (last time they were done was before I was FI). ARC radiator and ARC oil pan have served my car well.
Jonny,
I keep meaning to write a fairly extensive post about transmission and gear oils, but i just never find the time to sit down and do it. That being said, I have had very good experience with Silkolene as they are one of the few companies to have forwarded my questions on to a chemist in England who was very cool to chat with. He essentially confirmed what several SAE papers and lubricant books have espoused, which is the fact that GL-5 is not backwards compatible to GL-4. Many people on the internet are misunderstanding this to mean that one is more corrosive to yellow metals, and this is not really an issue. Just about all GL-5 oils have inhibitors and buffers to prevent the chemical corrosion of yellow metals which extreme pressure additives rely on to do their job. That is to say that the oil works to corrode the surface of the metal through chemical alteration of the surface, producing a more durable compound on the metal's surface which resists wear. This chemical reaction will produce a hardened surface on some ferrous metals, while pitting yellow metals due to the inability of the altered structure to continue adhering to the parent material. Again, most GL-5 oils have buffers to protect the yellow metals, and will pass a copper corrosion test with a 1b rating. Silkolene Syn5 is no different in this regard. The reason why GL-5 is a separate grade then, and should not be used, is because the ant-wear and friction modifiers are of an altogether different content and higher amount. This reduces wear and friction for hypoid gear use, but does not allow the frictional properties necessary for smooth synchro engagement. The force transmitted between the synchros relies on friction to match speeds for engagement, and oils which meet GL-5 are not designed to allow the specified frictional characteristics of a transmission spec'd for GL-4. The reason many companies put a GL-4/GL-5 rating on their gear oils is because the consumer is not familiar with the MIL spec which certifies a GL-5 as safe for use with yellow metals, and so they convey the high anti-wear and friction modified properties of the GL-5 with the yellow protection assumed with a GL-4. The fact is, the two roles of the fluid could not be more different. The Silkolene chemist did not recommend their Syn5 oil for the transmission for this reason. it will not damage the transmission, but it is not ideal and will lead to faster wear of the synchros than if I use a specified GL-4 oil. His recommendation was to try SRG75, which I will probably do.
When you change the stock transmission oil, it will be much more clear and not stink as bad as the oil coming from the differential. The color and smell are the result of the different amount and type of additives used in each oil. If you replace the transmission oil, try to use a GL-4 oil like the SRG75, or Redline GL-4 transmission oils. Amsoil also has dedicated GL-4 oils. The viscosity can be varied, and I tend to prefer lighter oils since the oil must both be evacuated from the synchro engagement teeth very quickly during a shift, and must flow well when cold. A thinner gear oil with good base stocks and proper additives will better facilitate both of these measures while also running cooler. As I recall, SRG75 is around 10.8 cSt, which a hair lighter than stock fluid. Redline MTL and MT90 can be mixed for a similar overall grade. One downside with lighter fluid is a noisier gearbox, but do not be fooled into thinking that a lighter fluid means less protection. That is more to do with chemistry than viscosity, and the Silkolene, Redline, and Amsoil products are all top notch in this regard. You couldn't go wrong with any of them.
