Should I get a transmission flush?

No flush needed, just drain and refill with correct fluid.

 

There's nothing risky about doing it. And I'd refer to it as a replacement, or drain-and-fill; no need for flush, which implies multiple changes. A single drain and fill replaces about 90%. My only comment would that it'd be better to have done this about 60,000 miles back, or even earlier.

Use Toyota ATF-WS, raise the car, level it, remove fill bolt first (for safety), then drain bolt. When filling use a funnel with a long tube, fill 'till it starts coming back out, you're done. 4 quarts (or liters) should be more than enough.

Besides the fluid it'd be worthwhile getting replacement washers for the two bolts. Maybe someone can post 2nd gen Repair Manual instruction on this. I only have 3rd gen. FWIW, torque for fill and drain bolts is 29 lb/ft, for both. That's 3rd gen.

 

Welcome to PriusChat, and to answer your question, as I said in another recent post, I had the transmission fluid in my 2009 Gen II changed at around 90k. I'd read somewhere hereabouts that the first transmission oil-change is usually quite important as it's the first time all the nasties and grotty stuff gets to be flushed out of the system since it was first assembled. OK, it can be done by you (if you have the tools and are handy with a wrench), but I used the dealer since although I have a garage & tools, I don't have access to a lift or a pit, and then there's the question of disposal! - hope this helps - Wil

 

I think transmission flush for the Prius is not recommended. Instead a simple drain and refill is recommended.

I would say that at 95K the transmission is due for a drain and refill. I had done the same for my 2008 Prius at 90K miles. If you are worried that you have waited for too long and now the procedure could damage the transmission, I don't believe that is the case.

BTW it is easier to drain and refill the transmission on a Prius than it is to change oil. If you are comfortable changing the oil in your car, I would recommend doing it yourself. That way you can be sure that it gets done right.

 

Anyone that takes used motor oil will take transmission fluid. I've specifically told our place it's transmission fluid, they just say to dump it in, same place. Up here, anyone doing oil changes will take DIY'rs used oil, filters and empty oil bottles.

 

…thanks! I'll remember that next time!

 

It's by no means difficult, but I'd rate it slightly harder. You need to raise and level the whole car. And since it's done so irregularly the bolts are a little more entrenched. And it takes a special funnel/hose contraption, or some sort of pump. I prefer the funnel. I guess the main issue is it's an infrequent service: you get more used to oil changes, lol.

 

95k here, too. How much should it cost for labor/fluid?

 

I can't find the original work order, but here's what I had in my log: "…change engine oil & filter, change transmission oil, rotate tyres, state inspection. $177.00" (labour rate is $107/hour (local dealer)) - hope this helps - Wil

 

Check this "cost thread" from a couple of weeks ago...

Transaxle fluid change -- Current $$$ from dealerships | PriusChat

 

Reasonable would be $80~100. The fluid and washers are around $40.

 

Its not necessary to level the car. That's alot of work and useless. The trans take 3.8 to4 quarts of fluid. You don't have to have the car level to figure that out? A little over hurts nothing.
Its essentially a manual gearbox.

Lift the front of the car up high enough to get a breaker bar on the input bolt. Dump the fluid out let it drain for a while. Snake a small funnel from the topside into the side fill hole and fill it up. Bolt it back up.

You can use WS or Maxlife from Walmart or alot of other fluids are available. Lots of talk about other fluids on Bitog and how crappy WS is. This car could care less. I use Redline D6 since 1K miles and have changed my fluid going on 4 times now including stellar UOA's that I have posted here.

Instead of wasting alot of time leveling the car put that time into changing the Inverter/Trans cooling fluid since your going to be under there anyway the cars jacked up high in the front ready to go and the bolts for that are right next to the trans bolts. New coolant REALLY helps the car's performance and life. The Inverter is the hardest working component in the car and very hard on the coolant. You will get instant mpg increase with new Inverter coolant. The cooler the Inverter is the more efficient it is.

I change both the trans fluid & coolant every 30,000 miles which for me is every 3 years. Car runs like new.

 

As mentioned above, the CVT is essentially a manual gearbox and it only has a few moving gears, no pumps or valves. The motors and gears just sit in the fluid. There is no hydraulic pressure or action. No radiator, either. No need to flush as you might a standard AT.

 

Andrew the gen2 Prius transmission does have a pump to circulate the oil, but no filter. The oil is not cooled directly but is cooled by a coolant jacket with this coolant being pumped by an electric pump to a radiator for cooling. The same coolant also cools the inverter.

John

 

I would never recommend a transmission flush for any vehicle. The reason a transmission flush can be damaging to the transmission, especially on older vehicles, is because the machine is delivering cold fluid into a warm transmission and this can warp intricate transmission components due to rapid temperature changes.

All you want is a drain and fill as previously mentioned, and that goes for any car. The flush is a higher dollar, higher risk upsell which does not benefit the consumer.

 

I would recommend a "flush", if the fluid has been contaminated, say with accidental addition of motor oil.

You infer there's a "machine" involved in a flush. That may be the case with some transmissions, some auto manufacturers. All I know other than our current Prius is Honda, and their shop manual definition of a "flush" is simply multiple fluid changes, typically three changes, with a short drive after each to homogenize the fluid. It's incredibly wasteful use of pricey fluid, best reserved for contamination cases only.

Also, as is often happens, a somewhat erroneous expression can gain popularity, and even though it's not technically accurate, it becomes accepted, and everyone just "does the translation". I think "transmission flush" is one of those, likely popularized by service writers, when in fact all they're selling is a "drain and fill", which is all that needs doing anyway, in particular with the Prius transaxle.

 

The flush machine is the most efficient way of performing a flush, its simply a glass cylinder with gallons of transmission fluid separated by a small piston seal. One end of the cylinder with new fluid is connected to the incoming transmission fluid line, and the old fluid is expelled into the opposite side of the cylinder, forcing new fluid into the incoming line at an equivalent rate. This can also be done by plugging compressed air into the flush machine. You can see the old fluid come out during the process, and it is considered complete once the old fluid appears as consistent as new fluid does. 5 minute job at a top dollar rate.

To perform a flush through multiple drain and fills is extremely labor intensive. Unless they are assuming you will never check the fluid to verify its condition, it takes time to drain, replug, refill, and cycle the fluid and repeat this process 3 or 4 times until the fluid is entirely new. It is best to do single drain and fills on short intervals. I did this at 15k intervals on previous cars which takes about one gallon to refill, and the transmissions would outlast the car.

 

I would like you to explain how can coolant change in inverter could instantly increase MPG cause for me it make absolutely no sense?

 

Not sure who you're responding too? We're talking about transaxle fluid change, not coolant.