tawm

I wonder if anyone else notices that the RX350 AWD transmission seems to cause deceleration when releasing the accelerator -- until speeds below 21-22 mph when it kicks into a gear that enables easier coasting. My other cars (Volvo RWD and Honda FWD sedans) coast upon releasing the accelerator without such noticeable transmission impedance. The RX350 decelerates while coasting much more quickly -- and it seems to be caused by the transmission. Is this a function of the AWD? Is it adjustable ? My goal is to enable better mpg, i.e. when coasting to a red light down the road?
Thanks for any thoughts.

salimshah

Tawm:

To confirm your hunch, shift into "N" as you coast [Please do so with caution ... some states require that engine is engaged all the times].

SUV has larger profile, so you can not compare their behaviour with other vehicles

Salim

jfelbab

I've noticed this occasionally at low speeds. I never feel it at highway speed but if I remove my foot from the accelerator at about 25 -30 mph I can feel it slowing more than just coasting. It seems to change gear around 20 mph then it coasts normally again.

tawm

Thanks Salim, yes I tested it today and in N(eutral) it coasted much better. So it appears to me that the transmission gearing causes deceleration above 23-25 mph.

flipside909

This occurence was common in our 05 RX330 and even our 08 RX350, both FWD.

Dinomon

There's a TSBI for this: EG007-04 Drone & Vibration on Acceleration

Good Luck.

The G Man

tawn, it does have something to do with the fact that you have full time 4WD. The drive train will drag more when you try to coast.

flipside909

What does this TSIB have to do with decelleration in top gear?

The G Man

Nothing

tawm

OK thanks G Man, and all for your replies. The strange thing is that the RX seems to coast just fine -- once it gets below the low 20s mph. But I guess its heavier weight and 4WD all add up.

The G Man

If your RX coast fine below 20 MPH, It may be a good idea to test drive another RX AWD and see if it does the same. From my experience, permanent 4WD usually dont coast as well as 2WD.

salimshah

There will be drag, the issue is how much is normal and how much is excessive?

Salim