I finally tested DAC yesterday. It performed well (it was only 10-15 degree paved downhill), but it was making a lot of loud clicking noise. I thought that DAC works by slowing down using engine and transition, but then were noise is coming from? Or is it working by using brakes?

Thanks,

Vadim

 

It uses the ABS

 

Then noise makes sense. But if it uses ABS, wouldn't it increase chance of the the spinout?

 

No, ABS pulses the brakes, so their is less of a chance of spin out

 

Exactly, so if computer would be in control when to pulse the brake, it would be higher chance for spin out then if I would be in control, right? Plus pulsing itself, give pulsating force on the downhill, which is not exactly what you want.

 

An apples to orange comparison, but interesting nonetheless, IMO... Last year I had drive down a steep, twisty snow-covered hill in my manual BMW 325Ci... RWD, no DAC, just Directional Stability Control (DSC)...

I put in in second and began rolling down the hill... as I turned into the first corner, the rear end started to step out, but I avoided the urge to hit the brakes and let the DSC handle it... making some very radical noises, my DSC controlled throttle and braking, and allowed me to ski the car down the hill... it was very creepy not to touch the brakes (especially as there was a drop off at the edge of the road, and no guard rail)... the system performed flawlessly, bringing the car back in line each time it started to get out of control... If Lexus's system is anywhere near as good, I'm sure it will work just fine...

 

It pulsates and holds

 

It is manual RWD....(but you know that ). I've driven Supra (manual, RWD, not even ABS back then) for 10 years in Midwest (Wisconsin, Chicago, Michigan) . I was able to handle snow using the transmission in most of the cases. TORSEN differential also saved me number of times in Supra (one of the reasons I've chosen GX).

I don't want to use brakes on downhill, so I am trying to figure out strategy to use. Downshifting my transmission to 2nd actually worked nicely.

 

If you're going down something steep enough where you need DAC, just use
4lo in 1st or 2nd gear as an alternative

 

Yep, but what is use of DAC then?