scottgolf

i have an 05, and when i go down hills, sometimes i notice it seems like the car has a trans brake, or jake brake. does anybody know about this? I think its cool.

Bon

It's one of the benefits of drive by wire. If you're not on the gas and asking the car to go faster then it shouldn't be speeding up just because it's going down hill. It is pretty neat isn't it.

balfor

if you step on the brake while going downhill, the trans will shift down a gear to help slow the car. It's not a jake brake at that is for diesel engines and create exhaust backpressure to slow a truck. Personally I don't like it, as #1 it makes it less smooth, and #2 it's just another shift on the trans which is not needed. Brakes are cheaper than transmissions.

Bon

The radar cruise does pretty much the same thing: letting off the gas, downshifting and braking as needed. Ten years of enjoyment and nary a problem. It's quite a luxury and one of the reasons I drive a Lexus.

Stu

I don't notice this on my '05 .... is it because I have the "basic" LS430 ?

Bon

The downhill coasting feature is the same in all. Of course, the radar cruise is a UL thing. Actually, you also get some help from the drive-by-wire while going uphill as well. A little extra throttle is added to assist with maintaining the same cruising speed on an incline. It's more subtle but it's there. By the way, if you let off the gas completely while going down a hill then this "feature" will usually kick in depending on the hill. If you add back any throttle then it will release.

toantran99

I don't think so, try going down on a steeper hill.

fergo308

I find that I need to give the brake a quick tap to get the trans to kick down and do the trans-brake thing on hills.
I like the feature. The LS has quite good brakes,but with the speed some people drive,and how fond they are of using their own brakes the entire way down any hill they come to,I like being able to let the trans slow the car for part of the downhill run,and save my own brakes for when I might actually need to stop at the bottom...


Justin...