AWD tire replacement
I have a 2012 Kizashi all wheel drive , automatic transmission, with 235 45 18 tires. A Suzuki dealer's technician told me I must replace all 4 tires at the same time because a difference in tread height from front to rear could ruin a sensor in the rear differential and cost me $1,200. A sensor does not fail under these circumstances, unless it was mechanically tied to the sensor on the other end of the vehicle. And, if it's only reading, what is the purpose of having the sensor if you're not "writing"/ controlling actual speed from front to rear, for instance. Please give me a correct technical explanation of this because the dealer could not.
The only AWD sensor that may be in the rear driveline I'm aware of (other than the wheel speed sensors or non-related TPMS sensors ) would be one for monitoring temperature of the viscous coupler attached to the input of the rear differential. SX4's have one for sure and seeing how it's a very similar setup, the Kiz may have one also. I can't say if it does for sure. Either way the sensor itself wouldn't be damaged.
What the tech may be referring to is the viscous coupler over-heating because the rear driveline (output side of viscous coupler) would be rotating faster or slower than the input side of the coupler, thus possibly causing damage to it due to heat. That would be an expensive proposition. Damaging a sensor? I don't think so. That'll happen when the 'professionals' get in there and start ripping and tearing.
What the tech may be referring to is the viscous coupler over-heating because the rear driveline (output side of viscous coupler) would be rotating faster or slower than the input side of the coupler, thus possibly causing damage to it due to heat. That would be an expensive proposition. Damaging a sensor? I don't think so. That'll happen when the 'professionals' get in there and start ripping and tearing.
Ron
2010 Kizashi GTS, CVT, iAWD (3/10 build date)
2011 SX4 Premium Hatch, CVT, iAWD (12/10 build date)
2018 Mazda CX-5 iAWD Touring
2014 Wrangler JKUW (GONE, traded
)
1991 Samurai, 5-Speed, EFI, Soft-Top (
sold)
2010 Kizashi GTS, CVT, iAWD (3/10 build date)
2011 SX4 Premium Hatch, CVT, iAWD (12/10 build date)
2018 Mazda CX-5 iAWD Touring
2014 Wrangler JKUW (GONE, traded
) 1991 Samurai, 5-Speed, EFI, Soft-Top (
sold)
Like Ronzuki said, it's not the sensor that gets damaged. It's the mechanical components of the AWD system that get damaged over time from the difference in the wheel's (including tire) size. This is why it's advised to replace all four tires at the same time for any AWD vehicle and ideally have all four be of the same tire (brand, model, size, and condition) unless the OE set-up was different (in terms of size).
Having all four of the same tires also makes tire rotations optimal for AWD vehicles, prolonging tire service life.
Having all four of the same tires also makes tire rotations optimal for AWD vehicles, prolonging tire service life.
2025 Mazda CX-50 Preferred Hybrid
2011 Suzuki Kizashi Sport GTS 6MT (Sold)
2011 Suzuki Kizashi Sport GTS 6MT (Sold)
"From the owner's manual: For intelligent All Wheel Drive (i-AWD) models, replacing a tire with one of a different size, or using different brands among the four tires can result in damage to the drive train."
Nothing I could find about replacing all at the same time if one needs to be replaced.
Nothing I could find about replacing all at the same time if one needs to be replaced.
It's because of the impact wear has on the tire, including the diameter and circumference of the tire over time. As you can imagine, a worn tire will have a different physical size and traction characteristics from a new tire of the same type hence will essentially function somewhat like a tire of a different size and brand. Much like it's bad to mix different brands and sizes on AWD systems, the same goes for the same tires but in varying conditions.LPSISRL wrote:"From the owner's manual: For intelligent All Wheel Drive (i-AWD) models, replacing a tire with one of a different size, or using different brands among the four tires can result in damage to the drive train."
Nothing I could find about replacing all at the same time if one needs to be replaced.
This is why it's advised that you try to find a replacement tire of the same type in a similar condition to the rest or even better, replace all four tires together.
2025 Mazda CX-50 Preferred Hybrid
2011 Suzuki Kizashi Sport GTS 6MT (Sold)
2011 Suzuki Kizashi Sport GTS 6MT (Sold)
Question here: Let's say that you have one worn and one new rear tire. They are rotating at different speeds due to the circumference difference. Would not the differential accommodate that just like it does when there is a rotation difference when turning? Would not the same thing happen with the front? It seems that simply turning is going to put all 4 tires at different rotation speeds. The sharper you turn, the bigger the difference. I understand what happens when you have the type of 4 wheel drive that locks the front and rear. You're not even supposed to drive those on dry pavement for any length of time. But with the iAWD, it seems the fluid clutches and everything would minimize any effect that a worn tire cause. You only lose about 2% circumference between brand new and worn out tires. See this link for the technical explanation which I found interesting.
https://mechanics.stackexchange.com/que ... meter-accu
So, is a 2% difference in rotation speed enough to overheat the fluid clutches?
https://mechanics.stackexchange.com/que ... meter-accu
So, is a 2% difference in rotation speed enough to overheat the fluid clutches?