using additive to the trans fluid

Pretty much the same difference. I use the term potting compound because I believe the stator windings are fully encased and it is not just a surface coating that 'conformal' suggests. One Toyota paper on the NHW10 and NHW11 differences reported they eliminated the seal between the MGs and transaxle gears because they were able to solve the problem of oil in contact with the stator sealing compound.

Excellent practice! Experimenting with data is always better. One signature of micro dieseling is an accumulation of combustion products and an acid increase is one such signature.

This is one of those cases where I'd like to have a sample in solution.

It was a calculated and informed risk that I could assume. But oil testing was always part of my plan and I see it is part of yours. We pays our money and takes our chances. Still, it is worthwhile to bring up the risk factors even if we have to take chances. Experimentation is how we learn.

BTW, the Toyota paper on the NHW11 and NHW20 differences says they replaced the bushings in the NHW20 with bearings. But the key is we are also becoming chemists when we change the lubricant ... not a bad thing but something we approach with our eyes open.

One of the things I did was a cold temperature, hill rolling test. We had temperatures down to freezing earlier this week and even reducing the starting altitude failed to come to a stop before the end.

Between the Type WS I'm currently testing and larger diameter, 51 psi, low rolling resistance tires and near perfect wheel alignment, my rolling resistance has reached a point that my neighborhood 'hill' is too steep to have the car come to a stop on the level part. I'll try again when we get some sub-freezing temperatures.

Three years ago, the hill rolling test showed a significant improvement of new Amsoil ATF over used, 53,000 mile, Texas usage, Type T-IV.

Not yet since I'm already doing a Type WS test. Also, I'm not terribly interested in going to a higher viscosity transaxle oil.

Interesting.

It wasn't meant as a statistical study since obviously, we don't have ready access to the Toyota repair data. Rather, just sharing some of the data.

I don't think so because it had a strong paraffin smell and was opaque. The oil test results continue to show it as one of the worst along with Jessie's 320k mile sample.

This is similar to the partial discharge hypothesis we've been looking at over in Prius Technical Stuff. The voltage generated at an inductor is:

L * (dI/dt)
​

It isn't so bad when the voltage is applied but when the IBGT turns off, the resulting voltage spike is impressive. Some Japanese researchers have found evidence of GHz waves in the motor noise, a signature of a corona discharge. Their research is compelling but they had massive train motors and generators as their test articles in a lab where they could over stress the test article. Transfering their insights into a field test is not a trivial problem.

All data and research needs to be considered.

I've been collecting oil samples for testing. My recommendations are:

• 5-10,000 mile early change - this flushes the initial silicon leaching and wear material
• NHW20 - looks to be good for 60k miles in ordinary usage, more frequent in dusty, rural areas
• NHW11 - looks to be good for 30k miles in ordinary usage, more frequent in dusty, rural areas.
• Use oil testing results on second change to adjust interval for subsequent changes
• NHW11 - has a 15% carry forward of the previous oil. If the oil looks really bad, consider the first change as a flush and change again in 1-5,000 miles.

Experiments are good, especially when backed up with analytical data.

GOOD LUCK!
Bob Wilson

 

I agree with Sparky. I had mine changed around 77K miles. The dealer actually recommended that I not change it until the recommended interval. After insisting that they perform the fluid change, my car has 102 thousand miles. Runs great.

To think that I might somehow know more about my GEN 2 Prius than a laboratory-full of Japanese engineers in white lab coats and black frame glasses is a laugh to me. The only non Toyota fluid in my 2005 is Mobil-One 5-30W. Since they offer this at the dealer, I figure I am safe using it. When my dealer starts offering Red-whine or Scamz-oil (wink-wink) as part of their recommended services, then I will consider it. Until then, the guys in lab coats win. Just my two yen...In my opinion.

How about this for a comparison,- let's say I am pretty good at cooking Mexican food - then one day I start telling the Japanese Sushi Chefs how to make their stuff better. Just add some Jalapen-yo and habanero to the Wasabi and add a splash of Olestra, and you will runnn smoother and not sputter and shutter while spray painting the bowl.... Homey don't think so!
All other gastric anomalies aside, pay no attention to the combustion products and acid increases.
:focus:

I learn alot from this site, and I enjoy the reading too, but my 2005 GEN2 is NO-MOD STOCK. Good enough for the freeways of Kelly-phone-ya.

I digress now to the experts and the topic at hand.

