4 speed oil

[68-500]

Guys get to worked up about this. I would just make sure its got a proper amount of lubricant in it. Its a manual transmission in a light weight vehicle that will most likely never be worked hard for extended intervals. Its gears, roller bearings and synchronizes. Anything from ATF to 85-140. If you don’t like the way it shifts try a different lube.

 

[440+6]

I always used gl4 140, then replaced the guts with passon 4 speed overdrive,
Had the gear installation done by liberty gear, they also modified the blocker rings with square blockers among several other small modifications, anyway it wasent shifting great and Paul at liberty told me to use atf and dont worry he guaranteed no problems.
I went with 2 qts of gl4 90w and 2 qts atf. Within maybee 20 miles it started shifting very smoothly.
Still 50 50 years later and perfect shifts always.

 

[Krooser]

The Chrysler manual was written before synthetic oils were designed for use in street vehicles. Viscosity was the main issue back then, and still should be today. Trust the engineers, synthetics work great in rice-burners and disposable grocery-getters. If you want to protect an old, expensive collector vehicle, use conventional and change it regularly.
So there...Just my 3cents.

As far as GL-5 eating yellow metals...I don't think anyone can say this for sure. It's still an up-in-the-air issue for now.

When I was a British Triumph collector I had a TR3A trans with GL5 lube... the brass syncros went cafluey in 5 years.

Used GL4 from then on... I found a Mobil wholesale house that sold me the GL4 at 1970's prices since that's how old his stock was!

 

[dadsbee]

I always used gl4 140, then replaced the guts with passon 4 speed overdrive,
Had the gear installation done by liberty gear, they also modified the blocker rings with square blockers among several other small modifications, anyway it wasent shifting great and Paul at liberty told me to use atf and dont worry he guaranteed no problems.
I went with 2 qts of gl4 90w and 2 qts atf. Within maybee 20 miles it started shifting very smoothly.
Still 50 50 years later and perfect shifts always.

Nice! I'm running 20W50 engine oil in my Bee. Best that it has ever shifted in my lifetime and that's 49 years of me driving the car... transmission has never been apart. My 66 Sat's 18 spline shifts like ****, my next job is to dump what ever is in it and do the same with it. Wife's Formula S may be next...

 

[440+6]

Nice! I'm running 20W50 engine oil in my Bee. Best that it has ever shifted in my lifetime and that's 49 years of me driving the car... transmission has never been apart. My 66 Sat's 18 spline shifts like ****, my next job is to dump what ever is in it and do the same with it. Wife's Formula S may be next...

Late to reply, I have been told my many smarter than me...(not rjrenton with over complicated answers) just about anything will work fine in these transmissions,
My now formula is 2qts 90 weight gl4 and 2qts atf.
I dare you to find a modern trans that shifts better than mine.
Thing is just about anything is just fine, dad is running 20w50 and all is good.
Lets hear what formula rj gives us?

 

[R413]

Nice! I'm running 20W50 engine oil in my Bee. Best that it has ever shifted in my lifetime and that's 49 years of me driving the car... transmission has never been apart. My 66 Sat's 18 spline shifts like ****, my next job is to dump what ever is in it and do the same with it. Wife's Formula S may be next...

Be interesting to see if oil makes it work better.

58 years later it may be worn from crummy drivers or clutch not released all the way, even with low miles.

 

[Sinitro]

Hmmm..
Shifting easier is one thing but what about internal wear...
Beyond me, I am not a transmission engineer, so I leave it up to (2) of the most experienced A-833 guys..
Wayne Brewer and Jammie Passon, both recommend against using synthetic lubricants, use good,ole 80/90W or 140W GL4...

Just my $0.02...

 

[RemCharger]

Hmmm..
Shifting easier is one thing but what about internal wear...
Beyond me, I am not a transmission engineer, so I leave it up to (2) of the most experienced A-833 guys..
Wayne Brewer and Jammie Passon, both recommend against using synthetic lubricants, use good,ole 80/90W or 140W GL4...

Just my $0.02...

Those guys are buddies/ uncles/grand dads etc to someone.
Therefore: their advice is no good.

 

[Phantomx]

Guys get to worked up about this. I would just make sure its got a proper amount of lubricant in it. Its a manual transmission in a light weight vehicle that will most likely never be worked hard for extended intervals. Its gears, roller bearings and synchronizes. Anything from ATF to 85-140. If you don’t like the way it shifts try a different lube.

My feel exactly. I’ve had gear oil, motor oil, and atf in various old transmissions and they all worked fine. I have an 833 trans in my garage out of a fairly low mile 69 barracuda that came from North Dakota and was last reg’d in 1980 that has atf still in it. That must be a northern state thing.
Travis..