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What synthetic ATF fluid/oil is better than WS.

115K views 57 replies 18 participants last post by  Foryota 
#1 ·
Hi just wanted to know if to upgrade my fluid from the Toyota WS as it is not synthetic, or is it best to use Toyota WS.I like Castrol synthetic fluid.
Please let me know your opinion and any advice would be greatly appreciated.
P.S
Info:
Van has 48000 miles.
First ATF fluid change, I am doing a full machine flush.
I use Castrol Edge synthetic in engine.​

Thanks:smile
 
#2 ·
Toyota does not recommend a machine flush for WS fluid equipped transmissions in spite of what the dealer/garage says. The chance for overfill or underfill is great and they are VERY sensitive to the amount of fluid in the trans. The person using the machine must be an absolute expert in its use and follow Toyota procedures exactly. Few have such a person on staff.

I got this information from a top ASE certified Toyota/Lexus mechanic in Austin, TX. He is one that is qualified but has seen too many failures from this procedure and refuses to do it. His recommendation is to drain & fill three times over a short interval and use nothing but WS fluid NOT an equivalent. Were it my vehicle I would not chance it.

Having said that there are several folks here who have used other than WS fluid without problems......so far. If damage is done it will be over the long term.
 
#3 · (Edited by Moderator)
Which Transmission Fluid Do You Prefer.

I'm gonna be flushing the transmission and just wanted to get some testimonials from people. There are alot of debates on which fluid to use. I know some poeple say Toyota WS but I am leaning toward a Full Synthetic ATF.
Valvoline Max Life ATF
Valvoline Dex/Merc
CASTROL TRANSMAX Z
Castrol Transmax Dex/Merc
Castrol Transmax Import Multi-Vehicle
Mobil 1 Synthetic ATF
Redline ATF
Royal Purple ATF
Amsoil Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid

Or any others.
I'd like to hear your thoughts so send them my way thanks.:smile
 
#6 ·
I'm gonna be flushing the transmission and just wanted to get some testimonials from people. There are alot of debates on which fluid to use. I know some poeple say Toyota WS but I am leaning toward a Full Synthetic ATF.
Valvoline Max Life ATF
Valvoline Dex/Merc
CASTROL TRANSMAX Z
Castrol Transmax Dex/Merc
Castrol Transmax Import Multi-Vehicle
Mobil 1 Synthetic ATF
Redline ATF
Royal Purple ATF
Amsoil Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid

Or any others.
I'd like to hear your thoughts so send them my way thanks.:smile
You need to do more reaserch. Not all of those fluids are considered WS replacement.
 
#5 ·
Toyota WS as it is not synthetic
Who told you so?

Also, define better.
Toyota did extensive studies and showed that the low viscosity, fuel efficient WS fluid didn't compromise wear protection in their trannies. Published in the SAE literature.
If you use alternative fluids, you just throw that science away and hope for the best.

I agree flush is not the way to go. Flushes don't clean filters inside.

One more thing, currently, cars are designed with useful life of 150,000 miles. WS is lifetime in that sense. I agree 50,000-60,000 miles is a sweat spot for a change (if no severe service) if one wants to keep the car for a long time.
 
#8 ·
Using Valvoline Maxlife ATF with LGR. First two drain and fills were with just the ATF the next two had LGR added. No issues and no crud on the drain magnet. Planning on running Amsoil SS ATF when I do a pan drop to change out the filter. I'll definitely be looking forward to seeing what the magnets and inner pan walls look like.
 
#10 ·
#12 ·
@ the OP:

While Valvoline claims MaxLife is "suitable for use in" WS applications, it also has this disclaimer on the PDS:

"Valvoline has conducted extensive in-house testing, independent lab testing, and field-testing to support MaxLife ATF performance in the broadest range of transmissions; however, it should be noted that MaxLife ATF is not a OEM licensed product. The respective vehicle manufacturers have neither evaluated nor endorsed MaxLife ATF in these applications."

Caveat emptor.
 
#14 ·
#16 ·
Is WS a fully synthetic product? If it's not, then I think it's fairly safe to say better ATF's are available.

I found this thread that's quite interesting:

Interesting Toyota WS ATF Research. | ATF, Differential, Trans, Brakes, P/S | Bob Is The Oil Guy
Maybe that was interesting way back in 2008 when we knew little about it.

Here is a newer BITOG thread on it:
Toyota WS | ATF, Differential, Trans, Brakes, P/S | Bob Is The Oil Guy

I'm surprised you missed it in your search.
 
#15 ·
One thing to remember: having a synthetic base does not necessarily mean a "better" product. You have to consider whether the additive pack is correct for the application.

Chrysler ATF+4 is synthetic, but would be all wrong for a RAV, and just because a blender claims their product is "suitable for", doesn't make it so.

Using the OEM fluid, or an aftermarket fluid that is licensed by or approved by the manufacturer, guarantees it's suitable for the use and when changed at intervals appropriate for the vehicle's use will give excellent service.
 
#18 ·
This is what I wrote in my BITOG reply (the one you didn't like):

Originally Posted By: 147_Grain
So can anyone confirm that WS is Group III?



