Changing the PSD fluid?

Rick phone the Cat dealer in PHX and ask them how much they charge for a UOA Mine was less than $20 CDN. If you think that there is water in it definately do a UOA. Before you get more miles on it and have a big problem with Toyota warranty.

 

<div class='quotetop'>QUOTE(htmlspinnr @ Aug 7 2006, 09:27 PM) [snapback]299474[/snapback]</div>

possibly but why chance the hassle of trying to claim it if you have h2O in it now. Straight to Toyota with UOA sheet in hand.
Edit: on the 2k4's there was also the reseal of one of the plugs thru the PSD case that was the subject of a recall. Along with a HV computer flash. It apparently let moisture in the PSD.

 

well it might have been a long time ago but you've been dirving it for a long time as well. Time to give it to the wife and get a new one! Oppps not an option..... oh well I tried.

 

<div class='quotetop'>QUOTE(htmlspinnr @ Aug 7 2006, 09:13 PM) [snapback]299398[/snapback]</div>

Rick

Right, without the results of the UOA you won't know for sure exactly what is in the old fluid. Sometimes folks will mistake a "milky" appearance for water when it's actually very fine metallic residue. Like metal shavings. In some applications that is normal and expected, which is why you have magnets on drain plugs and prudent change intervals.

A lot of OEM's are calling things "lifetime" fluids, which I wonder is their defined lifespan of maybe 100,00-150,000 miles and no more. For example, my dad has a 2003 Buick LeSabre and GM claims in "normal" use the ATF is a lifetime fluid, in "severe" use change it every 100,000 km / 60,000 miles.

It's a lease return car that my folks bought in 2004 with around 20,000km on it. The first thing I did was insist the dealer service the transaxle conditional to sale, and I wanted to be there when he took the pan off. You should have seen the crud in the bottom of the pan. "Lifetime" fluid my nice person.

As far as convincing your wife about the importance of prudent fluid change intervals, good luck. I'm sure she is a nice gal, but she is still a woman. I'm happily single for a very good reason!

jay

<div class='quotetop'>QUOTE(Frank Hudon @ Aug 8 2006, 12:41 AM) [snapback]299503[/snapback]</div>

Hehehe I was thinking the same thing. We may be responsible for the inevitable breakup of their marriage if we keep this up.

 

<div class='quotetop'>QUOTE(htmlspinnr @ Aug 8 2006, 11:38 AM) [snapback]299645[/snapback]</div>

Rick

Much like how if you want to change the gear oil in many domestic pickup trucks, you have to remove 10-14 bolts and pry off the sheet metal differential cover, let all the gear oil glop all over the place, and reassemble everything. On my 1984 Ford F-150 4x4, the only way to drain the front differential is to carefully drill into the case, and tap threads for a plug. Otherwise you have to siphon the gear oil out, which is a less than perfect solution.

Some folks seem to actually get a lot of life out of "lifetime" fluids, others usually get 100,000 miles or so and the thing quits on them. Car makers are in the business to sell you another model, not to have the current one last forever

As far as your marriage, I was just kidding. I'm sure your wife has many tender feelings for you.

j

 

<div class='quotetop'>QUOTE(htmlspinnr @ Aug 8 2006, 09:38 AM) [snapback]299645[/snapback]</div>

I thought your computer was the server back in Jan Feb 2004

 

<div class='quotetop'>QUOTE(htmlspinnr @ Aug 6 2006, 11:32 PM) [snapback]298871[/snapback]</div>

Feel free to use the virgin sample at this web page:

http://hiwaay.net/~bzwilson/prius/pri_T_cold.html

BTW, if you haven't sent the oil in, yet, could I pursade you to use an oil testing service that also does transformer oil break-down analysis? If you use PdMA, they do but they need a large sample, 400 ml will do. I would be happy to pay for the break-down voltage test.

