Re: quattro-digest V3 #1320

["Al Powell" <APOWELL@agcom.tamu.edu>]

> From: Glenn Kaufman <gkaufman@ftp.com>
> 
> Does anyone have any opinions and objective data on synthetic transmission
> oils?  This weekend I'd like to change the oil in my transaxle in my 86
> Coupe GT.  Last summer, I added Penzoil's dino transmission oil.  Since the
> weather has been getting colder, the trans takes awhile to warm up.
> 
> I've been happy using Vavoline's semi-synthetic motor oil and am considering
> putting in their full synthetic tranmission oil (GL4).

Strongly suggest you do just that.  Transmission oil goes a LONG time 
between changes.  The synthetic will resist polymre chain breakdown 
better, tolerate high temps better, and dissipate heat more 
efficiently.  My local tranny guy sez it's the only thing he 
recommends in automatics for the Audi turbos.  I agree!!  It's in my 
200.  (Amsoil fully synthetic ATF...)
  
> One interesting note, last time I was at Valvoline, I was told that GL5 is
> just the newer version of GL4.  I believe that one of our members pointed
> out that the difference is in the amount of zinc?  or another metal within
> the oil.  Can someone remind me of the difference?

Can't tell you the specific component which is different - but GL-4 
is slightly less slippery than GL-5.  In some cars (Like my 280 ZX) 
the tranny will not shift as well with GL-5 because it's to low 
friction for the synchros to grab.   In other cars, it may not 
matter.  Myself, if it sez GL-4, I'll use Gl-4.


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Al Powell                        Voice:  409/845-2807
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"Some people can tell what time it is by looking at the
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             [From 5th/6th grade essays....]