Automatic Transmission Fluid Typs

This has been bugging me for over thirty one years but here it goes. What is the difference between Dextron & Type F automatic transmission fluids ? When this mystery first surfaced inside my head, it was 1976 & the word "internet" was completely unknown, I was in high school & the library really sucked when it came to automotive technology.

Reply to
Shawn
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dextron has a higher heat range before it gives out. learned that in a bus garage that had hundreds of automatics in the fleet.. since i been useing dextron in old fords with no troubles.lucas

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Reply to
ds549

I'm not sure about the "heat range", but I'm told Type F has slightly different friction characteristics. I worked in a local trans shop for a few years in the mid-80s, and we used Type F for all US made automatic transmissions ( common 3 speed automatics and early ODs then). The shop was highly trusted and had an excellent reputation, unlike many. Our builder told me, in a nutshell, that Type F was formulated to have a bit higher coefficient of friction (not sure if that's the proper term or the one that he used. I's not as "slippery"). It was specified by Ford because the engineers felt Dexron didn't have quite the properties they were looking for. Type F reduced slippage as the bands\clutches were being applied and raised the gripping force on the bands\clutch packs slightly. The difference between the 2 isn't large, though. That is highly simplified, but you get the idea. The difference IS noticeable. I found that older GM transmissions shift a bit firmer with Type F. I seem to recall that most shift kits recommended Type F for non-Ford applications.

The waters muddy a bit these days. Type F became Mercon III, I think. Then there was Mercon IV. Then along came Mercon V which is (semi?) synthetic. GM and Chrysler had their own iterations that may or may not be compatible. Today, you always want to carefully follow the manufacturers recommendations for ATF.

Hope this helps clear things up a bit. Maybe someone can explain the difference in-depth. Regards, Tom

OBTW, The correct name is Dexron. No "T".

Reply to
Tom Adkins

Yet, since the internet came out, you have yet to find the web sites called "Google" and "Yahoo."

Reply to
Jeff

Back when all we had to choose from was Dexron and Type F, the big difference was, indeed the co-efficient of friction.... Dexron gave a "softer feel" to the shift.... It is "slipperier" when the speed of the friction material approaches the speed of the "steel" member....

The base stocks were identical and only the add-pack was different....

Reply to
Jim Warman

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