Same old question: Tranny fluid?

[Ambush]

Okay friends ...merry Christmas first of all to the forum members. But here's my dealio. I need to add some transmission fluid to my 1965 Imperial Crown. It is the original motor ( no rebuilds ) and has 90+ thou mileage to date. From what I've read Dexron III, or Mopar ATF+4 are both good modern equivalents for the AQ-ATF suffix"A" (Type A -suffix A ) fluid the manual calls for. Now this may be a dumb question; but aren't these 2 equivalent fluids synthetics? Wouldn't the original type-A fluid used back in '65 been a conventional type ( minerial oil based or something ) rather than a synthetic? Maybe they were using synthetics back then, but I don't know.

So for an original 413 motor w/ 90+ miles on it ...what would be the best ATF to use? Is there any non-synthetics still out there that would be a good choice in my case ...or are the synthetics okay to use? I'm a bit of a purest w/ these cars - try to stick to the original Chrysler engenneers guidelines where possible. They kinda knew what they were doing

Thanks.

 

[USSMOPAR]

 

[CBODY67]

Dexron III is still "dino", Dexron VI is syn. ATF+4 is part-syn, I believe, but not full-syn?

Chrysler changed its prior Typa A Suffix A fluid to the first Dexron in 1967 or 1968.

Dexron III is now terned "Type III" by ACDelco. On other brands, it is "Multi-Make", but dialogue on the bottle states the primary vehicles it can be used in are GM vehicles prior to the Dexron VI spec.

Not getting in to a "what's the best fluid", just "equivalent fluid" comments.

Considering the Chrysler 3-spd automatics had no lock clutch torque converters back then, any fluid will work. As things have evolved, better additive packages in the normal Dexron fluids have become better than back then. In many respects, anything more can be over-kill for what is actually needed.

Any full-syn or syn-blend fluid can make the existing stuff inside last longer, but if the old fluid has got things this far along, a fresh change to new DexronIII should keep it going quite a bit longer. Just my observations.

IF doing a full rebuild, then you might want to consider going to full-syn DexronVI or similar. That way, any internal seals/bushings will have 100% of their life ahead of them and protecting that with full-syn atf can help them last longer than that.

You can always usually tell if the fluid is dino or full-syn by the price of it. Seeing that difference, normal Dexron III can be just fine. Just change it every 40K miles or so if not trailering anything.

Hope this might help,
Happy Holidays,
CBODY67

 

[RemCharger]

Dex lll

 

[bronze turbine]

You can put just about anything in a TF and it will work, as long as it's compatible with what's already in it. I think what you want is the cheapest universal ATF fluid you can buy at your local service station.

 

[bronze turbine]

But yes, Dexron III, generally speaking.

 

[Ambush]

Never can learn too much on this topic ....great info, thanks guys

 

[Just Carbs]

The synthetics don't burnup as fast. So, you probably won't have to change it if you manage to overheat the car.

 

[cbarge]

Speaking from experience..ATF4 is more expensive and when travelling not all gas stations or truck stops carry it.
I had a 904 rebuilt and used ATF4 in it.
It leaked and drank that synthetic schit.
Yes it gave crisp shifts but the 318 Coronet was no muscle car either
I rebuilt my 68 Newport 727 with a light stall and shift kit and use el cheapo Dexron III. Need a top up? No problem buying it anywhere and no leaks.
So if you are just doing a " service" Dexron III with a bottle of Lucas trans conditioner.
Adjust the bands and yer golden.
Hope this helps.