Need Help

[MikeP]

Hi, I was wondering if someone could help me? I have a 62 Corvair with a four speed. just bought. It hasn't ran since 94. I got the engine to turn by hand and now I'm changing all the fluids. When I drained the transmission fluid I had spring and ball bearing fallout. anyone know if where they go? T

[bbodie52]

Welcome to the Corvair Forum!

Much of this answer applies to the TYPE of gear lube you must use in your manual transaxle. THE ANSWER TO YOUR BALL BEARING AND SPRING PROBLEM IS NEAR THE BOTTOM...

I guess when GM engineers dropped the transaxle drain plug to simplify production and to save a little in the cost of manufacturing the Corvair, they assumed that Corvairs only had a life expectancy of 10 years or so and would be junked before they needed a change in transaxle gear lube. History has proven otherwise! Unfortunately, there is no easy way to drain the differential and manual transmission in many Corvairs, which literally sucks!

Tue Nov 07, 2017 11:32 am

... DO NOT USE Redline MT-90 in a Corvair transaxle. Redline's site specifically states that MT-90 is NOT approved for hypoid gears (differential). So it is NOT acceptable for use in a Corvair transaxle since protection for the ring and pinion differential gears is inadequate. Redline does make a modified GL-5 lube that is suppose to work with brass synchronizers called - 75W90 NS GL-5 and states it's approved for transaxles with brass parts. NOTE: Redline NS GL-5 is different vs. their GL-5 which is NOT approved for transaxle use.

I did not know that about their gear lube products. The bottle lable states that it is suitable for transaxles, but the website states otherwise!

https://www.redlineoil.com/mt-90-75w90-gl-4-gear-oil

Since most GL-5 gear oils for differentials are too slippery for manual transmissions, Red Line offers these products that ensure proper shifting while providing ultimate wear protection

Appropriate coefficient of friction for most manual transmission synchronizers (other's synthetic gear oils are often too slippery for proper synchro engagement)
Red Line offers lubricants to pinpoint nearly every transmission application
MTL, MT-85 & MT-90 are not for use in differentials with hypoid gears
Excellent gear and synchro protection, balanced slipperiness for easier shifting in cold climates
Excellent for high- and low-mile transmissions
Compatible with petroleums and other synthetics

And you are using GL-4 gear lube to fill your transaxle, right? NOT GL-5!

My research indicates that Red Line makes two separate gear lubricant products. One is specifically for use in manual transmissions, that include YELLOW METAL synchros. The Red Line gear lube manual transmission oils are rated as GL-4, but the fine print also specifically states that this GL-4 gear lubricant is NOT FOR USE IN HYPOID GEAR DIFFERENTIALS (the Corvair differential uses hypoid gears). The other Red Line gear lubricant products are GL-5 and are for use in differentials, but are not for manual transmissions. Because of this, neither of the Red Line series of gear lube products are suitable for use in a transaxle that shares fluid between the manual transmission section and the differential section.

See the material at the bottom of the following thread: viewtopic.php?f=52&t=15340&p=106565&hil ... ne#p106565

As mentioned in the above thread...

MAX GEAR – HIGH PERFORMANCE SYNTHETIC GEAR OIL
Max Gear – High Performance Synthetic Gear Oil
Max Gear is recommended for use in truck and automotive front or rear differentials, manual transmissions and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid. It is non-corrosive to soft yellow metals (brass, bronze, copper, etc.) and synchronizer safe. Specially designed to extend gear and bearing life, Max Gear provides superior corrosion protection over competing conventional and synthetic gear oils.

Max Gear is available in the following viscosities: 75W-90, 75W-140, 80W-90, 85W-140 and SAE 90
The above product line is from Royal Purple and is a synthetic product. It is not cheap but should work well in a Corvair manual transaxle.

75W-90 Long Life Synthetic Gear Lube

Use AMSOIL Long Life Synthetic Gear Lube in differentials, manual transmissions or other gear applications where one or more of the following standards are specified: API GL-5 & MT-1, MIL-PRF-2105E, Dana* SHAES* 234 (Formerly Eaton* PS-037) for 250,000 miles, Dana SHAES 256 (Formerly Eaton PS-163) for 500,000 miles, Dana SHAES 429A, Mack* GO-J & GO-J+, Meritor* 0-76N (75W-90) & 0-80 (80W-140) plus hypoid gear oil specifications from ZF TE-ML 07A and 08 foreign and domestic manufacturers such as GM*, Ford* and Daimler* Chrysler*. It can also be used in rear axles where API Service GL-4 lubricant is recommended.

So a non-synthetic GL-4 or some of the more-expensive synthetics, like Royal Purple, will do the job for you. The above material should help you to make a selection for your Corvair manual transaxle. Read the fine print carefully! As you can see, many modern products are GL-5, but not necessarily GL-4 for manual transmissions. Some GL-4 transmission lubes are not OK for hypoid differentials. Since the Corvair transaxle needs combine the two, many products will not work. I believe the Royal Purple synthetic gear lube is OK for the Corvair, but somewhat expensive.

With a manual transmission transaxle, the lubricant is shared between the transmission and the differential. The fluid level should be checked in both components, and should be filled up to the bottom of the threads in the fill plug holes. The capacities and recommended fluid type is shown in the specifications section of the Corvair Shop Manual, as shown below. Note that the 3-speed and 4-speed transmissions have a slightly different capacity. These capacities are from the 1965 Chassis Shop Manual, but they apply to earlier Corvairs as well. However, the transmission design changed in 1966, so the 1966-69 manual transmission has a slightly different capacity.

