Transaxle Oil Analysis

The transaxle fluid analyses that Bob Wilson has been collecting are in the files section of the yahoo! toyota-prius-sat2 group.

I'd like to get his OK before copying them all over here, but I doubt that he would object.

Dr. Evan, I *strongly* agree that Toyota ought to publish something official about transaxle maintenance. Guidelines for acceptable levels of contaminants and viscosity would be ideal! But perhaps too much to hope for...

 

I really think Toyota as well as all of the other automobile manufactures know how quickly the fluid degrades. It is just a marketing/planned obsolescence issue. Even with the poor quality of the fluid from 40-50k on, the transaxle will still last well over 100k miles. As long as it fails after 100k miles, the dealers can just say that "parts start to wear out after 100k miles".

Toyota will never admit that there is a problem with the fluid, because they already know how it ages.

 

Hi folks,

I kinda like collecting the reports in one, easily accessible area with good fetching characteristics. I'm not familar with PriusChat files organization but feel very comfortable with the Yahoogroup files. I won't stop anyone from making a snapshot copy but understand my future reports will still go to the Yahoogroup area.

As a way to move forward, I'd like to suggest the non-PdMA reports (Blackstone and others) get collected here and we have a reference to the PdMA files in the Yahoogroup. Eventually, in the Yahoogroup, I plan to make a master spreadsheet with all of the PdMA samples so folks can do their own analysis. But it gets harder when dealing with reports from different labs having different sets of data. It also raises the question of reproducibility between labs.

Regardless, I'll put in a reference to my DRAFT report to this area shortly.

Bob Wilson

 

<div class='quotetop'>QUOTE(efusco @ Oct 13 2007, 02:18 PM) [snapback]525220[/snapback]</div>

I'll believe that Toyota feels the fluid will last to 100k miles when I see ONE fluid analysis beyond 50k that shows the fluid is OK. I just don't think it is possible for a fluid to go that far and be OK. Especially with all of the break-in crud in there.

 

Don't worry efusco, I don't take anything personally. I am just stating my opinion. As far as the limits of wear metals, there is nothing special about the planetary gear system in the Prius. The acceptable limits that Blackstone uses are based on data from many, many analyses. It is not necessarily the drop in viscosity that matters, it is just that the fluid is so contaminated.

 

<div class='quotetop'>QUOTE(efusco @ Oct 10 2007, 06:29 PM) [snapback]523870[/snapback]</div>

Most knowledgeable independent technicians recommend regular fluid changes on "100K fill" or "lifetime fill" transmissions, hybrid or not. So for the most part, the problem takes care of itself. Some Toyota dealership techs recommend 60K changes, as well; if they don't like the factory recommendations, the are not shy to say so.

However, Toyota does help create a barrier to prudent service; some owners will pull out the maintenance schedule and pronounce the tech, who is recommending regular fluid changes, as "a rip-off."

I cannot emphasize enough the importance of finding a knowledgeable technician, and sticking with him or her throughout the life of the vehicle.

 

<div class='quotetop'>QUOTE(jk450 @ Oct 23 2007, 01:33 PM) [snapback]529383[/snapback]</div>

How?

When I've taken my Prius to the local Toyota Service center where I only get to speak with the ticket writer and never the technician. I've visited different independent shops but once again, I'm buffered from the technician by the order taker and cashier.

What is the preferred technique? Should I insist on interviewing each technician to select the one I want to work on my car? If they don't let me interview their staff, just leave and take my business elsewhere?

This is a serious question because to propose "finding a knowledgeable technician" without providing specific details on how to accomplish this task is incomplete.

Bob Wilson
<div align="center"></div>

 

Bob it just goes to show you how all dealers are different. When I first got my Prius at the first dealer visit for an oil change, I was introduced to the Prius tech. He was the one who told me why it's important not to overfill the oil ect. and he's the one who told me to inflate the tires to 42/40 so they don't wear out early. I guess I'm lucky I got a good dealer.

 

<div class='quotetop'>QUOTE(paprius4030 @ Oct 26 2007, 07:26 AM) [snapback]530640[/snapback]</div>

maybe he is a Priuschat user

 

<div class='quotetop'>QUOTE(paprius4030 @ Oct 26 2007, 06:26 AM) [snapback]530640[/snapback]</div>

In fact, I picked up my Prius in Ft.Worth only to discover later, thanks to similar boards, that 32 psi tire pressure is too low and the importance of not having 5 quarts, an overfilled, oil tank. Even now, I wonder if the original owners of my Prius had decided it would never achieve the rated MPG because of these two dealer practices.

I've had quality problems with Firestone too. For example, not only reducing the tire pressure to 32 psi but taking off my tire pressure caps that would have shown what they did. Also, there are two dings in my passenger rear door that probably happened in the Firestone shop. Yet it was the local Toyota dealer who told me about cleaning the throttle plate and avoiding a potentially expensive ECU change.

Finding quality service is not a trivial problem and the information we share here is critical to being able to tell. Owner-operators are key to that mix in providing feedback. Furthermore, some of us have the time, interest, tools and discipline to investigate areas that even the best technician might miss. I was particularly pleased that two west coast mechanics had come to the same conclusions I had formed about the importance of a shorter interval, Prius I (NHW11,) transaxle oil change. My contribution has been the use of transaxle testing results to quantify the problem.

