Tranny and Diff fluid

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plrgpr
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Tranny and Diff fluid

Post by plrgpr »

I read here on the forum that my 66 4-sp the transmission and differential “share” fluid. But in the service manual it shows two different drain plugs and fill points and calls for two different oils and quantities, what’s up with that? Also, everyone on the forum says to use GL-4 only in the trans but GL-5 is OK for the diff.
How can that be if they “share”. BTW, GL-4 seems very difficult to find at local parts stores. Where do you guys get GL-4?
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Re: Tranny and Diff fluid

Post by terribleted »

You can not use any GL5 spec in a Corvair standard shift transaxle. You could use it in an automatic equipped car as it will not hurt the diff but will hurt the standard trans which shares fluid with the diff. I have taken to ordering my GL4 lube online. I have been using Sta-Lube 85w90 GL4. I have no noticed any issue nor have any of the cars I have installed this fluid in reported any issues, but, I have seen that 75w-90 seems better to some (did not note the brand on this).
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
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plrgpr
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Re: Tranny and Diff fluid

Post by plrgpr »

Ted, but do the trans & diff share fluid? In the manual, it appears you have to drain both and fill both and the service manual calls out different fluids for each, yet I read on the forum that they share fluid. I plan on using Redline MT90 gear oil. We have been using it in our race cars and it’s GL-4. It specifically states that there are no reactive sulfers that cause damage. If they don’t share, do you use the same fluid in the trans and diff?
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Re: Tranny and Diff fluid

Post by bbodie52 »

GL-4 lubricant can be easily found from sources like Amazon.com, but is somewhat more difficult to find in local retail stores, which tend to limit their store inventory to only the items that are currently in heavier demand.

:link: https://www.amazon.com/s?k=gl-4+gear+oi ... b_ss_i_1_4
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.
Image

:link: http://www.corvairforum.com/forum/viewt ... red#p75164

GL-5 would be permissible in a Corvair differential that is attached to a Powerglide Automatic transmission, since the differential does not contain any "yellow metal" components, and the Powerglide transmission fluid is not shared with the differential.
Also see: :link: http://www.corvairforum.com/forum/viewt ... =80&t=8549

and :link: http://www.corvairforum.com/forum/viewt ... al#p101522 if you really want to dig into this subject about GL-4 vs. GL-5 lubricants.


The manual transmissions never had a drain plug, but the early differentials did. GM eliminated the drain plug from the differentials in later model Corvairs (unfortunately), making it difficult to change transaxle fluid.

Image
Image

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

BE SURE TO ONLY FILL YOUR DIFFERENTIAL AND MANUAL TRANSMISSION WITH GL-4 GEAR LUBE. GL-5 gear lube will damage the "yellow metal" components in your manual transmission. The Corvair transaxle shares gear oil between the manual transmission and the differential, so the gear lube must be GL-4 in both.

ImageImage


jmikulec wrote:Thu May 18, 2017 11:04 pm

...Also, how do I change the gear oil or do I even need to? What oil is best?
The 1965 Corvair Chassis Shop Manual (section attached) specifies using SAE 80 GL Multi-purpose Gear Lubricant. Gearbox oils are classified by the American Petroleum Institute using API GL ratings. Gear lubricant is now available in both GL-4 and GL-5.
:link: https://en.wikipedia.org/wiki/Gear_oil
The difference between the two standards is discussed in the attached technical paper. The main thing you need to know is that either GL-4 or GL-5 can be used in a Corvair differential THAT IS ATTACHED TO A POWERGLIDE TRANSMISSION ONLY! GL-5 is not compatible with the '"yellow metals" found in the manual transmissions. Since the gear lubricant in a manual transmission Corvair transaxle is shared between the transmission section and the differential section, ONLY GL-4 GEAR LUBE SHOULD BE USED IN A CORVAIR MANUAL TRANSMISSION-EQUPPED TRANSAXLE.