I don't think anyone can. These things are trade secrets. The best documentation on WS is from Toyota as published in the SEA paper here:
SAE汽车�动机英文论文2003年全辑之 (2920) - 豆�网

They hint about base oil being group 3 or 4 (page 2).
As for that shame on toyota part, show me how anyone in the car or lubrication industry tells you exactly what they put in the bottles called motor or tranny oils.
 
#19 ·
As for that shame on toyota part, show me how anyone in the car or lubrication industry tells you exactly what they put in the bottles called motor or tranny oils.
Toyota doesn't seem to license compatible products like GM does with DexOS approved oils and ATF.

I'm not asking for Toyota or other companies to tell me what's in their products. Only to tell me what's required when it comes to meeting their specifications.

Maybe Toyota kills whales and puts that in the automatic transmission fluid and that's why it's so special.

>:D
 
#21 ·
two notes on ATF flush. First, I tried regular ATF dexron fluid for a few months to see what happened. As the fluid is thicker, performance really dropped. I did this at 100K miles, and the fluid was brown and ugly.

Second, I went to Valvoline Maxlife ATF based on my research, and performance came back up. HOWEVER, with the standard drain and fill method, you are changing 3 qts of an 11 qt. system. So the fluid is still crap ... LESS crap, but still crap.

I did a mathematical calculation (Excel) and showed that changing it multiple times makes the contamination concentration be less and less. Specifically, if you assume that at it's max life, the percentage of contamination is 100%, changing only 3 qts means that it's then 72.7% contaminated ... so you change 3 qts again and it's 52.9% contaminated .. another 3 qts and it's 38.5% ... then 28.0% ... then 20.3% ... then 14.8%. So I decided to change those 3 qts every week for 6 weeks to get the contamination down to 15% ... then every time I change the oil, I drain and fill 3 qts. and the fluid is always clean. That was 50K miles ago and it stays clean.

Use MaxLife or don't ... don't care ... what I want the message to be is to realize that changing your ATF is doing almost NOTHING because you're only changing 3 of the 11 qts in the system ... all your doing is REDUCING the contamination ... so you need to reduce it multiple times to get it clean (a relative statement ;-). Or, of course, do a dealer authorized flush where they are supposed to get all the fluid from the torque converter and such.
 
#23 ·
No doubt that pulling that line and running the engine to get it all wastes less ... but my way means you don't have to lift the car, remove the trany bolts and cover, maybe change the filter, re-attach the return line, re-torque the bolts, worry about a leak, etc. Again, don't care about the fluid, or for that matter, how you do it ... the bottom line is for people to realize that just dropping 3 qts is NOT changing your ATF ... there's still 8 qts inside there so it's still plenty dirty.
 
#26 ·
So this is probably a stupid question but what does WS stand for?

Also, Amsoil states that the transmission fluid is 6.4 quarts. What is the official capacity for the V6 4WD models?

Finally, would you recommend taking the vehicle to the dealership for diff, transfer case and transmission fluid change compared to doing it yourself or taking it to an independent shop?

Just so we are on the same page: I've been wrenching, tuning and racing cars for over 15 years now so I am quite handy. I have a full garage with pretty much everything except a car lift. However, this is my first automatic and my first 4WD system I am dealing with.
 
#27 ·
WS stands for World Standard. Based on my research, I use Valvoline MaxLife ... but that's not saying Amsoil won't work.

I have no idea what capacity yours is ... suggest you use a web site like https://carmanuals2.com and look it up.

assuming you don't have any pumping tools to get the fluid out from above, you need to drop the plastic cover from the bottom of the engine to expose the plug ... I think any handyman can do it.
 
#28 ·
Thank you for clarify on the WS acronym. Makes perfect sense now.

Concerning the pumping tools.... Well, looking at the DIY instruction guides out there, everyone seems to be doing the drain, run engine, refill method multiple times. That seems quite inaccurate and also suggests that the transmission pan is not the lowest point of the system or it is not the only low point in the system where fluid collects. So pumping tools won't be of much help unless you can reach every low collection point in the system.

Thank you for the link! The manual states 9.3 quarts for the transmission fluid and 0.5 quarts for the transfer case.

Now I need to hunt down filters and fluids.
 
#29 ·
I have read upwards of 16 quarts. You are forgetting the torque converter acting like a gigantic reservoir.

All my cars since I was 16 have all been manuals , so I too once felt lost when it came to ATs. But having done a few (father's, wife's), I am more comfortable. Most require you to drop the entire pan. Ours at least has a nice drain plug. This will be the first time for me doing the RAV. Surprised someone with so much garage time would recommend others do this job at the DEALER.

I have some MAx life on hand. But I am going with Amsoil OE FE.
 
#30 ·
I am confused. I am not recommending that others go to a dealer. I am asking if I should take my car to a dealer to get this done?

Honestly, the cost of the parts is a "chump change" compared to my BMW. I am at 60K miles as a second owner, and I plan on towing my BMW. So I am thinking it is a good thing to change the transmission fluid and transfer case fluid pre-preemptively.
 
#34 ·
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