2024 Prius with or without AWD?

I can see the wisdom in that.

On the current Prius, or at least the low spec version, traction control turns off with a simple press of a large and accessible button, but it's more an "off for a moment" button than a true off button. You know it's activated and working because the function display left of the speedo is replaced with a notice that you've turned off TC.

One can almost hear the echo of a parent telling you to stop horsing around in church.

 

Looks like our OP made a decision to AWD.

FWIW...
If I live in a snow zone...AWD.
Costs... only tire replacement would be on the decision tree and also the loss of MPG.
Yet, as I desire to see a GR Prius, I am swayed to AWD even in a sun belt area

 

Tires for the AWD would cost more?

 

The tires themselves won't cost more. There is a slight chance that they'll wear faster than on the FWD model, but I believe that will mostly come down to driving style. Drive in a manner that has power going to the all the wheels more often, and wear could increase.

A higher lump sum for replacement will have an impact on budgeting. With FWD, a person could choose to pay to replace just two tires at a time. It is more strongly recommended to replace all the tires at once on an AWD car. With the Prius's electric system, it isn't a must like some mechanical systems, but there is a chance of two new tires with two worn ones can lead to error codes in the ABS, TRC, and VSC systems.

 

I wouldn't disagree that driving style would be determinative in tire wear.

I'll express my hope, and claim it isn't anything more than a stray thought. Part of the reason AWD was interesting to me is that it effectively cuts torque to the front wheels when accelerating at low speeds. Front wheel spin and plow doesn't only contribute to front tire wear; it also ruins handling.

AWD would involve a lubrication/service cost at some point.


My initial observation about the impact of driving style on general efficiency is that this car is less sensitive. The two liter Corolla with a manual had efficiency falling off a cliff at sustained speeds above 80mph. Worst was a VW with a turbo; it could be a very efficient engine even at higher speeds so long as the turbo wasn't engaged much. Unfortunately, it was enough fun that no one with an inner child could resist its lure.

Brisk acceleration in the Prius seems like a charging opportunity for the battery that makes the engine switch off sooner or longer. There's no free lunch, but this seems like a cheap lunch.

 

Regarding tire wear, the question is does that result in the same or more overall wear? Assuming the tires get rotated.

That would be around the same time as doing the transaxle. It could be years for some owners to reach that point. The fuel costs will be the main difference in running costs.

My Sonic had the turbo. Avoiding having fun was an issue. I believe the low end torque of the turbo did allow more efficient hill climbing.

Pulse and coasting can cheapen the cost for many car types. Car engines are oversized for steady cruising at the speeds mostly driven. They are more thermally efficient under harder acceleration. So accelerating and then coasting can lead to less over all fuel use than steady cruising over the same distance.

A hybrid come do it better by running the engine at the thermal efficiency peak, instead of near it, and charging the battery with the output not needed for the current acceleration event.

 

To clarify... AWD typically it is recommended to replace tires as a set (both fronts or both rears or if one got damage (or worst case all 4) based on circumference changes from wear.

 

It's the same fluid as the front transaxle and you do it at the same time. Around 6y/60k miles, give or take a year/10k. The big annoyance is that, if you do it yourself, you have to buy two jugs of oil instead of one(currently about $62/jug, or $50/jug if you wait for a 20% off sale).

The front transaxle takes 3.7L of fluid and the rear takes 1.4L. The fluid comes in 4L jugs, so someone doing an AWD is going to be left with 3/4 of a jug left over. And since you don't really want to use fluid that's been left in an opened container for 6 years, you're probably just going to end up adding that fresh fluid to the used fluid when heading to the oil recyclers.

 

This tip worked.

I can see using it to play out Walter Mitty fantasies of a finnish rally driver in heavy snow, but not much else.

 

For 5th Gen the transaxle fluid is revised IIRC? For previous gens with the ATF WS fluid, I found a Toyota document that empathically instructs to only use fluid from freshly opened bottles. Wouldn’t hurt to stick to same policy, unless hearing else wise.

you mention “jugs”; 4 quarts? The ATF WS sold up here (Canada) was typically liters, about $10~12 CDN per.

 

Yes, it's a new fluid for gen5(as well as other modern Toyota hybrids). As far as I can tell, it's currently only sold in 4L jugs.

Toyota Ev Transaxel Fluid
(yes, they spelled transaxle incorrectly)

 

Once the bottle is opened and the fluid in the car for several months, it seems it wouldn't be freshly opened at that point either.

<--- Possesses no mechanical expertise

 

Take it up with Toyota lol.

 

The problem is oxygen. Once pretty much any oil is exposed to fresh oxygen, it begins to (very slowly) break down. Once the oil is in the transaxle and sealed up, it interacts with the small amount of fresh oxygen in the transaxle, then that part of the process stops once the free oxygen is used up.

On the flip side, a partially emptied jug of oil has a much higher surface area to mass ratio and has a lot more fresh oxygen to interact with. Additionally, the seal made by the cap is not perfectly air tight, so a very small amount of fresh oxygen can migrate into the container over time. A week or three is no problem as long as the container isn't reopened multiple times(adding a large amount of fresh oxygen each time), but leaving it on the shelf for years and then using it wouldn't be a great idea.

And remember the time portion of the time/distance replacement schedule. When you get right down to it, the time parameter is based off of when the seal is broken on the container, not when it goes in the vehicle.

This also applies to engine oil. Keeping the leftovers of an opened quart/liter of oil on hand isn't a bad idea for little lubrication things(coating something you don't want to rust, using as assembly lube for a small project, etc.), but you don't want to use it in an engine once it's a few weeks old.

 

Again, this edict was for ATF WS, not sure about the new stuff. But might be.

 

Makes sense. I keep synthetic engine oil around for other uses that are much less demanding than engines or transmissions. I could probably repurpose transmission fluid as a solvent/cleaner.

 

These are electric AWD. My 2004 Toyota Hybrid Alphard campervan has the same system called E-Four. No need to change all four tyres at the same time as it has no connection between the rear differential and the front, tho I am not saying that it's not a good idea. So no transfer case to cause lockup or anything like that as in traditional AWD/4wd systems. All electric/software driven. When the front looses traction the rear kicks in and the traction of the rear are independently controlled from the front. Traction control and VSC control the rear. Been tested in mud, snow, ice and on sand - got stuck too one time.