Transmission Oil

[Tom Sahines <tsahines@domain.elided>]

I want to thank all of you who use synthetic oils in your trannys. It keeps
my transmission rebuilding service VERY active. While there have been many
posts discussing the pros and cons I can tell you from personal experience
that the use of synthetic oil in a transmission is the primary cause of
failure that I see. It comes in a strange way, loss of all fluid. Seems
that the synthetic oil just does not want to stay in these trannys. Also
causes premature failure of the syncros.

I keep reading about how it is great in my BMW or other modern car. Well in
fact it may be! But remember that the Alfa transmission is not a modern
transmission! In fact all of the transmissions including the transaxle cars
are using the same design which first appeared in 1962. No change has been
made to the transmissions to keep up with more modern materials or designs.
The properties of the oil used make a huge difference in the performance of
the transmission. The correct oil provides for the proper frictional
characteristics between the syncro and slider. Modern high tech oils are
just to slippery.

So what is the answer. Well the factory recommended a fluid. Seems like
that might be a good place to start. Spirax (Shell oil) is the correct
fluid to run in your transmission. It provides the correct lubricity for
proper syncro operation and is currently rated for GL5 service so it works
fine in the rear axle.

When I take apart a transmission that has been faithfully run on Spirax I
have seen no wear on the bearing surfaces and only moderate wear to the
syncros and sliders. These trannys can be rebuilt with minimal effort to
produce new quality performance. 

You do not need to change the oil often. Every couple of years will do. But
check the oil level at least every 6 months. More often if you have a leak.
Remember that loss of oil will make the tranny essentially worthless for a
rebuild, since it is cheaper to buy a good core to rebuild than it is to
change all the bearings in a no oil burned up transmission.

If you decide to switch back to Spirax after reading this post I caution
you that the transition will not occur immediately. It takes quite a while
for the Spirax to displace the synthetic or other transmission oil. Usually
about 500 miles, longer if you drive only short distances. After that you
should drain the mixed oils and refill with the Spirax to be sure that all
of the other oil has been removed.

Alfa tranny shift best when you make a slight pause in neutral before
shifting to the next gear. If you want to slam that tranny from one gear to
the next then get your gears lightened. 


TOM SAHINES ARA TECH HOT LINE SAN JOSE CA

--
to be removed from alfa, see /bin/digest-subs.cgi
or email "unsubscribe alfa" to majordomo@domain.elided