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I need help. I have a 1950 standard straight-eight which requires (according to the owner's manual), 90 wt mineral oil in the 3-speed manual transmission and overdrive gearboxes. I can't find any anywhere and everytime I do communicate with someone about it (on the phone or in person) I get silence or funny looks. Any suggestions?

G'day Jacques,
to PackardInfo, I'm sure it's obtainable but being a long way from you I'll let those closer to the action advise.

But....I invite you to include your '50 Standard Eight in the Packard Owners Registry here on PackardInfo.

Just go ask for SAE 90 gear oil, grade GL-1. Common and easily available and pretty much a match for the original lube. It's essentially mineral gear oil with a defoamer added.

That said, many Packard owners use SAE 90-140 EP gear oil (same as you might use in the differential) in the transmission and OD.

For the 90 mineral oil go to an Ag dealer or Ag supplier. The mineral oil is (or was) very widely used in farm tractors for tran/axle/hydraulics. Finding it in anything less than 5 gal containers is not ez tho. Try TSC (Tractor Supply Co.) or the Co-Op (FArmers COop). Walmart sells it (or did at one time) in rural area located stores.

HOWEVER, i would follow Owens advice above about the gear oil GL-1 to replace the Mineral oil.

As for this statement:

"everytime I do communicate with someone about it (on the phone or in person) I get silence or funny looks. Any suggestions"

Understand that over the last 10 to 15 years most of the auto parts stores and dealers are now staffed by people who are strictly "Sales Staff". Their experience level is limited to a two week training course or some 3 month certification at a Jr college. A year ago they were probably Wal-Mart greeters. That's why u get the silence or funny looks. They're training/experience is strictly to sell parts in a store or perform somekind of by-the-book text book procedure. Anything that is not in the training book they have not a clue and therefore never existed or is "not recommended".

The decline of auto parts stores has been sad over the last couple decades. In the San Diego area where I live the critical requirement for a parts salesperson is that they speak spanish. They don't have to know what a car is or how it works. A few months ago I sat in a NAPA store trying to explain to the young salesman what breaker points were and what a dwell meter is. Sad.

If you have a NAPA store nearby, ask for a gallon of 65-201 which will give you the GL-1 he was mentioning. Do NOT use it in your rear axle, however. Get 80W-90 GL-4 for that.

I was experiencing gear "crunching" when shifting into third gear (high) in my 47 Clipper Custom with overdrive. It worked better when the overdrive was engaged because of the freewheeling. During the recommissioning of the car I drained the trans and od and refilled them with 140 weight straight mineral oil I bought from an oil distributor. I settled on 140 instead of 90 weight because of central Texas warm weather. I had to buy a 5 gal bucket. It did not help the crunching.

Several months later I installed new rubber bushings in the clutch anti-chatter rod. The clutch chatter all but disappeared, and the transmission shifted so much better. The high gear shift was without any crunching, just a positive move into the gear. Next garage session with this car I am going to drain the mineral oil and refill with 85W-140 GL5 gear oil. The 140 weight is a bit stiff when cold and this is the only time there is a slight crunching. The 85W-140 weight gear oil should fix this problem.

Wow, that story took a long time to tell. Thanks for your patience.

(o{I}o)

My mistake above, I said SAE 90-140 EP and I should have said 85-140 EP. From the onset of the synchromesh in 1932, it's really a suitable choice for all Packard manual transmissions, overdrives, steering gear boxes and differentials excepting perhaps the 1956 Power-Lok.