Today I had to brake hard and turn the wheel at the same time....While doing so the car appeared to downshift multiple gears and the revs went way high and stayed that way for about 10 seconds, almost as though I had the car in manual mode and downshifted one gear to many. Please let me know if this is normal behavior.

 

That sounds normal especially if you were in DS mode. The engine logic detects the rapid deceleration and uses the engine braking to assist via transmission downshifting, and in DS mode does this more agressively to keep you in the power band for better acceleration i.e. if your driving on curvy/winding roads. As long as it doesn't go into redline (which the logic should never allow) it sounds fine.

 

I wasnt in DS mode, thats the par that worries me. I saw some other threads, maybe this is it?

https://www.myg37.com/forums/g37-sed...wnshift-2.html

 

its okay, its engine breaking, my 04 camry does that too

it shows more if ur rapid decelerating when ur going down hill, once my car automatically hit up to 4-5k RPM when im trying to break going down hill

 

You may be confusing the OP:

Break/breaking = taking time out for coffee
Brake/braking = used to stop a vehicle.

 

I'd say..normal.

I'm well aware of how the tranny operates in my car...espcially DS mode.

However, the other day while driving around 55mph I had to make a panic stop. To my surprise, the car downshifted aggressively to aid in braking. This aggressive downshifting while in D has a dramatically higher threshold than in DS...where its downshifting for fun.

This downshifting is more of the Oh ****e type of braking. I've never had that happen in 10,000 miles of ownership. That was the first panic type stop I made with the car.

 

I believe this is fairly normal.

the ecu is adapting to the conditions. lower gear/higher rpm gives you more traction in this situation. in the case of my car, this happens and my seatbelts pull like hell. I feel very safe in my car... freaked me out the first time.

it's pretty cool how smart it is. for example when you take a corner at a good speed, it knows to downshift and keep the revs high, instead of slowing down when you're hitting the brake.



10 seconds seems like a lot of time tho. I'm pretty sure I'd be able to go from 80-0 in less than 10seconds...