According to the SPECIFICATIONS section (attached), the Rear Axle has a capacity of 4½ pints. The 3-speed Manual Transmission has a capacity of 2.2 pints, and the 4-speed has a capacity of 3.6 pints. (In 1966 a different manual transmission was introduced — I don't have the capacity for that unit, but all manual transmissions and differentials should be filled to the bottom of the threads in the fill plug). The Powerglide Automatic Transmission has a DRY CAPACITY of approximately 13 pints, and an oil pan drain/refill capacity of approximately 6 pints.

Image
:link: http://corvaircenter.com/phorum/read.ph ... 145,115145
keitho64 - Date: January 06, 2008 09:08AM

Hello, time for another stupid question. I was going to drain the oil on my transmission and differential this weekend since I was changing the shifter seal, backup switch and shift coupler. In all my manuals they show a drain plug on the transmission and the differential. On my car there is a flat boss where the differential drain plug should be and I cannot find anything on the transmission. The car in question is a 1964 Monza, 110, 4-speed car.

Am I missing something or were some cars made without drain plugs? Or is there some other way to drain the oil? Outside of siphoning out the oil I do not know what to do.


steve goodman - Date: January 06, 2008 09:35AM

After 1963 the drain plugs were left out of all stick trans and diffs and pg diffs too.

There have been tech tips written about drilling and tapping the bottom of the diff but that is iffy, not much ground clearance. If the diff was apart you could drill and tap the boss for a drain plug but not in the car, the casting is about an inch thick right there.

The typical way is to use a suction gun to pull the old gear lube out. Remember not to overfill when you are done.
66vairguy wrote:Sat Feb 04, 2017 11:53 am

You won't find any statement in the Shop Manual to change the transaxle lube, but it should be changed about every 30K miles depending on use.

Yes you have to pump the lube out - Brad's electric pump looks handy. I've used a wastewater/oil pump that a drill drives sold for restaurants you can find at some hardware stores. A number of cars don't have drains, not just a Corvair thing.

BTW - The number one cause of Corvair transaxle failure is lubricant that is NEVER changed. Even today the local transaxle rebuilder gets units in that have the original factory lubricant (and whatever was used to top them off).

DO NOT USE GL-5 lubricant in a Corvair manual transaxle. The transmission synchros won't like it. Use a GL-4 (no GL-4/5). Some synthetics are rated safe for "yellow metal" transmission parts and have the proper "lubricity" to make the synchros work. Redline makes two, but ONLY one is rated safe for BOTH the transmission AND differential
The Red Line product web site indicates that they make two main categories of gear oil. One category is for differentials (GL-5), and the other is for manual transmissions (GL-4). HOWEVER, THE GL-4 PRODUCT SPECIFICATIONS (SEE BELOW AND THE ATTACHMENT) SPECIFICALLY STATES THAT IT IS NOT FOR USE IN DIFFERENTIALS WITH HYPOID GEARS! This excludes it for use in Corvair differentials. Since one product would be OK for the transmission only, and the other for the differential only, NEITHER PRODUCT IS OK FOR A CORVAIR TRANSAXLE THAT MIXES THE TWO TOGETHER!.

In other words, look elsewhere for a GL-4 product that is truly compatible for a manual transmission that contains "yellow metals" AND has a differential with hypoid gears.

Red Line wrote:GEAR OIL
Red Line makes gear oils for special purposes, not one type to satisfy most fairly well.
:link: https://www.redlineoil.com/gear-lubricants

ABOUT RED LINE GEAR OIL FOR MANUAL TRANSMISSIONS
• Appropriate coefficient of friction for most manual transmission synchronizers (other synthetic gear oils are often too
slippery for proper synchro engagement)
• Red Line offers lubricants to pinpoint nearly every transmission application
• MT-LV, MTL, MT-85 and 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


If you want a synthetic gear lube that would seem fully compatible for a Corvair manual transaxle...
bbodie52 wrote:I would never take the risk of loading GL-5 gear oil into any manual transmission, or into a Corvair transaxle, which does not isolate the differential gear oil from the transmission section. Why would you want to take the risk of damaging your Corvair transmission? GL-5 gear lubricant is fine in a Corvair differential that is part of a Powerglide transaxle, since the automatic transmission is isolated from the differential gear lubricant. But manual transmission transaxles should only use GL-4 gear lube, or the GL-4/GL-5 rated synthetic like the Royal Purple Max Gear synthetic that is specifically formulated to be fully compatible with manual transmissions and the "yellow metals" they contain.
:link: http://www.corvairforum.com/forum/posti ... 5&p=101522
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.

