transmission/differential fluid

[westex39]

Is the transmission and differential fluid on the Prius the same fluid? Does it have a common reservoir or sump? How do you check the fluid level?
Thanks in advance for your replies.

Westex

[hobbit]

Yup, the "punkin" sits at the bottom/back of the transaxle unit,
lubed by the same 4 or so quarts of fluid as the PSD. There's a
fill/level-check hole on the front of the case. See this for some
more details; which way you'd go at changing it is optional but if
you're an '07, you don't have to worry about it till 50K or so.
.
_H*

[westex39]

Thank you very much Hobbit.
That's what I call an answer and then some.

Regards,

Westex

[Bill Merchant]

Or maybe Mr. H is advocating fluid changes more frequently than Toyota suggests... Does Toyota ever recommend changing the transmission fluid?

[Frank Hudon]

on page 24 of the 2k4 Prius Owners Supplement Manual it say's.. replace the fluid every 72 months or 96,000 Km's. 96,000 km's = approx 60,000 miles.
Edit: same page same recommendation for the 2k3 Prius.

[Bill Merchant]

Thanks, Frank. I went online to look at the scheduled maintenance for a 2007. At 60K miles it says:

Replace engine oil and oil filter 1
Rotate tires
Replace cabin air filter (if equipped)
Replace engine air filter
Inspect the following:
- Ball joints and dust covers
- Brake lines and hoses
- Brake linings/drums and brake pads/discs 2
- Differential oil
- Drive belts 3
- Drive shaft boots
- Engine coolant 4
- Engine valve clearance
- Exhaust pipes and mountings
- Fuel lines and connections, fuel tank band and fuel tank vapor vent system hoses
- Fuel tank cap gasket
- Radiator, condenser and intercooler
- Steering gear box
- Steering linkage and boots
- Transmission fluid or oil


Additional Maintenance Items for Special Operating Conditions:

Driving While Towing
- Replace front differential oil
- Replace transmission fluid or oil
- Tighten nuts and bolts on chassis
Driving on Dirt Roads or Dusty Roads
- Tighten nuts and bolts on chassis

Applicable Footnotes:
1) Reset the oil replacement reminder (“MAINT REQD”) light after replacing engine oil, if vehicle is equipped with this light.
2) Inspect thickness measurement and disc runout.
3) Initial inspection at 60,000 miles/72 months. Inspect every 15,000 miles/18 months thereafter.
4) See Maintenance Definitions (Engine Coolant) for details.

So now Toyota says to inspect the trans/diff oil at 60K and replace it if you've been towing, which they expressly tell you not to do. I'm not saying you shouldn't, I'm just saying Toyota doesn't recommend it.

[jdenenberg]

<div class='quotetop'>QUOTE(Bill Merchant @ May 18 2007, 02:45 AM) [snapback]444703[/snapback]</div>

Thanks, Frank. I went online to look at the scheduled maintenance for a 2007. At 60K miles it says:

Replace engine oil and oil filter 1
Rotate tires
Replace cabin air filter (if equipped)
Replace engine air filter
Inspect the following:
- Ball joints and dust covers
- Brake lines and hoses
- Brake linings/drums and brake pads/discs 2
- Differential oil
- Drive belts 3
- Drive shaft boots
- Engine coolant 4
- Engine valve clearance
- Exhaust pipes and mountings
- Fuel lines and connections, fuel tank band and fuel tank vapor vent system hoses
- Fuel tank cap gasket
- Radiator, condenser and intercooler
- Steering gear box
- Steering linkage and boots
- Transmission fluid or oil


Additional Maintenance Items for Special Operating Conditions:

Driving While Towing
- Replace front differential oil
- Replace transmission fluid or oil
- Tighten nuts and bolts on chassis
Driving on Dirt Roads or Dusty Roads
- Tighten nuts and bolts on chassis

Applicable Footnotes:
1) Reset the oil replacement reminder (“MAINT REQD”) light after replacing engine oil, if vehicle is equipped with this light.
2) Inspect thickness measurement and disc runout.
3) Initial inspection at 60,000 miles/72 months. Inspect every 15,000 miles/18 months thereafter.
4) See Maintenance Definitions (Engine Coolant) for details.

So now Toyota says to inspect the trans/diff oil at 60K and replace it if you've been towing, which they expressly tell you not to do. I'm not saying you shouldn't, I'm just saying Toyota doesn't recommend it.
[/b]

Bill,

Don't believe everything that you read. I changed out my Trans Fluid (Toyota type WS - 2004 Prius) at 61,000 miles and sent a sample of both the used and virgin fluid to a lab for testing. The lab report said that it was in reasonable shape, but was just about used up. As Hobbit said, changing the ATF at 60,000 miles is probably a good idea.

JeffD

[hobbit]

Oh, right, you guys probably haven't been following the ongoing
thread in the prius_technical_stuff yahoogroup [highly recommended]
about Bob Wilson's oil and tranny fluid testing marathon. Folks
there have concluded that even 50,000 mi on ATF-WS under normal
conditions is pushing it. Bottom line is that Toyota may have
stretched the intervals on some of these fluids, if for no other
reason than it looks like better reliability/hands-off in the
schedule. To their credit, even the shorter intervals that the
owner community has determined are still refreshingly long, esp.
by contrast to fluid change intervals in cars only ten years ago.
This is largely because of improved chemistries. But you still need
to be careful to use the OEM fluids -- the aftermarket for EXACT
equivalents is still very sparse.
.
Data collection is ongoing; that's why I sent off my sample to Bob.
.
The scattered reports of BURNT motor windings in the Classic prius
are also causing increased skepticism of the change interval of the
T-IV fluid in those. Remember, the fluid is in direct contact with
the motor windings, and while it's normally an insulator, time and
distance may start changing that.
.
_H*

[dmckinstry]

<div class='quotetop'>QUOTE(hobbit @ May 17 2007, 04:52 PM) [snapback]444505[/snapback]</div>

Yup, the "punkin" sits at the bottom/back of the transaxle unit,
lubed by the same 4 or so quarts of fluid as the PSD. There's a
fill/level-check hole on the front of the case. See this for some
more details; which way you'd go at changing it is optional but if
you're an '07, you don't have to worry about it till 50K or so.
.
_H*
[/b]

I'm approaching 50k on my '05 now. Any special gotchas in changing the fluid. Am I better off to have the dealer to it with my next oil change, or do it myself. e.g., how much more would the dealer charge than I would pay for the fluid doing it myself? I've been sticking to the dealer for oil changes, just to simplify warranty issues.

Dave M.

[Frank Hudon]

about a year ago here on PC we had a big discussion about the PSD fluid and I made a filter adapter and installed a Toyota Torgue Converter filter for a Toyota forklift on my 2K3 Prius and today I changed the filter and the PSD oil as well as dropped the pan and cleaned it out. Not a lot of contaminants on the magnet in the pan or the magnet that I put in the filter adapter. Took a sample and will send it out for analysis next week. It looks clean and red just like the stuff I put in, Type T-4 as I have a case that I bought last year. I'll post the results from the first test and this one so people can see if a filter is a good addition or if it's not needed.