 

No transmission fluid of any kind is going to hurt the insulation on the windings. I designed electric motors for 10 years and I have actually done some research on the subject. I had several applications where the motors would get exposed to hydraulic fluid (every transmission fluid is hydraulic fluid) on a continuous basis and I was never able to find any issues with the compatibility of the insulation and conformal coatings on the windings and any kind of hydraulic fluid. Some motors (including the motors in the Prius) even use it for cooling.

 

All due respect, but my feeble brain wants to know if your research included Motor-Generators - and not just motors.

I admit to knowing less about designing motors as compared to cooking good Mexican food.

 

Are you offering Ed a warranty ? :_>

 

In theory I agree with you on this. However, unless you know the Toyota white lab coat guys personally and have a good enough relationship with them individually that you can trust that they are sharing inside information with you, in the real world there are complications.

A corporation must find a balance between reducing cost to the point of creating a product with a reputation of low quality and increasing quality to the point of drastically reducing the market potential of the product. This balance will create a situation where in some instances, the best possible design is not the design that is chosen. This leaves room for improvement for those who wish to spend the extra money, while creating an affordable usable product for a large market.

On the other end of the spectrum, corporations are profit driven. It is possible for a corporation to gain additional profit when customers have a fear of using quality reliable products from another vendor. This can lead to management and marketing departments making statements encouraging their customers to "only use the stuff that we say to use". While talking to a trustworthy and reliable lab coat, you might find they say that the corporate position on the matter doesn't match their own personal understanding of the facts.

I guess it comes down to your personal opinion about the reputation for integrity, quality, and reliability of the corporation. Fortunately, in my opinion, Toyota has a pretty good reputation on all three counts.

 

Thank you thank you. That's exactly what I said a year ago when I installed the new fluid. Like you I have a strong background in motors mostly field repair & replacement of large 3 phase industrial motors. Saw how they failed. As you know conformal coating failure is rare! Windings fail from excessive load or low volt/under power under load. Bad switch gear etc. Even then winding blowout was rare. As you know thats just not a point of failure no matter what its exposed too. Winding coatings haven't changed much since the 50's. With good reason....its freakin' bulletproof.
Got out of that 25 years ago (too physical and damn dirty!) and moved into Broadcast Engineering a long long time ago. Point is like you I am well aware of whats going on in this transmission electrically.
Anyway everyone said the same thing there all saying now. There's 500 volts in there!!! Death!
Yeah so what. You'd have to take a hammer & chisel to that winding coating.
Its ridiculous to even discuss it.
Toyota knows that and hasn't spent a minute worrying about it. I wouldn't either.
You could run 3 in 1 oil in this transmission and it would be quite happy.
Thanks again for the lone voice of reason.
BTW, loved your rebuild series. That was excellent!

 

Won't need a warranty from Mr Jelloslug as I take excellent care of my car. It runs unbelievable. Better than new.

 

Go for it. I look forward to hearing if it improves the transmision. Just about all high performance products come from racers.
Please post the particulars of this product. Linky please. There's some cool stuff out there for sure. Just remember its a GL-4 product.

 

Well, I'm going to weigh in as I did in the transmission fluid thread. I just replaced my HSD fluid with Redline D-6 after 36K miles (one year). I would swear, though it may be coincidence, that my mpg actually went up by 1 - 2 mpg. I drive the same route every day and have a very good feel about where I gain and lose MPG. Even if there is no change, I also suspect Toyota WS is good but not formula unique and I have had steller results with Redline products in the race cars and other personal cars. I'm trusting it here also. We'll see what happens. I'll post my oil analysis data for both the old and new and contribute to the knowledge of the community as I can. I don't recommend this to anyone else as I don't have any proof it will be OK.

 

Thanks, Steve for your msg and your plans to post your used fluid results. As you and Ed are early adapters of Redline D-6 ATF fluid with respect to the 2G transaxle, I'll be looking forward to hearing about your continuing experiences as your cars age. I'm particularly interested to see how fluid viscosity and wear metal content changes over time.

Hope that you continue to enjoy mpg improvements (not sure why this is the case since Redline seems to have higher viscosity relative to ATF WS, which would explain why Ed perceives reduced drivetrain vibration with its use.)

 

I can't offer a scientific explanation. My experience is that even higher weight synthetic oilds provide better results considering less heat and lower friction. We used to run VERY thin oil in our transmissions and rear ends for qualifying and some short track races. We feared, and sometimes had catastrophic failures due to lubrication failure We switched to synthetic gear oils at more normal weights and never again lost a rear end or transmission. Lap speeds were the same or better, and heat was definitely lower, implying less friction. It's really hard to guage actual rolling drag in a race car because the aerodynamic and chassis setup play such a large role in the game. That's my experience...

