Corvair Forum

This is a little complicated and difficult to explain... hope you get what I ‘m trying to ask.

To start off, I’ve taken out my engine and tranny from my 1961 Greenbrier as I’m swapping my 80hp engine to a 102hp.
I think my Greenbrier is a bit of a mix of Corvair’s. When I got it out I noticed the 4 speed gearbox needs renovation. I’m pretty sure it’s not the original tranny. I do have an extra gearbox (that I‘ve been told is from a Greenbrier,see pic). R0123 / GM5 3833182
My question are several...

1. Is the gearbox R0123 / GM5 3833182 correct for a Greenbrier? What is the info about this?

2. can I use without any issues this gearbox (R0123 / GM5 3833182) with the diff 3826196 GM 6?
3. The transmission input shaft that was in the Greenbrier is slightly thinner than the one that goes into the R0123 / GM5 3833182 gearbox. So I will have to use the thicker shaft.

4. I have this diff 3856267 GM 1, but its internally not not OK (rusty).
To summarise... So what was in the Greenbrier was the 3826196 GM 6 diff and GM 3 3788364 4 speed and I want to use the 3826196 GM 6 diff with the R0123 / GM5 3833182 gearbox.

Possible?

Any help appreciate :)




1961 Greenbrier, 1962 Rampside and 1964 Monza cab.

I'm no EM expert, there is a forum for covanatics the covers all the FC's.

See http://www.corvair.org/chapters/corvanatics/ They also have a Facebook page, but as they say --- Facebookevil - LOL.

If you found rust in the diffy, then that's a sign it sat a long time, or maybe someone bought a used unit (that sat for a long time) and installed it.

Mild surface rust on gears can be tolerated for occasional driver vehicles, deep pits will lead to a failure. A hard smooth gear surface is critical for long term durability.

Since I believe you are in Australia, well getting spares is not inexepensive with shipping. As said, if the gear contact surfaces are not pitted, then you can probably manage for occasional use. If the pitting is large or deep, well the hardened surface will start to disintegrate with use.

As I recall --- the FC and car transmissions are very similar, except some of the FC's got a very low first gear for maybe one or two years compared to the car. If you install the later long stroke 164c.i. engine the car ratios work fine. I doubt you'll be hauling large and heavy loads like FC's were designed for when new.

Do note the 64-65 transmissions were revised almost every year. So be very careful when replacing/changing parts.

66vairguy wrote:I'm no EM expert, there is a forum for covanatics the covers all the FC's.

See http://www.corvair.org/chapters/corvanatics/ They also have a Facebook page, but as they say --- Facebookevil - LOL.

If you found rust in the diffy, then that's a sign it sat a long time, or maybe someone bought a used unit (that sat for a long time) and installed it.

Mild surface rust on gears can be tolerated for occasional driver vehicles, deep pits will lead to a failure. A hard smooth gear surface is critical for long term durability.

Since I believe you are in Australia, well getting spares is not inexepensive with shipping. As said, if the gear contact surfaces are not pitted, then you can probably manage for occasional use. If the pitting is large or deep, well the hardened surface will start to disintegrate with use.

As I recall --- the FC and car transmissions are very similar, except some of the FC's got a very low first gear for maybe one or two years compared to the car. If you install the later long stroke 164c.i. engine the car ratios work fine. I doubt you'll be hauling large and heavy loads like FC's were designed for when new.

Do note the 64-65 transmissions were revised almost every year. So be very careful when replacing/changing parts.

Thanks for the input... i live in Sweden and it’s hugely expensive shipping anything over here. Import taxes plus other things usually ends up easily doubling the cost.

I maybe should be clearer... I want to use only the working diff 3826196 GM 6.
This I found parts catalog...
So I assume that 3826196 and 3856267 are the same?

Can’t seem to find any info at all on the 2 gearbox’s. Anyone know?



1961 Greenbrier, 1962 Rampside and 1964 Monza cab.

The parts for 3-4 speed differentials interchange if both are 61-64. Just the outer case is different for 64 provision for the spring perch in the car. The ONLY difference is the input shaft seal is different for 64 (Larger Shaft in transmission that passes through) and possibly the speedo gear if the gear sets are a different ratio. If either is a posi then the ring carrier is longer and the side adjusting ring ( passenger side, it is shallower) has to be kept with the posi carrier if it is swapped.

