Toyota Prius Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
I'm not sure if this goes in General or Technical, but
Is the Prius all-wheel drive? The website says it has traction control, which I think means it has to be able to power all the wheels. Is that right?
Also, what does Toyota's TRAC do?
 

·
Registered
Joined
·
928 Posts
The Prius is front wheel drive only. The abbreviation TRAC normally stands for Toyota Rent-A-Car, not traction control. The standard traction control simply cuts power to the front wheels when they spin faster than the rear wheels. The optional stability control actively applies or releases braking to individual wheels to stabilize the car through turns and hard braking maneuvers. It relies on solid-state gyros in addition to wheel speed sensors to detect trouble. That's about the extent of my knowledge. Check Toyota's website or get the 2004 New Car Features guide from Toyota to learn more. Or ask more detailed questions and hope someone with more info answers.
 

·
Registered
Joined
·
425 Posts
RSnyder said:
The standard traction control simply cuts power to the front wheels when they spin faster than the rear wheels.
Almost correct :wink:

Traction control applies breaking to the driven wheels to stop a driven wheel from spinning, for exmple on ice. The driven wheel can be rear or (as in the Pruis) front wheel, or in the case of a 4x4 any wheel.
 

·
Registered
Joined
·
928 Posts
Just to be sure, are you saying this in general or specifically about the Prius? It's not true of the 2001-03 model, but maybe the 2004?
 

·
Registered
Joined
·
128 Posts
Victor said:
RSnyder said:
The standard traction control simply cuts power to the front wheels when they spin faster than the rear wheels.
Almost correct :wink:

Traction control applies breaking to the driven wheels to stop a driven wheel from spinning, for exmple on ice. The driven wheel can be rear or (as in the Pruis) front wheel, or in the case of a 4x4 any wheel.
Further clarification. Traction control generally results in a combination of reduced engine power (selective cylinder shut off, spark retard, gear upshifts, or throttle retard) followed by hydraulic brake apply to the driven slipping wheels if needed to slow it to the target slip rate (maximum allowed wheel slip above the actual vehicle speed). It is necessary to allow some slip if the vehicle is accelerating, the same situation where negative slip is needed to achieve efficient antilock braking. This can be done on one or more driven wheels independently if the hydaulic brakes are used. The Pruis is front wheel drive, meaning only the front wheels can accelerate the vehicle through power application, thus traction control is performed only on the front wheels. Also, the Pruis drive system is rather unique, and as such the engine power reduction portion of traction control is partially achieved by reducing electric motor torque through the power split device.
 

·
Registered
Joined
·
319 Posts
RSnyder said:
The abbreviation TRAC normally stands for Toyota Rent-A-Car, not traction control.
I was reading the window sticker for the car, I left it in my glove box. Where it says: Traction Control, right after it, it says: TRAC. So it might stand for both. Go to John's site: http://john1701a.com/index.html and on the left go to Prius Info, and the Window Sticker - N. It shows it there.
 
1 - 7 of 7 Posts
Top