<VV> Finding manual transmission oil locally?

[Hugo Miller]

My Corvairs are 2 spd PG. At least one of my cars has three dipsticks; 
one for engine oil, one for axle oil and one for transmission oil. How 
does that work if axle and transmission are combined? Or is that on 
manual gearboxes only?
If they are combined, it's going to be a trade-off. You want hypoid oil 
in the diff but not in the transmission. I guess that GL4, which is 
'slightly' hypoid as I read it, is as good a compromise as any.
But what happens in all the modern FWD cars that have automatic 
transmission in a combined housing with the differential?
I originally come from the UK and used to work on Minis when they came 
out - they have the transmission gears and differential effectively 
living in the oil pan, all running in the (dirty!) engine oil. The 
differential gear is not hypoid on those however, it is slightly 
helical. Never had any issues with them.


On 2019-06-30 14:43, Bryan Blackwell wrote:
> Corvairs share the lubricant between the trans and diff. You *cannot*
> use ATF, and you *should not* use GL5. I'd suggest finding a place
> that carries GL4, pretty sure Amsoil has one that meets the specs, or
> just order the stuff, there are quite a few vendors who carry Amsoil
> products.
>
> --Bryan
>
>> On Jun 30, 2019, at 8:00 AM, Hugo Miller via VirtualVairs
>> <virtualvairs at corvair.org [1]> wrote:
>>
>> As a general rule, synchromesh transmissions run best on ATF. What
>> you want to avoid is hypoid oil, as this will allow the synchro
>> cones to slip & slide without biting. I have known commercial ZF
>> transmissions become almost underiveable when filled with hypoid
>> oil.
>> The problem is that in the good old days, we had hypoid gear oils
>> and we had EP (extreme pressure) gear oils. So you had EP 90, which
>> was good for synchro transmissions, and Hypoid 90, which was not.
>> The two were quite different.
>> But today, through the magic of modern chemistry, we see EP/hypoid
>> oils, which serve both functions. I would avoid these and use ATF
> or
>> EP 90 if you can find it.
>> I'm not up to speed with the GL numbers - Google will tell you more
>> than I can. Just steer clear of anything with 'hypoid' on the
> label.
>>
>> On 2019-06-30 12:11, John Gull via VirtualVairs wrote:
>>
>>> Well not having any luck finding 75w90 gl4 gear oil for my 65
>>> 4speed
>>> tranny! I can find gl5 oil but according to Richard Widman
>>> website it
>>> is not recommended to use. Any suggestions where to find locally
>>> will
>>> be helpful. Thanks John Gull in Asheville NC
>
>
>
> Links:
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