Transmission and differential lubricant and level?
 

Ford Barn members, I have a few questions which are a bit basic but would appreciate your help to make sure get this right:
1. Transmission:
a. '37 case, is the required volume 2.5 pts or __?
b. Full when just below the fill plug hole on side of case?
c. 600W oil, correct?

2. Differential for '33 and '35:
a. Full when 1.5" below the fill plug hole?
b. Volume required?
b. 600W oil, correct?

Thank you and appreciate you being willing to help with these "simple ones".
Steve

Re: Transmission and differential lubricant and level?
 

600 is what the model A guys like. Your 37 has some brass/bronze components inside, and should use a GL 4 type gear lube that is non destructive to the soft metals. 80-90
80-140, depends on where you live, and what your driving habits are. Normal gl 5 in the rear is fine unless you have a columbia in there

Re: Transmission and differential lubricant and level?
 

Thank you cas3, I should have clarified the '37 case has '39 gears in it. I live in Michigan and only drive in the warmer months. I do not have a Columbia. Do you have any further thoughts based on this? Also, is my understanding of "full" correct for trans and differential? Thanks again, Steve

Re: Transmission and differential lubricant and level?
 

Thank you cas3, to clarify my '37 has '39 gears. I live in Michigan and only drive in the warmer months. I do not have a Columbia overdrive. Would the 600W be equivalent to GL 5? Also, based on my clarification do you have additional thoughts? Thanks again, Steve

Re: Transmission and differential lubricant and level?
 

I am not a gear lube engineer, but from what I recall, GL 5 has sulfur in it which makes the lubricant stick to the metal surface. Which is what you want with hypoid gears in a post 31 ford rear end. The sulfur is also whats bad for the soft brass used in the trans syncro blocker rings, and the bronze thrust washers on the ends of the cluster gear.

The 600w is some kinda steam engine oil thats similar to what ford used in the era, very little modern additives in it. Its whats been recommended for A's for all the decades I've been around, and its in my A's too.

Fill the units up to a whisker below the plug hole

Re: Transmission and differential lubricant and level?
 

I'll add, GL 4 is getting hard to find. I've only seen the 85-140 available lately.
When cold, syncro's don't like it. once a few miles are underway its ok.

When I rebuilt my 52 jeep trans a few years ago the jeep guys were saying jeep used mineral oil early on. 3 speed tranny very similar to our Fords. Todays big class 8 trucks mainly run Eaton Fuller transmissions, and they run mineral oil too. So, Thats whats in my jeep. available at NAPA

Re: Transmission and differential lubricant and level?
 

https://www.millersoils.co.uk/produc...assic-vehicle/
Amazon carries some of it.

Re: Transmission and differential lubricant and level?
 

Re: Transmission and differential lubricant and level?
 

Thank you all for the great information. I appreciate your insights. I have found, with Mac's help, that NAPA carries 140W GL-4 for trans and differential. I'll be heading there soon. Thanks again

Re: Transmission and differential lubricant and level?
 

O’Reilly also has it.

https://www.oreillyauto.com/detail/c...oil/mp03/80040

Re: Transmission and differential lubricant and level?
 

Re: Transmission and differential lubricant and level?
 

I use"Sta-Lube" 140 for differential and 85w90 for tranny and Bogg-Warner Overdrive.

Re: Transmission and differential lubricant and level?
 

I add a half bottle of STP each to the trans and the rear.
I use it because it coats the gears and sticks to them. I like to think it helps to protect the gears from condensation when the car sits for long periods over the winter months.

Re: Transmission and differential lubricant and level?
 

One time, when could not find GL-4, the Dollar Store had a mess of it.

Re: Transmission and differential lubricant and level?
 

Good info, I go there often

Re: Transmission and differential lubricant and level?
 

I just bought a gallon of Sta-Lube 85-90w GL-4 at NAPA. It was the only one they had that wasn't really GL-5 but "replacement" for GL-4. Cost about $80.

Re: Transmission and differential lubricant and level?
 

I'm with FRITZ. i the oreillys GL4 gear oil as well. Tom.

Re: Transmission and differential lubricant and level?
 

And............don't forget about Tractor Supply. They stock lots of different gear oils for Ford equipment.

Re: Transmission and differential lubricant and level?
 

https://www.fordbarn.com/forum/attac...3&d=1750820306
https://www.fordbarn.com/forum/attac...4&d=1750820306