t-19 4-speed fluid type?

[junk]

So I was looking at switching my t-19 4-speed over to sythentic gear lube and started reading about guys running 50w engine oil, 15-50 engine oil, GL-1 gear lube etc in the transmission. And Novak adapters says not to run sythentic in the t-19 because it's a waste of money.

So what oils are you guys running in your old 4-speeds?

My goal with this is to make the 4-speed shift a little better, quiet things down, and maybe gain some MPG.

Thanks
Jeremy

 

[Dieselcrawler]

Just reg old 80-90 gear oil.

 

[theguruat12]

I tried SAE 50, transmission was a bit loud and since I live in NM and AZ, I don't need a thinner fluid, so I'm back to plain 80W90.

 

[IDIoit]

if you wanna run synthetic, and give it a try, i would run royal purple 80W90,
this is what i use in all my diff's
i cannot tell a difference in most, but my LSD's need the friction modifier.
FWIW, i find RP to be a quieter operation in my boats, when the gear box is right beside you.
but they get real loud when a bearing goes kaput, which RP could not help nor bandaid.

luckily Casale engineers their gear box's with conventional bearings.
(V-Drive application)

You must be registered for see images attach

 

[madpogue]

^^^^What's that weird round thing on top with the wires sticking out of it? Must be some extraneous electronics; I'd tear it off......

 

[IDIoit]

those are the new technological pyrometers.
it gauges each cylinder and gives you heat temps in real time.
not to be confused with fuel distributors!

 

[junk]

IDIot - that's a small block ford in the boat right? Distributors at the "front" I don't even build race engines.

Interesting on the royal purple I'll have to look at that. My US gear seams loud when in OD over 65mph. Might try it there first then propagate it to the NP205 and T-19. I am cheap after all.

Thanks for the info guys. Looks like no reason to drain out the gear lube just yet.

 

[IDIoit]

Hahaha

 

[FarmerFrank]

You could put mud in a 4 speed and be golden. I've drained ATF out of them before. Thinner the oil the easier it will shift but the louder it will be. I don't really recommend anything thinner than 15-40 because it will have a hard time splashing any oil.

Also remember engine oil and gear oils are rated on a different scale. gear oil is meant for low shear and high pressure applications ( like between gears)

 

[chris142]

gear oils and motor oils are rated on a different scale. 50w engine oil and 90wt gear oil are the same viscosity. You DO NOT want to run a GL-5 OR GL-6 gear oil in your t19. The anti wear addatives will destroy the brass parts. A differential does not have Brass parts so those oils are a great choice.

You want a SAE50 motor oil or a GL-1 gear oil but the GL-1 is getting hard to fine.

 

[theguruat12]

Considering that the only bronze parts are the synchros, I'm going to live with the GL-5 for now. When I fully rebuild my T-19, it's getting the Royal Purple 80W90 synthetic in it.

Yes, GL-5 rated oils do eat yellow metal, but I have yet to see how long it takes. I think I'll be fine for a year or two.

JM2CW

 

[FordGuy100]

15w40 Amsoil Synthetic in mine. Fine for the last 25k, no difference in sound, and could tell the difference in shifting between it and what I pulled out (likely, the factory fill). Its lived in Oregon and Texas, so it has seen cold (ish) and hot.