WITH REGARD TO YOUR ORIGINAL QUESTION, I'M GUESSING THAT YOU ARE ASKING ABOUT THE FILL PLUG ON THE SIDE OF THE TRANSMISSION. YOU MAY HAVE REMOVED THE INCORRECT PLUG TO FILL THE TRANSMISSION. SEE BELOW...

I hope my interpretation of your original question is correct. If not, please let me know.

1961-1965 FOUR-SPEED Manual transmission fill plug is circled in black. The DETENT SPRING CAP is circled in RED...

The link below will provide you with a list of useful websites that are Corvair-related. Some of the links will lead you to an extensive technical library that will allow you to download shop manuals and other technical references in Adobe Reader (.pdf) format at no cost. There is also a link that will help you to locate nearby CORSA (Corvair Society of America) club chapters. While the Corvair Forum can be very helpful as you work on your Corvair, having local friends and contacts in your region who are knowledgeable about the Corvair can also be very helpful. These family-friendly CORSA club chapters often offer picnics, group scenic drives, technical training and assistance, car shows, and competition events that can greatly enhance your enjoyment of Corvair ownership. You will also find a list of essential Corvair parts suppliers.

Common and Useful Corvair Websites

viewtopic.php?f=225&t=6007

The link below will provide you with a list of useful websites that are Corvair-related. Some of the links will lead you to an extensive technical library that will allow you to download shop manuals and other technical references in Adobe Reader format at no cost. There is also a link that will help you to locate nearby CORSA (Corvair Society of America) club chapters. You will also find a list of essential Corvair parts suppliers. Clark's Corvair Parts in Shelburne Falls, MA is the biggest and oldest Corvair supplier in the world. You will find a link that can provide you with a series of videos that amount to a tour of the Clark's Corvair Parts facilities. Parts suppliers such as this truly make our Corvair hobby possible.

Common and Useful Corvair Websites

Corvair Forum http://www.corvairforum.com/forum/viewt ... 225&t=6007

I would like to encourage you to expand on your initial post and tell us more about yourself, your Corvair interests, and your goals for your Corvair. Helping us to know more about you will help us to write comments to you that are tailored to your needs and experience. Detailed pictures of your Corvair — including the engine compartment — would possibly be useful. Knowing your location may also suggest possibilities in supporting your Corvair interests.

[terribleted]

What you took off is not a drain plug if a check ball and spring came out. I believe what you removed was a shift point detent ball. Look at the GM 1961 Corvair and Corvair 95 Shop Manual on page 6D-25. Is this what you removed? It goes back in ball then spring then bolt with sealing washer. https://www.corvair.org/chapters/corvan ... rns-61.pdf

[66vairguy]

If your Corvair will be driven normally (not raced) then a regular GL-4 is fine. Some use Sta-lube GL-4 85W90, but is is too thick for cool weather use and I've confirmed it results in hard shifts until the transaxle warms up.

If you don't want to spend a lot of money on fancy "boutique" lubes then you can order Brad Penn (now called Penn Grade) GL-4 80W90 which is the correct gear oil weight for the Corvair transaxle. The oil expert "Richard W." said it's acceptable for the Corvair transaxle.

DO NOT USE lubes labelled GL-4 or 5. They are actually just GL-5 that work in differentials rated for GL-4, BUT ARE NOT APPROVED FOR TRANSMISSION USE.

Note: The confusion at the Red-line site about lubes being O.K. for transaxles, BUT NOT O.K. for hypoid gears is simple --- NOT ALL TRANSAXLES USE HYPOID GEARS as the Corvair DOES! The Redline "NS" is a modified GL-5 that is buffered to supposedly protect "yellow" metal alloys and is "less slippery" to allow the synchronizers to engage properly. At least that is their claim. Some Corvair racers use it and say it's fine, but it is not inexpensive!

[66vairguy]

Congratulation on changing the fluids. As our club transaxle expert says "The number cause of transaxle failures is the result of old dirty lube that was never changed".

If your Corvair will be driven normally (not raced) then a regular GL-4 is fine. Some use Sta-lube GL-4 85W90, but is is too thick for cool weather use and I've confirmed it results in hard shifts until the transaxle warms up.

If you don't want to spend a lot of money on fancy "boutique" lubes then you can order Brad Penn (now called Penn Grade) GL-4 80W90 which is the correct gear oil weight for the Corvair transaxle. The oil expert "Richard W." said it's acceptable for the Corvair transaxle.

DO NOT USE lubes labelled GL-4/5. They are actually just GL-5 that work in differentials rated for GL-4, BUT ARE NOT APPROVED FOR TRANSMISSION USE.

Note: The confusion at the Red-line site about lubes being O.K. for transaxles, BUT NOT O.K. for hypoid gears is simple --- NOT ALL TRANSAXLES USE HYPOID GEARS as the Corvair DOES! The Redline "NS" is a modified GL-5 that is buffered to supposedly protect "yellow" metal alloys and is "less slippery" to allow the synchronizers to engage properly. At least that is their claim. Some Corvair racers use it and say it's fine, but it is not inexpensive!

[MikeP]

Thanks everyone! i appreciate all the responses. This has been very helpful and educational.