Originally Posted By: keith
Will ATF+4 work in place of Dex3? Who can answer that? I don't believe there is a definitive answer.
No, there IS a definitive answer for that (at least for Chrysler transmissions that formerly required Dex III). And it is YES. Nothing in +4 adversely affects any component of, say, a 1980 A-998 or a 1969 A-727, or a 1992 A-518. ATF+4 friction modifiers are for TC clutch characteristics, and nothing had to be changed in the other clutches or in the band materials to be compatible with it. Chrysler even flatly says that its OK for the Aisin-Warner AW4 in Cherokees. But given that Dex VI should also work in all of those I named and is a more degradation-resistant fluid, that's probably what I'll use the next time my two A727s and my AW4 need a change (actually the AW4 already does need a change...)
Given all that, its quite likely that GM transmissions that called for DexIII will also tolerate ATF+4... but why on earth would GM (or anyone?) advertise that fact or test for it? There's no reason to do so.
I do recall that there is an exception or three somewhere on Chrysler's list of transmissions originally calling for DexIII or ATF+3 that are compatible with ATF+4, but its a real oddball. Maybe the Benz gearbox in the Crossfire, or one of the 1980s Mitsubishi re-badges? I forget, it was one that will never matter to me.
Will ATF+4 work in place of Dex3? Who can answer that? I don't believe there is a definitive answer.
No, there IS a definitive answer for that (at least for Chrysler transmissions that formerly required Dex III). And it is YES. Nothing in +4 adversely affects any component of, say, a 1980 A-998 or a 1969 A-727, or a 1992 A-518. ATF+4 friction modifiers are for TC clutch characteristics, and nothing had to be changed in the other clutches or in the band materials to be compatible with it. Chrysler even flatly says that its OK for the Aisin-Warner AW4 in Cherokees. But given that Dex VI should also work in all of those I named and is a more degradation-resistant fluid, that's probably what I'll use the next time my two A727s and my AW4 need a change (actually the AW4 already does need a change...)
Given all that, its quite likely that GM transmissions that called for DexIII will also tolerate ATF+4... but why on earth would GM (or anyone?) advertise that fact or test for it? There's no reason to do so.
I do recall that there is an exception or three somewhere on Chrysler's list of transmissions originally calling for DexIII or ATF+3 that are compatible with ATF+4, but its a real oddball. Maybe the Benz gearbox in the Crossfire, or one of the 1980s Mitsubishi re-badges? I forget, it was one that will never matter to me.