We engineered this ultra-tough, high performance automotive hypoid gear oil to provide maximum protection to heavily loaded gears while maximizing power throughout the drive train. Max Gear outperforms ordinary gear oils by combining the highest quality synthetic oils with Royal Purple’s proprietary Synerlec® additive technology.

Max Gear makes gears run smoother, quieter, cooler and longer without overhauls. A direct reduction of drag in the drive train has huge advantage for trucks and other 4-wheel drive vehicles: better gas mileage. Max Gear is formulated with a friction modifier additive – no additional additives are necessary.

Max Gear is available in the following viscosities: 75W-90, 75W-140, 80W-90, 85W-140 and SAE 90

All Max-Gear oils contain limited-slip friction modifier. Max Gear oils contain the limited-slip friction modifier necessary for proper function of limited-slip differentials. There is no need or benefit to adding additional limited-slip friction modifier


Please email rpautotech@royalpurple.com. Our experts can answer any questions you may have.

For further information or questions please contact Royal Purple technical support directly by email or by phone.
http://www.royalpurpleconsumer.com/contact/
Phone: 281-354-8600
Toll Free: 888-382-6300
:link: https://www.royalpurple.com/product/max_gear/

If you have any doubt, just watch this...
:rolling:
ImageRoyal Purple ROY01300 Max Gear 75W90 Synthetic Lube, 1 Quart
$22.08/qt.
:link: https://www.amazon.com/Royal-Purple-ROY ... 0+gear+oil

ImageRoyal Purple 06300 75w90 Max Gear Oil Case, 6 quart, 1 Pack
$93.92 ($15.65/qt.)
:link: https://www.amazon.com/Royal-Purple-063 ... Z9FXFP989B
Attachments
1961 Chevrolet Corvair Shop Manual - Section 2 - General Lubrication.pdf
1961 Chevrolet Corvair Shop Manual - Section 2 - General Lubrication
(722.9 KiB) Downloaded 35 times
1962-1963 Supplement - Chevrolet Corvair Shop Manual - Section 2 - General Lubrication.pdf
1962-1963 Supplement - Chevrolet Corvair Shop Manual - Section 2 - General Lubrication
(161.33 KiB) Downloaded 38 times
1964 Supplement - Chevrolet Corvair Shop Manual - Section 2 - General Lubrication.pdf
1964 Supplement - Chevrolet Corvair Shop Manual - Section 2 - General Lubrication
(134.91 KiB) Downloaded 43 times
1965 Corvair Chassis Shop Manual - SECTION 0 - GENERAL INFORMATION AND LUBRICATION.pdf
1965 Corvair Chassis Shop Manual - SECTION 0 - GENERAL INFORMATION AND LUBRICATION
(2.94 MiB) Downloaded 37 times
RED LINE MT-LV MT-90 PRODUCT INFO.pdf
RED LINE MT-LV MT-90 PRODUCT INFO
(289.77 KiB) Downloaded 37 times
2016 Royal Purple Catalog Web.pdf
2016 Royal Purple Catalog Web
(6.78 MiB) Downloaded 45 times
Brad Bodie
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Image 1966 Corvair Corsa Convertible

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Re: Tranny and Diff fluid

Post by 66vairguy »

plrgpr wrote:
Sat Jun 22, 2019 7:02 am
Ted, but do the trans & diff share fluid? In the manual, it appears you have to drain both and fill both and the service manual calls out different fluids for each, yet I read on the forum that they share fluid. I plan on using Redline MT90 gear oil. We have been using it in our race cars and it’s GL-4. It specifically states that there are no reactive sulfers that cause damage. If they don’t share, do you use the same fluid in the trans and diff?
As Ted said --- the MANUAL trans and diff share lube (yes they each have a fill because the fluid path between the diff and trans is small - to fill fast you use both fill holes) and a GL-4 is recommended. The automatic (PG) and diff DO NOT SHARE lube and GL-5 can be used in the diff.

