Motul 300 gear oil (GL4/5) > Redline MT90 .
11-23-2005, 08:29 AM
#24
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And what about the rear??? 75W-90 in motul also...or the same stuff as the front since
it reads 75W-90. Just want to be sure on this so as not to confuse myself and MANY others I'm sure.
11-23-2005, 08:39 AM
#25
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The specs are pretty good...
<center><img src="http://www.miata.net/garage/trans/12.jpg"></center><p>
But still not sure it is ideal.
I would say that as compared to MT90 it wins hands down based on the specs.
But is MT90 the proper fluid for our transmissions? I've been using MTL and find that to be excellent. Motul 300 is a 75W-90. Redline MTL a 70W-80. The viscosity of 300 at 40C is 72.6. The viscosity of MTL at 40C is 56.2. On that basis, MTL seems to be better suited for winter operations. It also seems to be a better match for our transmissions based upon what Audi seems to be using.
I also wonder if the power loss due to the higher viscosity at higher temps is really necessary? Agains, Motul 300 is 15.2 at 100C and redline MTL is 10.6. I don't hear of transmissions failing because the fluid breaks down.
Stephen
But still not sure it is ideal.
I would say that as compared to MT90 it wins hands down based on the specs.
But is MT90 the proper fluid for our transmissions? I've been using MTL and find that to be excellent. Motul 300 is a 75W-90. Redline MTL a 70W-80. The viscosity of 300 at 40C is 72.6. The viscosity of MTL at 40C is 56.2. On that basis, MTL seems to be better suited for winter operations. It also seems to be a better match for our transmissions based upon what Audi seems to be using.
I also wonder if the power loss due to the higher viscosity at higher temps is really necessary? Agains, Motul 300 is 15.2 at 100C and redline MTL is 10.6. I don't hear of transmissions failing because the fluid breaks down.
Stephen
11-23-2005, 08:40 AM
#26
I'd use something else. Just M1 75w90 will be good.
Manual transaxle lubricants have a lot of FMs and such to help synchro engagement which is not needed in the differentials.
Dave
Dave
11-23-2005, 08:44 AM
#27
Uh no sir . . . Redline is not a GL4/5 fluid and does not provide enough EP/AW additives.
Also, the transmissions need a 75w90 for wear reduction. The motul is spot on with OEM fluid in terms of viscosity with it being 1.2 cst thicker @ 100C. Redline is drastically different from OEM.
Dave
Dave
11-23-2005, 08:47 AM
#30
Yes it is, and our trannies do not take a GL4. They take a GL4/5 or a GL4+
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