Trying a Different Fluid Viscosity/Formulation

Shel_B

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I'm running Toyota's WS fluid in the Camry. As far as I know, the car has had but one fluid exchange, back around February of last year. The exchange was done at around 80,000 miles.

Since the transmission has a fair amount of miles on it, I was thinking about wear, and I realized that I know even less about xmission fluid than I do about oil. So, a few questions:

Is it reasonable to use a more viscous fluid as the xmission ages, perhaps akin to going up a grade with high mileage engines? Might the heavier fluid affect mileage?

Should I decide to go to a heavier fluid, I'd probably choose something like Aisin WS, or Idemitsu WS (sp?) that are presumably closer to the Toyota spec (I would verify that through tables and comparisons that I have here). Would mixing a different formulation with the Toyota WS cause any issues? My thought was to add fresh fluid with a drain and fill rather than a full exchange, thereby giving something approximating a 50/50 mixture of the fluids.

Thanks!
 
I think you are asking for trouble. Stick with the manufacturer recommendations.
Sounds like he's asking if it's OK to use other brands of WS fluid in with the existing WS fluid that's in the transmission, Aisin WS or Idemitsu TLS-LV (WS) should be fine.
 
and I realized that I know even less about xmission fluid than I do about oil
Hmmm....
Is it reasonable to use a more viscous fluid as the xmission ages, perhaps akin to going up a grade with high mileage engines?
No
Would mixing a different formulation with the Toyota WS cause any issues?
No one can answer that question. It would be 100% hypothetical if someone bothered.
 
Anything rated WS should be fine, even if the viscosity is not an exact match to what's in the Toyota bottle. Part of the WS spec is low viscosity, if I'm not mistaken. Since you did a full exchange recently, periodic drain and fills will be an easy way to keep the fluid fresh. (I'm assuming your 2010 has a traditional drain plug and dipstick.)

I used WS in a 2010 Vibe (Toyota U341E trans) for awhile and then switched over to Maxlife with no problems until the car was totaled. An "actual" WS fluid would be a closer match than Maxlife.

Vibe WS and Maxlife UOAs
 
I am willing to bet there are more Toyotas, especially those that are outta warranty, that are running around on MaxLife than Toyletta WS, by far.
I use MaxLife or Idemitsu WS equivalent in the Toyotas I service.

Toyota WS is nothing special, not even synthetic.
 
I replaced WS with a normal viscosity import ATF. I figured it would shear down enough not to be a problem. Being full synthetic, even a 7cst ATF should have no problem with the cool weather, when compared to a ~6cst ATF. The transmission functioned perfectly on the thicker full synthetic ATF.

Any like WS fluids aren't a thicker ATF. They are in the range for the LV requirement. Formulations wouldn't make a difference and are mixable.

At this point, you should drop the AT pan, verify the magnets are clean, upgrade to 4 magnets if the pan doesn't have it already, replace the filter, button it up, and refill to the correct level per the service manual. If you are using an LV ATF, WS, or WS equivalent, the viscosity isn't different.
If you replace the filter/gasket, I only recommend the dealer sourced parts. Seen too many issues with fit/finish on non-OE ATF filter parts.
 
I'm very satisfied with the performance of Idemitsu TLS-LV in my recently acquired Toyota Yaris. I also cleaned out plenty of grey sludge from the transmission pan before bolting it back on with a new wix atf filter. Its the same viscosity as Toyota WS cst @100c 5.3. Valvoline Maxlife atf is slightly thicker at 5.9 viscosity and should work well also.
 
I am willing to bet there are more Toyotas, especially those that are outta warranty, that are running around on MaxLife than Toyletta WS, by far.
I use MaxLife or Idemitsu WS equivalent in the Toyotas I service.

Toyota WS is nothing special, not even synthetic.
I'd take that bet and say there are more Toyotas, especially those outta warranty, that are running around on the factory fill.
 
I'd take that bet and say there are more Toyotas, especially those outta warranty, that are running around on the factory fill.
In general, Toyota transmissions are exceptionally reliable, even without any fluid changes. For the average first owner, I really don't think there's a ROI to replacing the fluid.
 
[QUOTE="Rhymingmechanic, (I'm assuming your 2010 has a traditional drain plug and dipstick.)
[/QUOTE]

It's a 2011, and it doesn't have those features.
 
I am willing to bet there are more Toyotas, especially those that are outta warranty, that are running around on MaxLife than Toyletta WS, by far.
I use MaxLife or Idemitsu WS equivalent in the Toyotas I service.

Toyota WS is nothing special, not even synthetic.
I'm using MaxLife in 12 RAV4 with 53k. So far nice n smooth.
 
I am willing to bet there are more Toyotas, especially those that are outta warranty, that are running around on MaxLife than Toyletta WS, by far.
You're referring to Toyota-owning members here, right, not the general public ?
 
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