The trans axle lube question has been actively discussed on the CCF. The Red Line MT 90 now comes in different types and Red Lines STILL says in their fine print "DO NOT USE MT-90 WITH HYPOID GEARS". The Corvair differential gears are hypoid. Amsoil and Red Line claim to have GL-5 lubes that will work in a transmission, but little data to back it up. WHAT TO DO?

If you are not going racing then the Sta Lube 85W90 works, BUT some have noted the transmission shifts stiffer until warmed up and below 40F it's claimed to make shifting very hard. Note the Corvair spec. is 80W. One of the more affordable 80W lubes is a Brad Penn (or Penn Grade1) 80W90 GL-4 you can order online. It is said to make the Corvair transmission shift nicely. See https://www.summitracing.com/parts/bpo-77296

plrgpr
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Re: Tranny and Diff fluid

Post by plrgpr »

OK, I’ve got 4 qts. of Sta Lube 80w90 GL-4. Going to change the trans and diff oil. Got it through the local NAPA store. They didn't stock it but they got it for me within 3 hrs.
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Re: Tranny and Diff fluid

Post by terribleted »

So you have the transaxle removed from the car? There are not drain plugs in your 66 unit. The only thing you can do is suction pump out what you can from the differential fill hole. IF you removed the trans side cover for access BE CAREFUL, there are parts attached, you want to make sure they go back in right and of course you will need a gasket (you can suck some more fluid from here). If the transaxle is removed you can get it pretty empty by removing the top differential cover and inverting the transaxle.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
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plrgpr
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Re: Tranny and Diff fluid

Post by plrgpr »

No, it’s not out. I was planning on siphoning it out. Not taking the side cover off either. I don’t want to take anything apart if not necessary.
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Re: Tranny and Diff fluid

Post by 66vairguy »

They sell simple oil and water pumps that you connect to a hand drill. That and some simple vinyl tubing will siphon the gear oil out in little time.

I WOULD NOT pull off the side cover on a 66-69 transmission. Unless you're experienced it will be VERY difficult to get the shift forks line up. Even with the gear box out it's tricky. Usually you have to put the gear box on its side and grease the forks so the don't slide out of place (and often fall into the bottom of the transmission - what fun that is - LOL).

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Re: Tranny and Diff fluid

Post by plrgpr »

Thanks for the warning. Side cover will not be coming off!
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Re: Tranny and Diff fluid

Post by RoaringRiverRanger »

Going to change my diff fluid in the 63 Monza 4 spd. I've read through everything above, can I use this:
https://lucasoil.com/products/gear-oil/ ... 0-gear-oil
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Re: Tranny and Diff fluid

Post by terribleted »

NO!!! This is specced for GL5. Gear oil used must not be GL5 for a stick shift Corvair. Click in the tech data sheet and look in the middle of the page where is says...exceeds all GL specifications..second line says API GL5.
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Re: Tranny and Diff fluid

Post by RoaringRiverRanger »

Thanks!! Guess I'll see if I can locate some Brad Penn. I can use Royal Purple listed above tho?
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Re: Tranny and Diff fluid

Post by bbodie52 »

Image


This product states that it is a GL-5 Lubricant — DO NOT USE THIS IN A CORVAIR MANUAL TRANSAXLE (It is hazardous to the "yellow metal" synchros in the transmission).
Lucas Oil Gear Lube Technical Data Sheet Image.jpg
Any lubricant used in a Corvair manual transaxle (differential and manual transmission) MUST be both a GL-4 lubricant AND rated for use in a hypoid gear differential for full compatibility with both the manual transmission "yellow metal" synchros and the hypoid differential gearset.