Will
I keep meaning to write a fairly extensive post about transmission and gear oils, but i just never find the time to sit down and do it. That being said, I have had very good experience with Silkolene as they are one of the few companies to have forwarded my questions on to a chemist in England who was very cool to chat with. He essentially confirmed what several SAE papers and lubricant books have espoused, which is the fact that GL-5 is not backwards compatible to GL-4. Many people on the internet are misunderstanding this to mean that one is more corrosive to yellow metals, and this is not really an issue. Just about all GL-5 oils have inhibitors and buffers to prevent the chemical corrosion of yellow metals which extreme pressure additives rely on to do their job. That is to say that the oil works to corrode the surface of the metal through chemical alteration of the surface, producing a more durable compound on the metal's surface which resists wear. This chemical reaction will produce a hardened surface on some ferrous metals, while pitting yellow metals due to the inability of the altered structure to continue adhering to the parent material. Again, most GL-5 oils have buffers to protect the yellow metals, and will pass a copper corrosion test with a 1b rating. Silkolene Syn5 is no different in this regard. The reason why GL-5 is a separate grade then, and should not be used, is because the ant-wear and friction modifiers are of an altogether different content and higher amount. This reduces wear and friction for hypoid gear use, but does not allow the frictional properties necessary for smooth synchro engagement. The force transmitted between the synchros relies on friction to match speeds for engagement, and oils which meet GL-5 are not designed to allow the specified frictional characteristics of a transmission spec'd for GL-4. The reason many companies put a GL-4/GL-5 rating on their gear oils is because the consumer is not familiar with the MIL spec which certifies a GL-5 as safe for use with yellow metals, and so they convey the high anti-wear and friction modified properties of the GL-5 with the yellow protection assumed with a GL-4. The fact is, the two roles of the fluid could not be more different. The Silkolene chemist did not recommend their Syn5 oil for the transmission for this reason. it will not damage the transmission, but it is not ideal and will lead to faster wear of the synchros than if I use a specified GL-4 oil. His recommendation was to try SRG75, which I will probably do.
When you change the stock transmission oil, it will be much more clear and not stink as bad as the oil coming from the differential. The color and smell are the result of the different amount and type of additives used in each oil. If you replace the transmission oil, try to use a GL-4 oil like the SRG75, or Redline GL-4 transmission oils. Amsoil also has dedicated GL-4 oils. The viscosity can be varied, and I tend to prefer lighter oils since the oil must both be evacuated from the synchro engagement teeth very quickly during a shift, and must flow well when cold. A thinner gear oil with good base stocks and proper additives will better facilitate both of these measures while also running cooler. As I recall, SRG75 is around 10.8 cSt, which a hair lighter than stock fluid. Redline MTL and MT90 can be mixed for a similar overall grade. One downside with lighter fluid is a noisier gearbox, but do not be fooled into thinking that a lighter fluid means less protection. That is more to do with chemistry than viscosity, and the Silkolene, Redline, and Amsoil products are all top notch in this regard. You couldn't go wrong with any of them.
Will
Jonny,
I keep meaning to write a fairly extensive post about transmission and gear oils, but i just never find the time to sit down and do it. That being said, I have had very good experience with Silkolene as they are one of the few companies to have forwarded my questions on to a chemist in England who was very cool to chat with. He essentially confirmed what several SAE papers and lubricant books have espoused, which is the fact that GL-5 is not backwards compatible to GL-4. Many people on the internet are misunderstanding this to mean that one is more corrosive to yellow metals, and this is not really an issue. Just about all GL-5 oils have inhibitors and buffers to prevent the chemical corrosion of yellow metals which extreme pressure additives rely on to do their job. That is to say that the oil works to corrode the surface of the metal through chemical alteration of the surface, producing a more durable compound on the metal's surface which resists wear. This chemical reaction will produce a hardened surface on some ferrous metals, while pitting yellow metals due to the inability of the altered structure to continue adhering to the parent material. Again, most GL-5 oils have buffers to protect the yellow metals, and will pass a copper corrosion test with a 1b rating. Silkolene Syn5 is no different in this regard. The reason why GL-5 is a separate grade then, and should not be used, is because the ant-wear and friction modifiers are of an altogether different content and higher amount. This reduces wear and friction for hypoid gear use, but does not allow the frictional properties necessary for smooth synchro engagement. The force transmitted between the synchros relies on friction to match speeds for engagement, and oils which meet GL-5 are not designed to allow the specified frictional characteristics of a transmission spec'd for GL-4. The reason many companies put a GL-4/GL-5 rating on their gear oils is because the consumer is not familiar with the MIL spec which certifies a GL-5 as safe for use with yellow metals, and so they convey the high anti-wear and friction modified properties of the GL-5 with the yellow protection assumed with a GL-4. The fact is, the two roles of the fluid could not be more different. The Silkolene chemist did not recommend their Syn5 oil for the transmission for this reason. it will not damage the transmission, but it is not ideal and will lead to faster wear of the synchros than if I use a specified GL-4 oil. His recommendation was to try SRG75, which I will probably do.