Bob Wilson

 

<div class='quotetop'>QUOTE(htmlspinnr @ Aug 9 2006, 04:45 PM) [snapback]300426[/snapback]</div>

I put it in postal box and make sure the shipper knows it is an "oil sample" since such samples have to go by ground. I'd recommend putting the container in a separate, sealed plastic bag and in a nest of newspaper. You might give PdMA a call (see their address and number on the web page) and ask how to handle payment. I've bought Canadian stuff with my credit card but whatever works. I usually just buy a US Postal money order for $20 and include that with the order form.

PdMA has a form that I fill out (see word attachment.) Just change the fields to match your e-mail and name. I've also included the Type WS reference sample test id so you should get both your oil and the reference sample values in a single PDF file. Once you forward their report to me, I'll go ahead and order the breakdown voltage test, assuming there is nothing untold.

The standard test plus the 100© viscosity test runs $20 (US). If you want, you can order the particulate test, an extra $22 (US) BUT I'm not sure it does much good. For me, it has re-enforced the need for a filter but in the case of our NHW11, I'm more worried about the loss of viscosity. BTW, yours will be the second, Type WS sample and will nicely complement the sample we already have.

The oil breakdown test is important because one failure mode may be a short circuit. There isn't much in the case other than the oil and the particulates it carries. Once we have your sample, I provide PdMA with a baseline sample of the Type T and Type W to measure their 'virgin' breakdown voltage.

If your sample proves what I suspect, it may be possible to detect a change in the oil with a fairly simple probe checking the dialectric characteristics of the oil (not breakdown but related.) I'll need to do some more testing in this area but it has my interest.

The primary mechanical property we are interested is film-strength (how much pressure it takes for two flat surfaces separated by the oil to make contact.) That is a hard test to do with a particulate load in the oil since the particles would 'bridge' the film. However, the viscosity change, is good enough to give us a clue about what happened to the film strength.

Bob Wilson

 

well I've only put about 50Km's on the car since I did the install of the filter and hoses, been on holidays and got to thinking about that little 5/16" NF fitting screwed into the pump cover and how stiff that hose is and how the ICE shakes on shut down sometimes and figured a braket to hold it so that there would be less strain on the fitting and figured a bracket with an Audel clamp to hold the hose was in order. So have been home 2 days and with most of the chores caught up time for a bracket to support the hose.

 

if there's any opacity to the fluid I'd change it, the UOA just didn't justify it at this time. Clear like new and I'll keep an eye on it when I change the, new, tranny filter about every 10,000 miles.

 

Ok, at at time in my life I don't work on my cars, I have a 2002 clasic Prius and have been going "by-the-book" on maintaince. However, with over 100,000 miles I did not recall anything on transmission fluid.
So what's the deal ? I want to change it but should I use a systhnic or not. Anyone suggest a specific brand?The engine has only had systec from 500 miles. I just forgot about the transmission fluid. I intend to drive it until I retire to SA in 3 or 4 years. (another 100K miles)

 

<div class='quotetop'>QUOTE(captne @ Sep 16 2006, 09:34 AM) [snapback]320529[/snapback]</div>

currently there is only a choice of 2 PSD fluids for the Prius Classic. Toyota type T-IV or Amsol synthetic ATF. This is partly due to the electrical conductivity of the fluid as there is hi voltage in the PSD case. It's a fairly easy change on the Classic but you'll need a small pump to get it into the filler plug. Some have use a small funnel with a small hose threaded down and into the filler opening. Bob Wilson recommends dropping the pan and wiping down as much of the old oil as possible and replacing the gasket. I'd have to agree with him on that and it's cheap the gasket is under $10 retail. At 100000 miles your due for a change, probably past due.

 

<div class='quotetop'>QUOTE(captne @ Sep 16 2006, 11:34 AM) [snapback]320529[/snapback]</div>

I would very much like a sample of the used oil. Just put it in clean, dry water bottle (aka., polycarbonate) or polyethelyene (check with your pharmacist or urine sample bottle.) Send me a note and I'll reply with my mailing address. I'll get it tested and share the results:

http://hiwaay.net/~bzwilson/prius/pri_T_cold.html
http://hiwaay.net/~bzwilson/prius/pri_toil.html

Changing the oil is best done with the vehicle on a ramp and it isn't that hard to do. If you don't want to do it, get five quarts of Type T and the gasket from your local Toyota parts dealer. Either pay them to do it and/or find a trusted independent mechanic. Be sure to emphasize the need to drop the pan and wipe down everything and put the magnet back.

