interesting transaxle fluid UOA from BITOG

thanks! seems easy to deduce that fluid changes are required for those keeping their prius past warranty, but more difficult to figure how early and how often.

 

I never did mine until 140 k miles. I guess I should have saved a sample for comparison.

Maybe when we do @mmmodem s at month end, we could save a sample (if he still wants to change it that is ). He's probably around 122 k miles now on his PIP.

How much and what type of container do they usually accept for samples?

 

I've done three drains now, last one just recently around 65,000 kilometres . Guess I can back off for a while, lol.

It's cheap and easy, hardly worth debating.

 

you sign up on their website & they'll send you a container /

 

$28 seems rather steep for analysis (almost as much as the fluid).

But the kit is free.

 

Damn, did you attach a GPS to my car when I wasn't looking? 122,500. I'm still down for the change.

Oil analysis? eh... The problem is we don't know what acceptable values are. Aluminum at 555 ppm is high compared to universal averages but if the car is otherwise running smoothly, then is it really too high for a Prius V? I used to read BITOG religiously as it was and still is the premier source for engine oil related expertise. However, this kind of data collection is just too anecdotal. Someone who always changes their oil every x number of miles with aluminum less than 47 ppm never has transmission failure. I never had transmission failure either and I changed it at 100k on my previous two vehicles.

I'll agree to that!

 

The only way to establish a baseline or determine what is "acceptable" is with data. Not sure how Blackstone reports or established the averages, but I assume it is through samples of the same variety (maybe same year or same generation, etc), then they can share their thoughts on the results.

But at $28, the cost is high. It would be interesting to know what the metallic content in the sample is. When we drained mine at 140 k miles, the amount of loose particulate in the drain pan was low, but there was some.

It might not change your decision, but might help decision makers in the future

 

to put it in perspective, I do think changing it at least every 60,000 miles is a good idea, and i'm doing it myself (makes me feel i care), but we really have ZERO proof that it extends tranny life. the whole metallic particle "sandblasting" idea sounds logical, but it could easily be FALSE (if the particles are very small). BTW, the shorting issue was frequent on gen 1 and 2 (IIRC), not so in gen 3. The wingdings are not exposed now, but embedded in resin. i gave up up on the idea that BITOG members are really experts long time ago. many of them are just teenagers interested in cars or working in oil change places.

 

Not anecdotal if you know how to read a report. Tells you alot. Universal numbers as a reference work pretty well because as far as the fluid is concerned its basically a manual gearbox.

But the most important number you should be interested in especially concerning a Prius is how acidic the fluid has become. That tells you how the life extension pack is working in that particular sample. That is represented by the TAN. Total Acid Number.

I have run high performance trans fluid in my G2 since birth now at 110K. It has no calcium or any life extending minerals its pure base stock. On subsequent UOA's it showed excellent contaminant numbers but the Tan started to creep up at about 40K miles so for me that's a fluid change about every 4 years.

I have seen many Blackstone reports here but none showed the TAN so to me on this particular forum and car a Blackstone report is somewhat worthless without that comprehensive TAN number.
TAN tells me how much life is left on that fluid. Otherwise all your looking at is how much contaminants it has. A Blackstone test may show low contamination but you'll have no idea what the TAN is.

Use Lubeguard they include the TAN for free.

On the OP's attachment from Bitog that poster is using the wrong fluid. The Amsoil he's using is a D4 T-IV viscosity. His 2013 requires WS which is a D6 viscosity.
So he will probably see a mileage hit.
Plus his aluminum number is concerning.

Bottom line replacing the trans fluid just once after break in will greatly increase the transmission life.
The break in is where all the wear comes from. My G2 from brand new to 5,000 where I did the first fluid change showed alot of wear. Subsequent 40K UOAs showed very minor wear from there on. F

From what I have seen here so far on this forum the G3 is showing even more wear at break in.

 

What you said makes sense. Black ston

What you are saying has logic to it. Blackstone could do better to hire you to write their comments. Scott, however, comes off very "BITOG" for lack of a batter word. I've read many Blackstone comments and they are like this. "Your numbers are high compared to our other tests, therefore, you need to change out sooner." A does not equal B.

 

I'm using AMSOIL Signature Series Fuel-Efficient Synthetic Automatic Transmission Fluid, of which the cSt at 100 is 6.3 Stock Toyota ATF WS is 5.5 (based on a UOA from Blackstone. Their sales literature says it ok to use in transmissions requiring WS. Not an exact match but close enough for me. So far I haven't noticed a fuel mileage difference.
Im not sure what the aluminum is from. I haven't seen one of these transmissions torn apart yet.

The Scott is me lol. Thats Blackstone addressing me.

 

It would be a good idea to change it after break in. Then some interval afterwards like 60,000 miles sounds reasonable. The only true way to know the interval would be getting UOA's done to determine. Its hard to say there is ZERO proof of life extension. Based on every other gearbox, in the world keeping the fluid to a lower ISO 4406, number maintaining the cleanest fluid will increase bearing life. My profession is keeping industrial machinery running as long as possible, dealing with Tribology is one aspect. I guess it boils down to how long you plan on keeping/driving your vehicle.

I was skeptical of the sand blasting idea as well that's why I asked if he had any pictures.

 

if you are really serious about UOA, you should have done particle count. The cheap analysis that's marketed as UOA is simple spectrophotometric test that looks only at metals in the very small particles (5um IIRC) and detects the normal wear and tear, that don't necessarily correlate with abnormal wear. The abnormal, catstrophic failures are heralded by numerous large particles. as tribologist, you should know it well.

 

I was testing Blackstone out with this one. The price was a little much. Next time im going to send it to our supplier lubrication engineeres.

 

Agreed. I'd like to know what that baseline life is. If it increases the life from 200,000 miles to 300,000 miles, then we should all the fluid regularly. If it increases life from 1,000,000 to 1,500,000 miles, I'm not going to care. It's doubtful I'm keeping the car that long or that other components in the car will last that long.

I still hear my 9th grade teacher scolding me for randomly typing on the Apple IIe in class. She said it will decrease its life by that many presses. I countered with the keyboard is manufactured to last over 20 years worth of presses way beyond the lifetime of the computer. She said, waste not, want not or some such nonsense.

 

I drained transaxle fluid on our 2010 at the one year mark, around 15,000 km. I subsequently changed it around 40,000 km and 65,000 km. The first drain was by far the darkest looking; after the latest I resolved to leave it be for a while, maybe forever, lol.

 

I've pretty much worn off the little nubs on my current keyboard's home keys. Only been using this one 4~5 years.

 

The letters are rubbing off on my keyboard as well. I was forced to buy a new one last month (got a mechanical keyboard) because I'm teaching my 6 year old how to type "nick toons" in YouTube.

Alright, you got me. I concede, you are right and my 9th grade teacher may be right, there may be other aspects of "lifetime" that I have not accounted for. Alright, @Raytheeagle if I don't make it next weekend, I'll definitely need your help to change the oil on another day.