How much time is left on my Transmission?

[duffrey93]

So it sounds like no one has a real definitive answer on which brand to use. Thats fine I will try one or the other or a mixture of them all!

 

So now for flushing. Should I flush the transmission of should I simply change the gear oil? And if I should flush it, what should I flush it with?

[Bassnectar]

Motul gear 300V works awesome in our transmissions, but is costly as hell. and not necessary on a street car. I run synthetic pennzoil 75w-90 in all my families other vehicles (tercel, corolla, ford ranger, altima) and it is great. if you compare the MSDS compared to the motul you can see that it has a higher pour point and lower flash point meaning it will degrade quicker than motul as well as take longer to reach viscosity when cold out but the price is 10$ vs 19$ locally. I wouldn't run a cocktail as yes they will give you better performance right away, but 10k miles down the road it will have degraded much more than using just one fluid.

 

If your subaru doesn't have any performance upgrades what's the point of putting 150$ of transmission fluid in?

 

 

I wouldn't flush anything in the transmission, if your paranoid run a bit of clean gear oil through it as it will flush some extra dirt/metal shavings out.

 

Our transmissions were designed for sl4 fluid, Motul gear 300v is the only fluid I know of that meets sl4 & sl5 at the same time. using a straight sl5 would eat your syncros for lunch

[Hemingway]

If I decide to flush a system, I use the same fluid that is being used in normal operations. If you use a 'cleaner' or other fluid not designed for normal operational use, at a minimum, you run the risk of having residual amounts left in the system. Using an operational fluid (e.g. coolant/water mix, engine oil) elimates this risk and any potential damage to components. If you are really concerned about the cleanliness of a given system, remove it, take it apart, clean it out, reassemble, reinstall.