Type F fluid recommended by trans builder

[Ken2]

ATF does not contain detergents. ATF doesn't have to deal with blowby the way motor oil does. ATF does contain dispersants to keep clutch particles in suspension.
http://www.lubrizol.com/DrivelineAdditives/AutomaticTransmissionFluidAdditives/default.html

The friction modifier characteristics of the fluid must be matched to the friction characteristics of the clutch material. The transmission rebuilder may select non-stock clutch materials that could work best with non-stock fluid.

It is easy to find real Dexron-III fluid. Look for its new name, Allison TES-389.
https://fdlrd.swri.org/Allison/ApprovedFluidsList.aspx?Id=2

 

[SS1970chrysler]

When I rebuilt the TH350 in my '73 Lesabre years ago, I had choice of kits that either used Dex II/III or Type-F. I'd imagine there might still be similar offerings available today.

 

[Shannow]

Mobil 424 is Dexron...and thick...and stuff.

 

[widman]

They use type F for the firm grip that makes it feel like a performance build.

I would not put type F in anything not originally designed for it. Somewhere I should have some old Chevron studies on how much faster it tears up the discs of transmissions designed for Dexron or Mercon.

There are a lot of myths in statements above.

 

[mechtech2]

widman -
You have it backwards.
Type F makes the discs and clutches last longer, not shorter!
That is a major benefit.
Modern trannys with electronics and lock ups are a separate issue.

 

[widman]

Originally Posted By: mechtech2
widman -
You have it backwards.
Type F makes the discs and clutches last longer, not shorter!
That is a major benefit.
Modern trannys with electronics and lock ups are a separate issue.


Wrong. Tears them from hard contact. Just like popping the clutch on a manual transmission.

 

[SteveSRT8]

Originally Posted By: widman
They use type F for the firm grip that makes it feel like a performance build.

I would not put type F in anything not originally designed for it. Somewhere I should have some old Chevron studies on how much faster it tears up the discs of transmissions designed for Dexron or Mercon.

There are a lot of myths in statements above.


Absolutely agreed.

Many here think that a firmer shift equates to longer life. This is sometimes true in a very slow shifting slushbox that has lower pressures. This generates a ton of heat as well.

As I said in my post earlier: NOT RECOMMENDED for the street!

 

[partspro]

The question REALLY is what parts are the trans builders using in the rebuild. I used to work with a guy who owned a trans shop and was extremely knowledable on trannies. Brass clutch backs needed type F for sure. Its all about Friction Modifiers. Paper clutches can be torn up pretty quickly by Type F but smoother shifts wiull be the norm until then.

 

[mechtech2]

Originally Posted By: widman
Originally Posted By: mechtech2
widman -
You have it backwards.
Type F makes the discs and clutches last longer, not shorter!
That is a major benefit.
Modern trannys with electronics and lock ups are a separate issue.


Wrong. Tears them from hard contact. Just like popping the clutch on a manual transmission.


Slipping is when wear occurs, not when engaged - there is no wear when engaged. And there is NOT an on/off condition with type F, just a faster engagement.
Remember, guys used type F to FIX wear problems. Our theories won't overcome the fact that it worked rather well for this.
There are no myths about this.
The only time that I have seen pieces [not dust] of clutch material in an auto tranny is when the friction material was worn down to the metal, and it could come off here and there.

 

[crazyoildude]

i use type f in my 1992 saab 2.0 turbo convertible with the three speed automatic transmission, always have with no problems

 

[widman]

Originally Posted By: mechtech2
Originally Posted By: widman
Originally Posted By: mechtech2
widman -
You have it backwards.
Type F makes the discs and clutches last longer, not shorter!
That is a major benefit.
Modern trannys with electronics and lock ups are a separate issue.


Wrong. Tears them from hard contact. Just like popping the clutch on a manual transmission.


Slipping is when wear occurs, not when engaged - there is no wear when engaged. And there is NOT an on/off condition with type F, just a faster engagement.
Remember, guys used type F to FIX wear problems. Our theories won't overcome the fact that it worked rather well for this.
There are no myths about this.
The only time that I have seen pieces [not dust] of clutch material in an auto tranny is when the friction material was worn down to the metal, and it could come off here and there.


No point continuing to beat the dead horse. the facts are out there. I suggest those thinking about using type F do their own research. Plenty has been written on the subject.

 

[mechtech2]

OK, let's negate history and experience with type F.
Anything goes!

 

[RF Overlord]

Just to add fuel to the fire, the rebuilder of the TH400 I put in my '68 Buick Gran Sport recommended Type-F and I've been using it ever since. That was in 1979 and it still shifts strong and quick.

 

[artificialist]

Originally Posted By: crazyoildude
i use type f in my 1992 saab 2.0 turbo convertible with the three speed automatic transmission, always have with no problems

Yes, however, the 1992 SAAB 900 specified Type F in the manual.

This involves someone putting Type F in a car that asks for something other than Type F.

 

[yarddogbbq]

use what the rebuilder recommends to protect warranty.