<VV> Gear lube level problem

Joel McGregor joel at joelsplace.com
Sat Jul 25 10:00:26 EDT 2015

I should have mentioned the difference so thanks for pointing that out.  I tend to forget that everyone reading doesn't automatically know the difference between EM and LM and that when talking about transmissions the year break is different as you pointed out.

Since transmissions and differentials are designed to run their gears partially submerged in oil all the time the only real problem with overfilling is the possibility of spitting oil out the vent.  The dangers of under filling are failed parts due to lack of lube.  I will always fill to the highest level unless I run across a compelling reason not to.
>From what I've read GM discovered the danger of running too low in transmission problems and hence added the warning to the trans fill plug in '62.
Joel McGregor

From: BobHelt at aol.com [mailto:BobHelt at aol.com]
Subject: Re: <VV> Gear lube level problem

Joel, Smitty,
What you have stated may very well be true and thanks for your comments. But unfortunately you have change the subject of discussion. You have referenced the Early model Corvairs (and '65) that came with that tag located at the tranny filler port.

But the subject was different from that. We were talking about the 1968 transaxle that did NOT come with a tag like the EM's. And the LM 4-spd tranny is an entirely different one from the EM's.  In fact no references were made at all as to checking and filling, except a general one in the SM. So if someone were highly knowledgeable like you, the checking and filling procedure is a snap. My hat is off to you.

 But for the average Corvair guy, it would be a big surprise to find that the lube checking holes are at different levels. And maybe a big surprise too as to which one is at the lowest position in the transaxle.

And so the dilemma as to which one to use for determining the correct lube level. Should I underfill the tranny or, over fill the differential???????     Also comes the question as to just why Chevrolet didn't make an effort to put the holes at the same level and why wasn't this checking procedure addressed in the Shop Manuals for the LM's? Or maybe a tag included like the EM's?

Bob Helt

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