DRAFT Transaxle Oil Testing Results

etp, this may highlight the difference between Prius transaxle and conventional auto. trans. In the latter the fluid 'does work" while in the Prius it is only lube and heat transfer.

It is certainly possible that a Prius fluid change could mobilize varnish as passage-plugging goo, but it seems much more likely in the other systems.

 

Does PdMA still do oil analysis? Its website redirect to

R&G Laboratories, Inc or PdMA Corporation - Oil Analysis - Excellence in Lubricant Analysis

which does not seem to service individuals.

 

Makes you wonder if another type fluid would be better than tranny fluid. But I suppose 0W20 may be a problem for some of the parts/maybe. CVT fluid should work.

 

Monitor transaxle temperature?

How do you monitor the transaxle temperature? Can ScanGauge do it?

 

Latest data with RedLine D6 ATF

Good Morning Everyone,

As I reported earlier, I'm one of the owners testing the Redline D6 transaxle fluid instead of the factory WS. I made the change last year at 35K miles and had the factory oil tested as a baseline. Since then I have put 23K miles on the Redline oil and changed it for the first test sample. Total mileage at change was 57691. I had hoped to put more miles on but I've been out of town a lot. The car is used primarily for long highway trips, daily and weekly. The normal average mileage would be about 35K per year.

It looks like everything is in line or better than the first factory change except copper, phosphorus and Boron. The copper number went up to 19 but that looks similar to other people's data. The Boron value went way up to 268 - I don't know what that implies. Viscocity stayed up. I don't think I needed to change the oil again this early but I wanted the data. Anyone know what the Boron value would indicate? What does Phosphorus indicate?

My weekly mileage is right around 50MPG so the car is operating great and it drives excellent. I'll go for 35K miles on the next cycle and report again in a year or so.

Here is the quick data. Attached is a copy of the report with both sets of data.

Al 14
Cr 1
Fe 39
Cu 19
Pb 1
Sn 1
Mo 0
Ni 1
Mn 1
Ag 0
Ti 0
K 1
B 268
Si 42
Na 7
Ca 25
Mg 2
P 660
Zn 7
Ba 3
SUS Viscosity @ 210 F = 44.4
cSt Viscosity @ 100 C = 5.54
Flashpoint 425 deg F.
Water 0.0%
insolubles 0.0%

 

Thank you for the data!

I wonder what the error bars are on those numbers. Has anyone asked for them from the oil analysis companies?

 

Re: Latest data with RedLine D6 ATF

Both are anti-wear additives. For engine oils, phosphorus is usually part of zinc dialkyldithiophosphate. ZDDP is commonly used to prevent cam lobe wear in flat tappet engine designs, which are not found in modern motors

Boron is usually boron amide and is usually used as an inhibitor to control acid buildup. It can also show up as a borax, which would imply a coolant leak

Since boron is multi-source, the testing of other additives and compounds will determine if the source is an additive, or a problem

 

Some are expected ranges, eg a xW-30 should test out at around 9.3-12.5 cSt @ 100 C. Others are "universal" averages, which are expected ranges

Most oil analysis will provide an expected range

 

Thanks! What I meant was not the expected range but the uncertainty (error bar) of each measured value. For example if the amount of Al comes back at 14 as in the data shared by satwood, is it 14 +/- 1, or 14 +/- 10 ?

 

The testing lab I use, it's +/- 5%

 

Re: Latest data with RedLine D6 ATF

This is an encouraging result. I replaced my Gen II's WS with D6 in July, but haven't done a UOA yet--and haven't driven too many miles yet. I'd hope for even lower Si levels, given that this is the second fluid change. I'm now considering replacing the WS in my Gen III with D6, which is beginning to look like a low-risk venture.

 

Over 23k thats a lot of shear the D6 starts at 6.4 at 100 C so thats about a 13.4 % loss in viscosity, was there any increase in fuel consumption due to the heavier fluid?

 

I just changed my transaxle fluid at 56k miles (2004 prius). Still looked pretty good with a red tinge to it still. Probably didnt need to be done, but its done now! No point getting it tested really as it looked good.

 

Huh, my '04 fluid was almost black at 12,000 km. Maybe our -40 winters don't help much

 

This is Rich from Hopkinton, MA. I have a white 06 with pkg 7. Almost 60K miles. I've been using Mobil 1, 5W-30 and Fram filters, changing at about 5K.

Re maintenance. The spark plugs were never mentioned. As they are Iridium tipped, is

the 100K recommendation of the owner's maintenance manual a good number?

Separately, what is the consensus on Engine Coolant and Inverter Coolant, mileage-wise?

 

Actually the maintenance schedule shows 120K mile replacement intervals for the iridium spark plugs. I changed the plugs on my 2004 at ~99K miles, the engine seems to run a bit better and mpg improved somewhat.

I would say that you should observe the maintenance schedule regarding the coolant: 100K miles to replace the factory fill; then 50K miles between subsequent changes.

 

i have an 04 with 70,000 miles. when i take it to the dealer for transaxle fluid change, what will they use, what does the owners manual say? thanks in advance!

 

Toyota dealerships have the WS fluid, which is called for in all Toyota automatic transmissions, eg the 5 speed auto in my FJ Cruiser

Others have used different fluid. IMHO probably doesn't make any difference, the cvt in the Prius has gears, a planetary gear, and a transfer chain. No torque converter or clutches like a conventional auto

Good luck getting an American Toyota dealership to even change the fluid. They usually claim it's "lifetime" or they will try to upsell you on a "flush" procedure, which is clearly impossible for the +04 Prius anyway

With my '04, my dealership wanted $65 to drain and refill the cvt. That was reasonable

Let us know how it turns out