[W126 Coupe] tranny fluid -Heat and Transmission failure

[Richard Hogarth]

FYI -  RPH
Beat The Heat!
Transmission Life Expectancy
There's More To Coolers Than You Think: It's no secret that heat kills
automatic transmissions. And in high-performance street-strip applications,
the problem is especially acute. Small diameter torque converters coupled
with stop-and-go traffic greatly increase the heat level in an automatic
transmission. In most cases, the extra performance heat under the hood can
have the same effect as heavy loads, trailer towing and desert conditions.
How hot is too hot? The ideal operating temperature for automatic
transmission fluid is between 175 and 225° F. At approximately 240° F,
important additives in the ATF begin to cook. The result is the formation of
varnish inside the transmission. At approximately 260° F, internal
transmission seals (which are typically manufactured from a polyacrylate
material) begin to harden. The end results are leaks, both internal and
external, simply because the seals lose their elasticity. At approximately
295° F, transmission clutch plates begin to slip because the oil is breaking
down further. At approximately 315° F, seals and clutches effectively burn
out. Carbon forms in the oil and for all intents and purposes, the
transmission is junk. Just for your information, a typical transmission will
die within 2000 miles if subjected to 300° F+ heat.
 
-RPH
 
 
 
 
 
 
 
 
From: mbcoupes-bounces at mbcoupes.com [mailto:mbcoupes-bounces at mbcoupes.com]
On Behalf Of Mister McGoo
Sent: Thursday, April 05, 2007 11:04 AM
To: Mercedes Coupes Mailing Lists
Subject: Re: [W126 Coupe] tranny fluid
 
Oh?  half a bath?  Look at it this way...  how often do you change your
transmission fluid?  If you're only going to change half of the fluid at a
time by not draining the converter (an exaggeration... you're changing
considerably more than half), then change it twice as often, right?  But
ALWAYS change your filter, OK? 
 
Let's not turn changing your transmission fluid into a religious experience.
We have read how to check the oil level every which way short of while
driving at 50mph.  We have even heard that the dirt in your fluid might
actually be the only thing that is holding your transmission together,
('specially if you drive a Volvo).
 
Advice:  Simply follow the Mercedes instructions.  If you don't do it
yourself, take your car to a Mercedes specialist.  

OK?

-Bellamy
  _____  

From: mbzman560 at hotmail.com
To: mbcoupes at mbcoupes.com
Date: Wed, 4 Apr 2007 21:23:13 -0700
Subject: Re: [W126 Coupe] tranny fluid

Steve- I'd say amen to that.  Not draining the converter is like taking a
1/2 bath, or only draining half of your motor oil.
Camran


 
 
  _____  

Get news, entertainment and everything you care about at Live.com. Check it
out! <http://www.live.com/getstarted.aspx%20> 
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.pairlist.net/pipermail/mbcoupes/attachments/20070405/163a0abd/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 44390 bytes
Desc: not available
Url : <http://www.pairlist.net/pipermail/mbcoupes/attachments/20070405/163a0abd/attachment-0001.jpe>