GR Yaris GR Yaris Achilles heel ( Transfer case )

[speeddemon666]

It's also a shame some are getting personally offended that you've suggested their precious GRY isn't perfect. I hope this hasn't put you off making these sort of posts in future.

'If my grandmother had wheels, she would have been a bike!'
Gino D'Acampo

 

[Onehp]

Also rrm

We’re not offended that the GRY is not perfect. I could point out many flaws that we all probably share but to try and blame the manufacturer for flaws when used far outside its design is crazy.

Also remember the price point. The GR Yaris mk1 was, when launched, almost half price of a EVO 6 when adjusted for inflation. For a very similar performance.

 

[Diyman25]

We’re not offended that the GRY is not perfect. I could point out many flaws that we all probably share but to try and blame the manufacturer for flaws when used far outside its design is crazy.

The transfer case design is worse then old school Celica GT four and EVO
Whole drivetrain is from RAV4

 

[Diyman25]

Thanks @Diyman25, I for one appreciate knowing about the failures you've found. Always good to hear when things are letting go and why!

170c does seem a bit hot and its a shame the GRMN undertray doesn't help.

It's also a shame some are getting personally offended that you've suggested their precious GRY isn't perfect. I hope this hasn't put you off making these sort of posts in future.

From day 1 of my GR Yaris ownership
Is about track
What I point out is all the possible issue if u are series of track
For people get offended, I really don’t get it

 

[Ecsrobin]

The transfer case design is worse then old school Celica GT four and EVO
Whole drivetrain is from RAV4

I think Toyota were clear on that when selling the car, that the drivetrain was a mash between Yaris and rav4 or similar.

This car is made to a price point and it was quite a low one at that. You are finding where those compromises were made mechanically.

I find your posts interesting to read but there needs to be some understanding on your part that compromises were made for various reasons to ensure a pleasurable experience by the vast majority of owners.

 

[Ecsrobin]

From day 1 of my GR Yaris ownership
Is about track
What I point out is all the possible issue if u are series of track

Just to echo my point above, I think we all find these posts interesting.

 

[SckSqzBngBlo]

my GR Yaris ownership
Is about track

Shame as it is not a track car, it's meant to be a zippy road car.

For track why don't you buy Megane 3. With your budget, you would probably enjoy dominating, not repairing

 

[Sekred]

Shame as it is not a track car, it's meant to be a zippy road car.

For track why don't you buy Megane 3. With your budget, you would probably enjoy dominating, not repairing

Or a 911 GT3

 

[Sekred]

Personally I don't think there is too much wrong with the design of the transfer case.
What's in it. An input shaft from the transmission with a bevel gear bolted to it. An output shaft, (the pinion) with bearings, gaskets and seals. How hard can it be?
It runs hot, probably due to the location behind the engine and below the turbo/dump pipe with not much air flow to cool .

 

[ninjan00dles]

The transfer case runs hot inherently because hypoid gearsets use face friction to transmit power. Not like a bevel gearset which you see in the rear differential. Packaging and airflow don't help - but it will overheat left to its own devices anyways.

The Evo transfer case I believe has 1 quart of fluid so a little bit more thermal capacity, but they still have issues with ACD failing. So it's not like Evo is some sort of perfect mechanical example. The Mazdaspeed 6 and Focus RS both have similar transfer case layouts, but have integrated water-oil heat exchangers from the factory and those are still prone to heatsoak.

I am a bit peeved but at the same time impressed with the Toyota parts binning. The GRY/GRC transfer case was likely originally designed for a part time AWD SUV but with good cooling withstands race conditions to at least around 350 ft*lbs (475 Nm) torque pretty well.

I asked about DIYman's tcase leak origin because I suspect he substantially weakened either the Tcase halves RTV or the tailshaft seal as he raced that car significantly before adding the transfer case cooler. If he actually damaged the hypoid gearset, that is a bit more impressive

 

[Sekred]

When I say Bevel I mean Hypoid which just a spiral bevel gear.
The rear diff is hypoid.

 

[sixtentouge]

I am a bit peeved but at the same time impressed with the Toyota parts binning. The GRY/GRC transfer case was likely originally designed for a part time AWD SUV but with good cooling withstands race conditions to at least around 350 ft*lbs (475 Nm) torque pretty well.

The Lamspeed drag GR Yaris just went into the 8s and makes over 1,000hp. He said they're still using the stock transfer. Developing an oil leak from overheating it (likely cooking a seal or FIPG) or destroying the gears from way overheating the oil in track use, because you didn't install an oil cooler, doesn't make the transfer inadequate, nor weak.

 

[Sekred]

Stock pistons ??

 

[Diyman25]

One of few Taiwan GR Corolla transfer case crack at drag strip
And the peace of gear or case fly off broke the engine block

 

[ninjan00dles]

GR Corolla? So this isn’t your car?
Was the TCase cooled, power level etc

Engine block damage is a tough find

 

[Diyman25]

GR Corolla? So this isn’t your car?
Was the TCase cooled, power level etc

Engine block damage is a tough find

Not my car
Uncool Transfer

 

[GRavy_Baby]

Diyman25, breaking sh*t so you don’t have to since 2023! Really interesting to see you & associates pushing the limits into the unknown with this platform

 

[Boosted8]

I guess this is the addressable market for the billet transfer cases Lamspeed makes.