naishou

I just replaced my transmission fluid with Castrol Syntrans 75W-85. It's a fully synthetic GL4 substitute with the same viscosity as the Honda MTF (10W-30 equivalent). I spoke to Castrol's technical people beforehand to confirm that it is compatible with the Honda gearbox. Unsurprisingly, when I drained the old Honda fluid it smelled and looked just like a regular GL4 fluid.

The reason I did this was to reduce notchy shifting, especially when cold. It's early days yet, but the difference is very noticeable. I no longer feel like I need to baby the transmission and it's as smooth as butter. I have had the fluid replaced once before by Honda and it didn't make this kind of difference. Highly recommended.

xviper

How can a 75W-85 oil have the same viscosity as a 10W-30 oil? What am I missing? Also, how do you suppose this synthetic oil would be at temps down to -35*C? With the stock oil in the tranny, the shifter is very stiff at these low temps.

naishou

[QUOTE]Originally posted by xviper
[B]How can a 75W-85 oil have the same viscosity as a 10W-30 oil?

xviper

Thanks Naishou. How cold is cold where you are? I've never heard of Sydney getting snow so it can't be that cold.

naishou

[QUOTE]Originally posted by xviper
[B]Thanks Naishou.

pfb

This illustrates the point...

pfb

...so next time you need an engine oil change you can go into your local autoparts store and ask for some ISO 22-100 oil

xviper

Ya learn something new every day. Thanks guys.

Allan Haggai

Naishou...I can't find the Castrol 75/85 synthetic gear lube around here. Do you think Mobil 1 75/90 GL 5 is ok for the tranny? Does GL 5 mean that it slightly exceeds the requirements of GL 4?

naishou

[QUOTE]Originally posted by Allan Haggai
[B]Naishou...I can't find the Castrol 75/85 synthetic gear lube around here.