Image
Image

Image (Its a GL-5 Lubricant!)

ImageImage
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.
PERFORMANCE ADVANTAGES
Severe Service Performance
Max-Gear exceeds Eaton’s stringent GL-5 / MIL-L-2105D Gear Oil Specs. Max-Gear also is safe for GL-4 applications or bronze synchro gears.
Lower Coefficient of Friction
Max-Gear saves energy, reduces temperatures and maximizes power throughput. (OEM or aftermarket limited slip additives are not
required.)
High Temperature Performance
Max-Gear eliminates harmful deposits and extends oil drain intervals.
Low Temperature Fluidity
Max-Gear meeting operating temps for vehicles operating in cold climates
Rapidly Separates From Water
Max-Gear completely separates from water, preventing an oil water emulsion
Meets Warranty Requirements
Max-Gear meets or exceeds OEM warranty requirements for GL-5 automotive rear axle hypoid gear lubrication.

(See attachment ROYAL PURPLE - MAX-GEAR High Performance Gear Oil). IT APPEARS TO MEET OR EXCEED ALL TECHNICAL SPECIFICATIONS... EVEN FOR THE CORVAIR DIFFERENTIAL AND MANUAL TRANSMISSION COMBINED!
:dontknow: :doh: Who would have guessed that this issue would be such a complex topic with so many opinions and pitfalls! :nono:
:link: https://www.royalpurple.com/product/max_gear/
Attachments
TDS_Lucas-SAE-80W-90.pdf
Lucas Oil Technical Data Sheet
(231.75 KiB) Downloaded 13 times
ROYAL PURPLE - MAX-GEAR High Performance Gear Oil.pdf
ROYAL PURPLE - MAX-GEAR High Performance Gear Oil
(226.08 KiB) Downloaded 9 times
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Re: Tranny and Diff fluid

Post by RoaringRiverRanger »

Sorry....just trying to learn, so many DIFFERENT things, options, opinions on these cars AND I want to do it right.
Steve
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Re: Tranny and Diff fluid

Post by bbodie52 »

RoaringRiverRanger wrote: » Sat Aug 22, 2020 11:15 am

Thanks!! Guess I'll see if I can locate some Brad Penn. I can use Royal Purple listed above tho?
The main difference between GL-4 and GL-5 gear oils is the amount of EP additives. ... GL-4 is suitable for hypoid gear service when they are under severe service but are without shock loading. • GL-5 is suitable for hypoid gear service under severe service and shock loads and not for use in a gearbox.

The main difference between GL-4 and GL-5 gear oils is the amount of EP additives. Sulphur/Phosphorus containing products are used as EP-additive. This additive has the purpose to prevent the occurrence of micro-welds on the gear flanks at the local high temperatures which prevail in EP circumstances (temperatures well in excess of 800℃) GL-5 has roughly twice the amount of EP additives compared to GL-4, which is why it is often used in high-pressure circumstances such as in a front axle and rear axle differential.

Sulphur/Phosphorus additives however have an unfavourable property: they can react aggressively towards bronze and copper. This can be disastrous for the synchromesh rings of a gearbox. Therefore it is not recommended to use GL-5 in a gearbox unless the manufacturer allows this.

To conclude:

• GL-4 is suitable for hypoid gear service when they are under severe service but are without shock loading.

• GL-5 is suitable for hypoid gear service under severe service and shock loads and not for use in a gearbox.
Many, if not most passenger cars in our modern world are fitted with automatic transmissions. Manual transmission vehicles are becoming somewhat rare. Regardless of the transmission type, most vehicles utilize a transmission and a differential that are physically separate, so they do not usually share lubricants.