 

I also suspect Toyota WS is good but not formula unique and I have had steller results with Redline products in the race cars and other personal cars. I'm trusting it here also. We'll see what happens. I'll post my oil analysis data for both the old and new and contribute to the knowledge of the community as I can. I don't recommend this to anyone else as I don't have any proof it will be OK.[/quote]

Thank you for weighing in. Maybe the WS fluid is a little on the thin viscosity side to help with mileage. WS is thinner than the Type T-IV in Gen 1's. Its the lowest viscosity available I think. It's probably the exact same formula as the Gen 1 Type T- except lower viscosity which will help mileage. With that thin of an oil I want the best GL-4 quality on the market. I would not feel bad losing 1 or 2 mpg's to run this stuff because I know its a quality fluid.
But like you I see no mileage hit either.My mileage has always suffered well before my move to Redline compared to other posters getting 50+ but I know why. My driving routine is really bad. Lots and lots of short trips.2 days of lots of short trips takes 2 days of good rolling to get the numbers back up. I know that and have a lifetime of 48 mpg's. I'm really happy with that.
Like you I have had excellent results with Redline in every car I have ever owned in the last 10 years. Thats why I put it in this car.You only have to use there trans oil once and your hooked. It's fixed more shi**y running transmissions for me then I can remember.
Hey have you tried there motor oil? I know its expensive but I'm going for a 10K+ change so trying it once. So far so good. Its the strangest feeling stuff on your fingers. Pure high quality poly ester base stock. But the car runs awesome. I got Water Wetter in the Inverter coolant too! No aluminum corrosion and its the same color! Woo Hoo! :cheer2:
Thanks again.

 

I would feel better by a claim backed up by a mileage record such as GreenHybrid.com, Fuel Economy, or other per tank record. However, I documented a reduction in cold weather, hill rolling resistance when I changed my 53k, worn out Type T-IV for Amsoil ATF. The worn out Type T-IV had lower viscosity but it really was 'worn out' and loaded with particulates.

One of these days I'll buy a perfectly, brand new, 1 mile Prius and do the "new car" break-in experiments. Of course my neighbors and friends will wonder, "What's wrong with your new Prius?"

I'll have to answer, "Nothing but I'll find it!"

Bob Wilson

 

Bob, I loved that comment. It's so fitting in this forum and others I frequent. We continually dissect stuff to learn and get better until I really think we collectively know more than the designers in some cases! Keep up the good work!

 

[/quote]

Thought about it and again there's a better way. But, I do agree on specific parts like water pumps etc your better off paying the extra money and going OEM instead of say NAPA.
But, after 15,000 miles on my 07 I now notice some very minor clunking up front in the suspension. Given the circumstance I know exactly what that is. Its the shi**y stock struts.
Another 10,00 miles and they will start to annoy me. The tires at 15,000 are also ridiculously noisy too. But concerning the struts I will not replace them with stock struts because there's alot better out there. KYB or Tokico both make excellent struts with better life and feel. Major upgrade for almost the same money. "Keep the feeling"?
Not so much.

All I'm saying is there's alot of better options out there for your money concerning this car.

 

Hi Ed,

Please note that KYB is the original equipment supplier to Toyota for the front struts and rear shocks. Its not obvious that the KYB-branded shocks are superior to Toyota-brand shocks in this particular instance.

I'm not aware that Tokico produces struts/shocks that fit Prius; if you've found a source for these please let us know. Thanks!

 

[imglink]Please note that KYB is the original equipment supplier to Toyota for the front struts and rear shocks. Its not obvious that the KYB-branded shocks are superior to Toyota-brand shocks in this particular instance.

I'm not aware that Tokico produces struts/shocks that fit Prius; if you've found a source for these please let us know. Thanks!

[/imglink]

Ok this car uses KYB struts but as the sales guy told me when I called the Shoxshop concerning availability of Tokico's there's a good-better-best deal with re-branded oem car parts. The after market KYB struts may be of better quality than over the counter Toyota parts. I hope so as I can see some degradation at 15K already.
I really like Tokico struts and would tend to use there product first but you are right in that Tokico seems to not offer a replacement strut for our car. We were both surprised about that. The salesman & me.I think that probably points to the fear most people have in what a special car this is and you must only use Toyota parts.I wish they would offer them though.
They ride great.