When you change the stock transmission oil, it will be much more clear and not stink as bad as the oil coming from the differential. The color and smell are the result of the different amount and type of additives used in each oil. If you replace the transmission oil, try to use a GL-4 oil like the SRG75, or Redline GL-4 transmission oils. Amsoil also has dedicated GL-4 oils. The viscosity can be varied, and I tend to prefer lighter oils since the oil must both be evacuated from the synchro engagement teeth very quickly during a shift, and must flow well when cold. A thinner gear oil with good base stocks and proper additives will better facilitate both of these measures while also running cooler. As I recall, SRG75 is around 10.8 cSt, which a hair lighter than stock fluid. Redline MTL and MT90 can be mixed for a similar overall grade. One downside with lighter fluid is a noisier gearbox, but do not be fooled into thinking that a lighter fluid means less protection. That is more to do with chemistry than viscosity, and the Silkolene, Redline, and Amsoil products are all top notch in this regard. You couldn't go wrong with any of them.
Will
I keep meaning to write a fairly extensive post about transmission and gear oils, but i just never find the time to sit down and do it. That being said, I have had very good experience with Silkolene as they are one of the few companies to have forwarded my questions on to a chemist in England who was very cool to chat with. He essentially confirmed what several SAE papers and lubricant books have espoused, which is the fact that GL-5 is not backwards compatible to GL-4. Many people on the internet are misunderstanding this to mean that one is more corrosive to yellow metals, and this is not really an issue. Just about all GL-5 oils have inhibitors and buffers to prevent the chemical corrosion of yellow metals which extreme pressure additives rely on to do their job. That is to say that the oil works to corrode the surface of the metal through chemical alteration of the surface, producing a more durable compound on the metal's surface which resists wear. This chemical reaction will produce a hardened surface on some ferrous metals, while pitting yellow metals due to the inability of the altered structure to continue adhering to the parent material. Again, most GL-5 oils have buffers to protect the yellow metals, and will pass a copper corrosion test with a 1b rating. Silkolene Syn5 is no different in this regard. The reason why GL-5 is a separate grade then, and should not be used, is because the ant-wear and friction modifiers are of an altogether different content and higher amount. This reduces wear and friction for hypoid gear use, but does not allow the frictional properties necessary for smooth synchro engagement. The force transmitted between the synchros relies on friction to match speeds for engagement, and oils which meet GL-5 are not designed to allow the specified frictional characteristics of a transmission spec'd for GL-4. The reason many companies put a GL-4/GL-5 rating on their gear oils is because the consumer is not familiar with the MIL spec which certifies a GL-5 as safe for use with yellow metals, and so they convey the high anti-wear and friction modified properties of the GL-5 with the yellow protection assumed with a GL-4. The fact is, the two roles of the fluid could not be more different. The Silkolene chemist did not recommend their Syn5 oil for the transmission for this reason. it will not damage the transmission, but it is not ideal and will lead to faster wear of the synchros than if I use a specified GL-4 oil. His recommendation was to try SRG75, which I will probably do.
When you change the stock transmission oil, it will be much more clear and not stink as bad as the oil coming from the differential. The color and smell are the result of the different amount and type of additives used in each oil. If you replace the transmission oil, try to use a GL-4 oil like the SRG75, or Redline GL-4 transmission oils. Amsoil also has dedicated GL-4 oils. The viscosity can be varied, and I tend to prefer lighter oils since the oil must both be evacuated from the synchro engagement teeth very quickly during a shift, and must flow well when cold. A thinner gear oil with good base stocks and proper additives will better facilitate both of these measures while also running cooler. As I recall, SRG75 is around 10.8 cSt, which a hair lighter than stock fluid. Redline MTL and MT90 can be mixed for a similar overall grade. One downside with lighter fluid is a noisier gearbox, but do not be fooled into thinking that a lighter fluid means less protection. That is more to do with chemistry than viscosity, and the Silkolene, Redline, and Amsoil products are all top notch in this regard. You couldn't go wrong with any of them.
Will
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