Gearbox change or rebuild?

[Jezza_hr]

I know that these fluids aren't magic red, but if I can prolong the life of my gearbox until I find one to exchange it over with then I see no reason why not. I'm looking into changing the engine in the not too distant future so it would be an ideal time to do the gearbox too.

[NoHachi]

ATF is just ordinary oil with slightly different specifications. Usually the specs fall within the manufacturers recommended specification range.

[matt mead]

atf is just thinner...... i think it is magic

[EE80Liftback]

NoHachi Wrote:ATF is just ordinary oil with slightly different specifications. Usually the specs fall within the manufacturers recommended specification range.

Sorry for the offtopic:

That is not true! ATF is really made out of something different. In the old days ATF used to be made out of something found in whales (yes, fish) and nowadays I think they're using something they grow on field at a farm...

ATF lubricates much less but is much better for the very tiny hydraulics used for the "thinking" in an automatic gearbox. OK, I guess you could say it's still oil and of course thin oil is better for hydraulics and less good for lubrication but I think that's not fair. It's just not the same. I'll see what I can come up with to support my arguments a bit better, I've got an interesting article about it at my parents place but that doesn't really help me now...

[Red]

EE80 has the point. Viscosity ratings aren't all there is to an oil.

It's an old trick to replace brake fluid with ATF in order to swell up leaking cylinder seals and make the brakes work a while longer.

The magic ingredient in ATF used to be sperm whale oil, which was also considered the finest lubricant for sewing machines and other light gear oil, until sperm whales got a bit expensive to process. The replacement is often jojoba bean oil. Cheaper and safer to hunt, with fewer protests.

And, if "oil is oil" was true...do you guys really think pouring "oil is oil" into a gearbox could HEAL WORN PARTS?? Then the next poor sucker buys the car and wonders wtf the previous owner did to screw it up so badly...

[EE80Liftback]

Here you are: http://www.machinerylubrication.com/arti...t%20Burned

Some quotes from this article:

Quote:The trouble was, thousands of sperm whales were killed every year to acquire the almost 29 million pounds of whale oil used in ATF. Sperm whale oil is an almost pure ester, not really an oil at all. So the Endangered Species Act of 1973 was brought about partly by automatic transmissions.

Quote:Spanish explorer Hernando Cortez was introduced to a medicinal skin oil and lubricant that the Aztecs used called Jojoba. It is almost the chemical duplicate of spermaceti, the oil from the head of the sperm whale. Both are esters, not (hydrocarbon) oils. Esters occur when an acid is reacted with an alcohol. Esters have strong atomic bonds and do not oxidize easily, They do however handle heat well.

[NoHachi]

Check out the specs on a bottle, there is more to it then just visco ratings.
Esters are used in ordinary oils too.