"Finding a knowledgeable technician" is not trivial nor is everything an owner-operator posts accurate. I've been corrected in the past but with better facts and data. Criticism based upon better understanding of our vehicles is always welcome but criticisms based upon who makes a comment is not helpful. After all, this place would become extremely quiet if we all had to pass a "knowledgeable technician" test to post.

Bob Wilson

 

How about adding a guide for DIY transaxle change to this sticky or the other transaxle sticky. I know it is simple drain and fill but how accessible are the plugs. I have looked during an oil change and did not find them and I saw a guide by Hobbit and he took off alot of stuff to access the plugs. He was doing other work also so I hope it is not neccessary to remove parts to access the plugs. Someone who has done it please post, I am at 55k.

 

<div class='quotetop'>QUOTE(etyler88 @ Oct 26 2007, 07:17 AM) [snapback]530680[/snapback]</div>

I just did it at 53,000 miles. There is no need to take apart all those things on top of the engine. I saw those pictures too.

Look under the tranny. There is no sump pan to remove or filter to replace. There is a 24mm hex bolt and a 10mm allen bolt. Purchase the identical washers from Toyota when you purchase the WS tranny fluid.

I went to Wal-Mart auto section and purchased the funnel with a plastic tube. The funnel and tube had a cover on each. This is important since I don't want any dirt on future fluid changes. I then purchased a much longer plastic tube so I could rest the funnel at the top of the engine compartment and thread the plastic tube down to where the 24mm hex plug is.

First, open the 24mm hex plug. WARNING look at the pictures of which ones not to open. You can see some rubber hoses connecting very close to those plugs. The 24mm one I am writing about is higher on the tranny. Eventually, I'll post some pictures of everything. When you open the plug, there will be a hissing noise to let in some air. When the tranny heats up, air escapes through a one-way valve creating the partial vacuum. When you open the 24mm bolt, you are letting the air back in.

Second, open the 10mm allen bolt and watch the dark grey tranny fluid come out. Clean the plug with brake cleaner--there is a weak magnet that collects some metal. Maybe next time I'll replace or add a super magnet. Anyway, replace the washer and plug, tighten.

Third, while you hold the plastic tube into the hole left by having removed the 24mm plug, have your friend begin by pouring 4 quarts of Toyota Wild Sh*t (WS) tranny fluid. Since Toyota measures their quarts exactly (I tested) you can just put in the four quarts you purchased.

Fourth, clean and then replace the 24mm hex plug and washer and you are good to go. You will find the drive smoother and kick yourself in the pants for not having replaced this fluid ($25) plus parts much much earlier.

I read that someone always replaces all the oils and filters (motor, tranny, differential, etc) at the first 5,000 mile mark to get rid of the early metal shavings, then puts in synthetics and utilizes long change intervals.

Since the WS fluid is crapping out at around 50,000 miles, I think I will be changing at 70,000, 90,000 and every 30,000 thereafter.

Good luck.

On another note, I have been researching motor oils and apparently, there is a semi driver that went 409,000 miles on a single oil change. He had bypass filtration (2nd filter at 1 micron) and changed filters every 20,000 miles using Amsoil. For cars without the bypass filtration ($200 plus installation) Amsoil is recommending 25,000 or 35,000 depending on oil or one year, whichever comes first. I am still researching but now using Mobil 1 Extended. I spoke to a dealer earlier tonight, who said when he changed his oil at 30,000 miles, it came out goldish brown in color. He was only using Amsoil regular filters--no bypass.

 

If all you want to do is change the tranny fluid, you certainly don't
have to pull all the stuff I was playing with in the maint50k page.
We did a much simpler job [with a suitably extended funnel, that's
the important part] on Jesse's car, detailed here. Bob's got the
analysis from that old fluid posted someplace but I haven't had time
to look for it yet.
.
_H*

 

Thanks Hobbit and Dr. Rocket. I am fully confident to perform the service now. Great pics and explanations.

 

<div class='quotetop'>QUOTE(Dr Rocket @ Oct 31 2007, 01:43 AM) [snapback]532795[/snapback]</div>

That was probably me. With my FJ Cruiser, I did the front and rear axles, and the transfer case, at 1,200 km. Front axle drained golden, the transfer case was clear - as if it had just been put in - but the rear axle was already BLACK with a lot of fuzz on the magnet

I decided to go with Mobil Delvac Synthetic 75W-90, which is a commercial gear lube. In applications intended for extended servicing, it meets the warranty requirements of Rockwell at 500,000 mile intervals for their 750,000 mile warranty. That interval obviously does not apply to a passenger vehicle with a 3 litre axle capacity, it is intended for a commercial design with a 20 litre capacity.

I refilled the front axle and transfer with the Delvac, and put cheap 80W-90 in the rear axle. I drove around a bit and had to drain/refill the rear axle a couple more times until it came out clean, then refilled with the Delvac

A couple of weeks ago, at around 10,000 km, I decided to service the axles again. Front axle came out clean, like I had just put it in. The transfer case fluid was also new looking. I think I will leave the front axle and transfer case to every two years, possibly longer.

The rear axle was very dark brown. I'll probably do the rear axle yearly.

When I put in the Delvac, I gained 2 mpg. Currently, if I drive at speed limits of 90 km/h, I can get 29 mpg. That's very good for an FJ. A lot of the habits learned on the Prius will work on conventional vehicles too

 

<div class='quotetop'>QUOTE(bwilson4web @ Oct 26 2007, 04:24 AM) [snapback]530623[/snapback]</div>

i wrote a long article on this a long time ago that was barely viewed.