I actually am in the middle of building a early unit and have taken 4 apart including a PG, which is its own animal.

toms73novass wrote:The parts for 3-4 speed differentials interchange if both are 61-64. Just the outer case is different for 64 provision for the spring perch in the car. The ONLY difference is the input shaft seal is different for 64 (Larger Shaft in transmission that passes through) and possibly the speedo gear if the gear sets are a different ratio. If either is a posi then the ring carrier is longer and the side adjusting ring ( passenger side, it is shallower) has to be kept with the posi carrier if it is swapped.

I actually am in the middle of building a early unit and have taken 4 apart including a PG, which is its own animal.

Thanks for the info :)


1961 Greenbrier, 1962 Rampside and 1964 Monza cab.

OK, I know no that these are just casting numbers... learning all the time :-)

So I can be more specific (I think)...

I have a transmission with this stamped on it...
R0I23
Which means (I think)
R = Saginaw, MI 4-speed manual - January 23rd
I believe it's not possible to know the year? Unless casting number helps?

correct?

I have a Differential with this stamped on it...
HE04 12
Which means (I think)
H = built at the Buffalo plant
E = no idea... help please :-)
04 12 = April 12th
Also I believe it's not possible to know the year? Unless casting number helps?

so transmission R0I23 will work with diff HE04 12?

any help info would be appreciated :-)

The broken transmission has a stamp that begins with ‘HJ’ what d ‘J’ stand for?

1961 Greenbrier, 1962 Rampside and 1964 Monza cab.

O.K. I dragged out the old CORSA tech guide.

Differential code "HE" was used on cars and FC's for 1962-63 models and means --- Manual Transmission case and 3.89 axle ratio.

Differential code "HJ" was for 1962-64 models and means ---- Manual Transmission case, positraction, and 3.55 axle ratio (note the pre-65 positraction units were considered to have a fragile carrier cover that was revised on the 65 and later transaxles to be more durable).

You can move the ring and pinion gears from one transmission to the other, but you need a good press and experience setting up the contact pattern.

This information was compiled by Bob Helt who sadly passed away earlier this week. Bob may be gone, but his legacy of supporting the Corvair lives on.

Differential code numbers are snown on the attached CORSA Corvair Technical Guide 1+2 - Corvair Code Numbers, on page 7.

http://www.corvair.com/user-cgi/catalog ... age=TECH-4



http://www.corvair.com/user-cgi/catalog ... ge=TECH-13





"HJ"is a code that indicates a Manual Transmission (Positraction) differential with a 3.55 Ratio from 1962-1964.

Thanks for the help everyone :)

So I’ll put it all together and get back to you with a big smiley face or a sad one ;)


1961 Greenbrier, 1962 Rampside and 1964 Monza cab.

toms73novass wrote:The parts for 3-4 speed differentials interchange if both are 61-64. Just the outer case is different for 64 provision for the spring perch in the car. The ONLY difference is the input shaft seal is different for 64 (Larger Shaft in transmission that passes through) and possibly the speedo gear if the gear sets are a different ratio. If either is a posi then the ring carrier is longer and the side adjusting ring ( passenger side, it is shallower) has to be kept with the posi carrier if it is swapped.

I actually am in the middle of building a early unit and have taken 4 apart including a PG, which is its own animal.

Question about your cleaning tank:

Is that just a giant metal pot on top of a propane turkey fryer? I have a set of heads I need to hot tank and was going to use a dishwasher but I think I like your setup there. Sorry for hijacking.

Sent from my LG-H931 using Tapatalk

Yes that is exactly what it is, I also have an electric element I use once I get it up to temperature so I don't have to keep turning the turkey fryer dial.

My plan is to use the aircraft simple green in it to clean the heads.

toms73novass wrote:Yes that is exactly what it is, I also have an electric element I use once I get it up to temperature so I don't have to keep turning the turkey fryer dial.

My plan is to use the aircraft simple green in it to clean the heads.

Let me know how that works. I like this.... A lot!

Sent from my LG-H931 using Tapatalk

So not wanting to start a new thread, what is the interchangeability of early differentials? Not looking to change my 4spd but I need a differential for my van.

All the early differentials interchange with the same type of transmission. PG differential to PG transmission and manual transmission to manual differential. The '64s have a leaf spring mount on them and a hole for a dipstick. The '64-'65 FCs have the leaf spring mount but it isn't used.
The main differences that you have to watch out for besides the obvious gear ratios, correct speedometer drive for the gear ratio, posi or not is using the correct seal for the input shaft which got bigger in '64 and has to match the transmission. Early transmissions had 12 teeth on the shaft and '64 and up have 14.

Hi everyone, can you please help,
On the Transmission this number is stamped; RO322
On the Differential this number is stamped; HN 09 04
I have head this transmission is rare and desirable, your professional thoughts if it and what is it worth?
Thank you.