SodaLuvr

Four years ago, Amsoil Universal ATF was a fluid recommended for use in Dexron III, Mercon V, and ATF+4 applications by Amsoil. That was in late 2002 or early 2003. (Don’t recall exact years, irrelevant anyways)

In 2003, Amsoil began recommending their fluid for usage in Honda ATF-Z1 and Toyota T-IV applications upon the completion of their field and bench testing. However, no reformulation of the product needed to taken place in order for the Amsoil Universal ATF to be used successfully Honda ATF-Z1 and Toyota T-IV specifications.

While I personally know of many satisfied users of Amsoil Universal ATF in Honda ATF-Z1 and Toyota T-IV applications, this contradicts and raises doubts regarding the different dynamic friction properties between automatic transmission fluid specifications.

My understanding of these dynamic friction properties of automatic transmission fluids, based upon my discussions with industry experts, is that the dynamic friction properties between automatic transmission fluid performance standards may vary significantly. In addition, only a slight difference in the dynamic friction properties of a fluid is needed to cause slippage or harsh shifts.

While an end user may be satisfied with the product provided that the fluid allows for proper operation of their automatic transmission, it still poses questions with regards to the true compatibility of these fluids in applications that it was not originally designed for.

In addition, I’ve been told by various people that certain proprietary fluids such as the ATF+4, Honda ATF-Z1, etc contain a higher level of friction modification compared to Dexron or Mercon fluids. Thus, was Amsoil able to successfully complete the testing of, and begin recommending their Universal ATF product for use in Honda ATF-Z1 and Toyota T-IV applications solely because the level of friction modification already contained in the fluid allowed it to perform successfully in applications other than it was originally designed for (i.e. Honda ATF-Z1 and Toyota T-IV), and the fluids are truly compatible for the Honda and Toyota applications? Or, was the fluid just “happen to work” in Honda ATF-Z1 and Toyota T-IV applications?

Thanks.

1killercls

Put that in your trans and kiss your 100k warranty goodbye.

SodaLuvr

Solely installing a different automatic transmission fluid than the one recommended by the manufacturer is not enough for the manufacturer to deny a warranty claim. The burden of proof is on the manufacturer to prove the fluid's contribution to the failure, at that point, if the fluid was found to cause a problem, the fluid manufacturer is liable.

1killercls

Knowing how car Companies work...see you in court.

SodaLuvr

As they say, its better to avoid a fight than to win one later...

With that said, if your transmission is going to fail tomorrow, then common sense will tell you not to install it. However, there have been a few members of this forum who have used a non Honda ATF and were not even questioned when their transmission failed.

1killercls

Link???

NSXNEXT

iTrader: (2)

The transmission failing has less to do with fluid type and more to do with fluid circulation. The 3rd gear clutch pack failure is a result of not enough tranny fluid getting to that clutch pack to cool it down.

I continue to use the Honda Z1 fluid in my car (soon to turn 100K on the original tranny) My 4-speed 99TL however does not have as significant an issue as the 5-speeds.