GOOD LUCK!

Bob Wilson

 

Frank and Bob did not mention Toyota type WS transmission as backward-compatible with the 2001-2003 Prius model. I was assured that it was by a top-notch mechanic, and have used it in my 2001 Prius now with no issues for almost 4000 miles.

Actually there is one issue: the fuel economy has increased by 8-10% due (we think) to the lower viscosity of this fluid. Nothing to complain about there though.

Bob is leading an effort to determine what the appropriate fluid change interval ought to be for Prius. I think he might suggest numbers as short as 15k miles, and some shops are already recommending 60k miles. I expect that we will end up converging on some number between those two.

 

<div class='quotetop'>QUOTE(tochatihu @ Sep 18 2006, 09:58 AM) [snapback]321131[/snapback]</div>

This 8-10% improvement is supported by a Dept. of Energy Prius transaxle study, the GreenHybrid.com database and references in a Toyota SAE paper. My studies have also given hints about the potential improvement.

The GreenHybrid.com database shows the NHW11 vehicles getting an average of 45 MPG and the NHW20 getting 48 MPG, a 6% improvement. Although many improvements were made between the NHW11 and NHW20, transaxle efficiency has a major effect since all power must flow through that part.

The Toyota paper "Development of New-Generation Hybrid System THS II - Drastic Improvement of Power Performance and Fuel Economy" (SAE 2004-01-0064) by Kiochiro Mutaq, Makoto Yamazaki and Junji Tokieda discusses the various changes and improvements between the NHW11 and NHW20. It includes a graph of torque loss that shows a subtantial reduction at low speeds, pp. 10. They go on to say, ". . . The main changes are the adoption of the ball bearings at the reduction gear, and low friction oil. As a result, friction loss is reduced approximately by 30% (Fig. 28)." That low friction oil is the Type WS.

The Dept. of Energy report "Report on Toyota Prius Motor Thermal Management" (ORNL/TM-2005/33) by J.S. Hsu, S.C. Nelson, P.A. Jallouk, C.W. Ayers, R.H. Wiles, S.L. Campbell, C.L. Coomer, K.T. Lowe and T.A. Burress shows a subtantial improvement in transaxle energy loss as the oil warms up. From 35C to 75C, the losses went down by 20%, pp. 21. Heating transaxle oil reduces its viscosity substantially, ~78%. The Type WS oil viscosity, 24.6/5.5 cSt, has 30% less viscosity than the original Type T, 35.3/7.4 cSt. A proportional savings, heating energy savings times viscosity change (20%*30%) will be a net 6%.

When looking at used transaxle oils, my studies indicate the Type T oil suffers a rapid viscosity loss, ~15% around 15,000 miles, and a high particulate and wear metal counts. However, the one Type WS sample had gone 61,000 miles with a 14% viscosity loss and half the particulate count of Type T at 53,000 miles. This makes sense if the Type T oil is too viscous.

Excessively viscous oil suffers higher shear stress and heating. The shear stresses are against the bearing surfaces. This heat and stress leads to local, point wear of the oil and some loss of bearing material. But there is one other aspect, silicon/aluminum contamination that suggests some dirt/grit ingestion. Even so, particulate matter in the oil, regardless of the source, makes the oil into a lapping compound and punches through the lubricating film. My hill rolling tests showed clean, Type T oil had an 11% lower rolling resistance than the used particulate laden Type T with a lower viscosity. This is one reason why the transaxle oil filter experiments are so important.

Doug's reported improvement, 8-10%, is entirely consistent with clean (no particulate), lower viscosity Type WS oil. We do not know the long-term, Type WS oil wear patterns in an NHW11, the data has yet to be collected. But IMHO, it has to be better than the 15,000 miles shown by Type T and without an oil filter, less than the 60,000 miles of the Type WS in an NHW20. I suspect that with an effective oil filter to capture the particulate matter, it would easily exceed 100,000 miles.

Bob Wilson