Greetings, and welcome to TN.

Viscosity, the measure of resistance of flow, at a given temperature. Fluids are 'thicker' when cold, and 'thinner' when hot. For ATF - the base (stock) formulation of the fluid, in conjunction with the additive pack(s): friction modifiers, anti-oxidants, etc: determines the viscosity range, and longevity of the fluid.

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1. Current Valvoline Maxlife ATF is 'thinner' vs. the original Dex III spec., because it was 'designed' that way. It uses a high quality fully synthetic base stock, w/ an excellent friction modifier pack that is very compatible with the Aisin transmission(s) in the Toyota Camry. Because the MaxLife ATF base stock is fully synthetic: it does not 'shear down' (or, lose viscosity - due to mechanical forces) as quickly as a conventional fluid does over time, it's a longer life fluid.

For those living in 'colder' states / winter months, the argument can be made that MaxLife is actually beneficial, due to the lower cSt (viscosity) in colder temps., that it affords better "cold start" lubrication; and affords a small MPG increase, due to the reduced friction of the fluid.

Many use & like the fluid here on TN. It is very affordable: for a full synthetic fluid. (Walmart)

Typical Properties: MaxLife ATF
KV100 (cSt) 5.9
KV40 (cSt) 28
Viscosity Index 163
Specific Gravity @ 60°F 0.844
Pour Point (oC) <-42
Brookfield Viscosity @ -40°C, cP 9,000
ASTM Color 7
Appearance Red
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2. Valvoline Import Multi-Vehicle ATF is the 'thicker' cousin to MaxLife ATF - and closer to the 'original' Dex III spec. of 7.3 cSt @ 100c. Why use a 'thicker' fluid? On an older transmission that has not been maintained, the 'argument' can be made that using a fluid closer to the (original) Dex III spec. may benefit that transmission, if there are wear / clearance issues or concerns. That's the benefit. The cost? Between 1.5 to 2x more expensive, vs. Maxlife ATF.

Typical Properties: Import ATF
KV100 (cSt) 6.9
KV40 (cSt) 36.3
Viscosity Index 153
Specific Gravity @ 60°F 0.849
Pour Point (oC) <-52
Brookfield Viscosity @ -40°C, cP 18,000
Appearance Red
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3. Castrol Transmax Import Multi-Vehicle is also an excellent ATF fluid - used by many TN folks here.

Typical Characteristics
Name Method Units
Transmax Import Multi-Vehicle
Viscosity, Kinematic 100C ASTM D445 mm²/s 7.4
Viscosity, Kinematic 40C ASTM D445 mm²/s 35
Viscosity Index ASTM D2270 None 185
Viscosity, Brookfield @ -40C (75W) ASTM D2983 mPa.s (cP) 17400
Pour Point ASTM D97 °C -38
Flash Point, COC ASTM D92 °C 213
Specific Gravity at 60°F ASTM D1298 - 0.859

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4. Toyota ATF Type T-IV is a full synthetic ATF - specified by Toyota to be fully compatible, with type T-III fluid. Type T-IV spec, see post #13

Edit:
per @JohnGD 's post below - there is a TSB TC003-99 stating T-IV is not compatible w/ T-III fluid spec. - appears to be further reinforced in subsequent "Automatic Transmission Fluid Requirements" TSBs from Toyota: TC-001-02, TSB1095-Change3b.

Best not to use Type T-IV fluid, in the Gen3 - 4.5 series transmissions.


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All of these modern ATF fluids are full synthetic, and will last 2x longer vs. the 'old' Dex/Merc III, all have better additive packs / friction modifiers (good chemistry), and are compatible w/ your Camry.

Which to choose?

Personally, I went with (2.) above for the transmission & differential: and (1.) above for the power steering - only because I did the first service on the '00 Camry here @ 215,000 miles, the transmission fluid that was in there was not maintained like it should have been: and I wanted a replacement fluid closer to the original Dex III spec., to start with.

Why Valvoline? Because I like Valvoline products.

Would Castrol, Toyota, or Mobil have worked also? Absolutely. They are excellent fluids to use also.

 

^ I've used the castrol and Valvoline suggested above.. .good stuff and easily available off the shelf at many stores.


The Toyota stuff, you have to go to a dealer and are limited to their location / hours. if you have time / its convenient then that's fine though.

 

@Nemaris Valvoline Maxlife ATF is basically a fully synthetic Dexron VI. I stayed on the thicker ATF side (such as Mercon-V) for a good while just to see how this thinner fluid worked out. In the end I jumped onto the bandwagon and this fluid is great for Dexron III applications.

Dexron VI is approved by GM to supersede Dexron III anyway.

No, I would not use T-IV which as a lot of friction modifiers in it in Dexron III transmissions. I have NOT read any TSB after TSB TC003-99 stating Toyota reformulated the T-IV for D-III applications. And therefore the following chart still stands AFAIK:

 

Thanks for re-posting that info on T-IV @JohnGD , I updated my post to reflect that info.

Always appreciate your knowledge and contributions / posts to TN, they've helped me out here w/ our Camry.

 

I ran ATF Maxlife for 6 years, then switched it out for Castrol TransMax ATF High Mileage. Which has been behaving much better with it. I use to get slip every once in a while with MaxLife, but not any more. At 235k, its best to use what its recommended in the car, and MaxLife doesn't meet the specs exactly for the Camry. TransMax does.

 

Been using Walmart Super Tech Dexron/Mercron for many years. No issues.