Specs on the kodiak call out 80 wieght GL-4 gear lube. Went to the auto parts store and only found GL-5 lube. From what I can tell, the only difference is more sulfur, in the GL5. Anyone know if GL5 is ok to use as a replacement for GL4?

 

Both of these lubricants are used in many different Automotive applications such as manual transmissions and differentials. I used to work for Pennzoil and from what I remember you can not deviate. If it calls for
GL-4 I wouldn't use GL-5.

 

Thats what I was thinking. I found some amsoil 75w-90, rated for gl3 to gl5. Should work out ok, and have the added benifit of flowing easier in cold weather.
Thanks

 

if you look in your owners manual it tells you that gl 4 is a minimum rating and that its ok to use gl 4, 5, or 6.

 

"The most common gear lube is 80-W90 weight oil. The GL designations represent characteristics of the oil. Some are designed for smoother shifting, some for a wider range of operating temperatures and others for improved bearing lubrication. GL5 is used mostly in limited slip differentials and can be used in place of GL4, but NOT vice versa". http://autorepair.about.com/library/faqs/bl904.htm

I use Mobil 1 75W90, which is GL4/GL5. Thinking of switching to Maxima or Redline though.