hydradrive oil gl4 or gl5?

[wildwords]

Hi guys,

just wondering is a SAE 90 GL-5 oil is ok in the Yamaha stern drive ?

In the manual it says SAE 90 GL-4 but in the new brochure for yamaha (link below)

http://www.yamaha-motor.no/no/binary...122-379302.pdf

they spec. GL-5 for the stern dirves?

does anyone have any expiririence using a GL-5 ?

oh and would it matter if you mixed a small amount of GL 4 (left in the pump) ?

thanks

Wildwords

[jwalker]

My understanding is that a GL5 oil is a higher spec than the GL4 and it is pretty well the norm. I'm sure it'll be fine and I doubt a wee drop of GL4 left in the pump will harm. My cars, bike and boat all specify a GL5 gear oil. I use a synthetic GL5 gear oil exclusively. I don't think the lubrication properties are particularly superior but it can withstand considerably higher temperatures which might be a good thing in an outdrive.

[MOS]

Originally Posted by wildwords

Hi guys,

just wondering is a SAE 90 GL-5 oil is ok in the Yamaha stern drive ?

In the manual it says SAE 90 GL-4 but in the new brochure for yamaha (link below)

http://www.yamaha-motor.no/no/binary...122-379302.pdf

they spec. GL-5 for the stern dirves?

does anyone have any expiririence using a GL-5 ?

oh and would it matter if you mixed a small amount of GL 4 (left in the pump) ?

thanks

Wildwords

Only use GL5! The Hydra-drive unit is a very sensitive piece of kit!