What is everyone using in their oil bath Hyatts nowadays? Mineral oil is spec’d but they provide no approved suppliers. Have some wheels to swap out and they have Hyatts.

Texaco Journaltex HD57 or equivalent. I have also have had no issues with American Refining Group ArGuard journal oils or their zinc free EMD multi-grade lube oils.

EBL

Chevron recently changed the product name:
was: Chevron Texaco JournalTex HD 57
now: Chevron Regal HD 57

Website https://www.chevronlubricants.com/en_us/home/products/regal-hd-57.html
Datasheet https://cglapps.chevron.com/msdspds/PDSDetailPage.aspx?docDataId=323769&docFormat=PDF

- Doug Debs

Thanks guys. We have Interlube Journal Guard AYG on hand. My assumption is that it’s equivalent.

Always consider lubrication recommendations found in literature from the period of apparatus to be obsolete, particularly if the literature predates 1985.

I would only caution that at least in the automotive/truck world, manufacturers and vendors will out of convenience or ignorance will list modern replacements for old products that aren't necessarily correct. Most sources will list GL5 gear oil for Muncie and Borg Warner T10 transmissions because that is what they make or sell, but the correct product is GL4, which only a few people still
Make.

That’s why I asked the question. The old Hyatt manuals I have spec mineral oil with the appropriate viscosities without any product recommendations. It got me to thinking as I couldn’t exactly recall what we used back in the excursion days. I thought it might have been journal oil but I was still sort of a noob/gofer and didn’t pay close enough attention to what they were using while I was doing other work on the cars.