Image
The manual transmission Corvair is somewhat unique, in that it utilized a transmission and a differential that are combined into a single transaxle, AND they share the same lubricant between the two components. The combination of a hypoid gear differential (sometimes with the Positraction limited slip option) AND a manual transmission that utilizes "yellow metal" synchros in the gearbox creates obstacles for the gear oil lubricant manufacturer — in that the lubricant must support a hypoid gearset differential that may have a Positraction limited slip component, and that lubricant cannot be corrosive to the syncros in the manual transmission. (Powerglide automatic transmission-based Corvairs are exempt from this issue, since the automatic transmission component in the transaxle is isolated from the differential and uses a completely different automatic transmission fluid designated Type A, and later, in 1967, DEXRON Type B.

GM Dexron (B) licensed products have a license number on the container that begins with the letter B. Example: B10001. This fluid is backward compatible with all Type "A" Suffix "A", and the Type "A" fluids produced from 1949–1966.
:link: https://en.wikipedia.org/wiki/DEXRON#:~ ... N%20brand.

Since the Corvair transaxle issue is uncommon in modern vehicles, some lubricant manufacturers don't bother to address this issue. Their high performance GL-5 lubricants often exclude use in manual transmissions, hypoid differentials, or limited slip differentials, or some combination of these. The "fine print" on the back of the bottle label, or in the published Technical Data Sheet - Product Design Specification (PDS) must be carefully examined by the Corvair owner.

For Example...

LUCAS OIL GEAR LUBRICANT is strictly GL-5, and not suitable for Corvair Manual Transaxles.

RED LINE GEAR OIL, while perfectly suitable for manual transmissions and is safe for "yellow metal" synchros, further states that MT-LV, MTL, MT-85 and MT-90 are not for use in differentials with hypoid gears. This excludes its use in Corvair manual transaxles.

BRAD PENN/PENNGRADE GEAR LUBRICANT seems to cover both manual transmission synchros and hypoid gears used in the Corvair. BUT... it also states:
Product Description
PennGrade 1® Multi-Purpose ‘Classic’ Gear Oil GL-4 SAE 80W-90 is a specially blended using high quality premium mineral base stocks and select additive technologies. It is designed to be used with “yellow” metallurgy (brass, bronze, copper) and other ‘soft’ metals used in synchronizers,
bushings, thrust washers and other components typically found in classic manual transmissions and transaxles. In applications specifying API GL-4 quality lubricants, use of API GL-5 lubricants with higher extreme pressure additive activity/concentration can damage these ‘soft’ metal components.

It is not intended for use in ‘limited slip’ applications and does not contain friction modifiers which can
interfere with proper synchronizer performance.

PennGrade 1® Multi-Purpose ‘Classic’ Gear Oil GL-4 SAE 80W-90 is recommended for use in such time-honored traditional manual transmissions as
those made by Muncie, Rockwell, NVG/New Process, Borg-Warner, Saginaw and Ford as well as those used in many imports. It is suitable for use in Nissan UD trucks, Mitsubishi Fuso trucks, Volvo trucks and Mercedes Benz truck manual transmissions as well as the transmissions /transaxles on
Nissan cars and SUV’s, Mitsubishi vehicles and Suzuki vehicles calling for an API GL-4 level lubricant. Not for use in applications requiring API GL-5 quality extreme pressure (EP) lubricants or where OEM specialized fluids are mandated. Always consult the equipment owner’s manual for
proper fluid selection
So while it suits most Corvair applications, if you happen to own a Corvair with the Positraction limited slip differential option, Penngrade 1 is apparently not for you!

Image
THE ROYAL PURPLE MAX GEAR product description and Product Design Specification (PDS) would seem to cover all the bases. While this synthetic gear lubricant is somewhat expensive, the transaxle does not require frequent oil changes, so with infrequent purchases the added expense may mean it is not necessarily a significant financial burden.
Are Royal Purple oils compatible with other motor oils?

Yes. Royal Purple lubricants are fully compatible with mineral or synthetic oils. No special procedures are necessary when switching to Royal Purple. We recommend against intentionally creating a mixture of different brands or product lines of engine oils.

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Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible

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