The Viking website says 8 oz of 75w90 or 75w140 Mobil 1 full synthetic gear oil. Which is preferred and why?  Why specifically Mobil 1? Are other brands acceptable?  Happy flying.

Views: 207

Reply to This

Replies to This Discussion

Hey Matt:

We like the Mobile 1 and it has had extensive testing, some other brands tend to foam giving less than desirable outcome. 

Either of the viscosities can be used, the 140 can sometimes not be as readily available, it just gives slightly lower temperatures

Thank you, Alissa

Anyone using Lucas oil additive??

Lucas actually makes a full synthetic 75w140

We have had issues with Lucas foaming - we have tested many without finding anything that lubricates as well as the Mobile 1. As far as we test, we use and what is recommended in the system it is Mobile 1 - anything outside of that we haven't tested long term use and longevity issues. 

Got it changed. I found Mobil 1 75w140 full synthetic and used it. The oil I drained out looked good. Happily flying behind a Viking


New from Zenith:

Zenith Planes For Sale 

Classified listing for buying or selling your Zenith building or flying related stuff...

Custom Instrument Panels
for your Zenith

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, Dynon and Garmin avionics, and more.

Custom Upholstery Kits for your Zenith Aircraft:

Zenith Vinyl Upholstery Kits

Zenith Apparel from EAA:

Zenair Floats

Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

How to videos from

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit for the latest DVD titles.

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Golden Eagle Aviation

Pianosa Flying Farm

Aircraft Spruce & Specialty for all your building and pilot supplies!

© 2021   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service