Foaming gear lube question

[jthorner]

The drivetrain in my 1956 Massey tractor calls for SAE 80 gear oil in the winter, SAE 90 in the summer. I recently changed out all 8 gallons! with fresh GL-5 80W-90 (SuperTech conventional).

This fluid takes care of the transmission, rear differential and PTO (power take off) as well as being used for the internal hydraulic lift system. Works hard for a living

.

When checking the fluid level after a short test run I see lots of little air bubbles, which strikes me as a bad thing. Air does not make a good lubricant.

The shop manual makes no mention of any special requirements, but I am wondering if I need some anti-foaming additive or some such.

Any advice for me?

TIA,
John

 

[MolaKule]

I'm sure it does work hard.

Try to determine how long the bubbles last before they dissipate. If the bubbles or entrapped air goes away in 15 minutes, you're ok. Most GL's have sufficient defoamant to take care of foaming.

Since your oil also serves as hydraulic fluid, check your hydraulic lines and make sure they are tight and that flex hoses aren't porous.