Transmission weight, 1931, 60-80-90 series

[tcslr]

What weight is this? 

[EmTee]

Just to be clear, do you want to know how many pounds one of these transmissions weighs, or are you asking about the proper oil 'weight' (i.e., viscosity) to use in the transmission?

[tcslr]

Later not former. Weight of oil.

I should have been more clear. 

[EmTee]

Here's a link to similar discussion that references SAE 250. 

 

https://forums.aaca.org/topic/366943-1931-buick-transmission/#comment-2258491

 

I think that's the original type (others can correct me), but SAE 140 is more readily available and will also work.  I'm running SAE 140 GL-4 in my '38 Century's transmission.  I found it at O'Reilly's.

 

 

Edited May 16, 2023 by EmTee
added link (see edit history)

[Gary_Ash]

I don’t think GL-4 fluids or anything with “extreme pressure “ additives are correct for 1930s (or later) transmissions with brass or bronze parts. The extreme pressure lubes will damage yellow metals. A better choice is synchromesh transmission fluid. Generally, straight 50 weight engine oil also works fine in old transmissions. The extreme pressure stuff is for ring-and-pinion gears in rear axles where the gear surfaces slide against each other. 

[EmTee]

GL-4 will not attack yellow metal, but GL-5 might and should be avoided.

[IFDPete]

How about this 140 weight GL-3 oil from the UK that I found on Amazon $29.99 4L can.  It looked to me like it would be a compatible formula for our older transmissions.  Anyone have an opinion?

Rhino 140

A multi-purpose mild EP gear oil for use in most types of sliding pinion gearboxes. It is particularly suited for use in light to moderately loaded reduction gears,worm gears and certain bevel gears. Widely used in the transmission and final drives of certain older cars and commercial vehicles where its viscosity and lower EP activity are appropriate. Fully compatible with bronze or brass gears, bushes and bearing cages.

• SPECIFICATION

• API GL3

 

https://www.silkolene.com/motorcycle/classic-oils/rhino-140/

 

 

 

[EmTee]

That sounds like it would work. 

[Steve_bigD]

Years ago, I switched from common 75W90 to Sta-Lube SAE 140 in my 38 special transmission and it significantly reduced gear clashing during shifting. I think the older synchros in our cars need a thicker oil.

 

Steve D

 

 

[Brian_Heil]

Modern API certified lubes have anti oxidant stabilizers.  The damaging (oxidation) of the ‘yellow’ metals (it’s actually the copper in them that was once oxidized) is a thing of the past. Cars from the 50s and before that never got their lube updated is why the stories persist. 

[raydurr]

Id like to see someone try to shift my 1929 w 50 wt. You might have to come to a complete stop each gear change. I run that 600 wt Ford stuff in my transmission. I have mixed 85w-140 and STP half and half before for the transmission when the 600 wt wasn't available. It likes thick oil. Rear axle isnt very picky. As long as its heavy and wont erode the brass it should be fine. Most old gear compartments accept heavy lubricants well.