What is better for your Auto?

[19jacobob93]

I've wondered this for some time, but basically when you pull up to the lights or are stuck in traffic/ idling for some time, is it better for your transmission to put it into Neutral or leave it in Drive?

I thought about this because in some cars I've driven, if left in neutral at the lights the engine shudders and feels strained, almost like when you lift the clutch a bit with the brakes pressed in a manual and it's about to stall. Basically in some cars it doesn't feel healthy.
In my new car and both parents cars it feels fine when left in drive, but which is the better thing to do?

 

[gfh77665]

Definitely leave it in drive.

 

[Rick in PA]

I'm not a transmission expert, but I'll agree with the above reply. Shifting an automatic transmission into drive or reverse engages bands (friction material). Constantly disengaging and engaging those bands would be bad practice. In gear, and at a stop, the transmission fluid is basically "swishing" (that's an engineering term

) around in the torque converter, no significant wear on the transmission but it does load the engine some.

 

[eljefino]

Leave it in drive. If it shakes your motor mounts have subtle issues-- they are calibrated at the factory to not resonate at idle speed.

Escorts are terrible for this shudder once they get some miles.

 

[gman2304]

If it shudders and feels strained then it already has problems. Having said that... I sometimes find myself shifting to neutral if I have a long wait at a drive through in hot weather with the a/c on. Old habits die hard...LOL!

 

[demarpaint]

Originally Posted By: gman2304
If it shudders and feels strained then it already has problems. Having said that... I sometimes find myself shifting to neutral if I have a long wait at a drive through in hot weather with the a/c on. Old habits die hard...LOL!

I do the same thing at drive through widow lines and RR crossings.

 

[brages]

Sitting in Drive, the torque converter is churning and putting heat into the system. Neutral would help the transmission cool.

I don't think the shift from N to D is any more stressful than any other shift the transmission does.

IMO, this is one of those "who knows, who cares?" questions. It's not going to kill or save your transmission either way.

If you're stuck at a train crossing for five minutes, do you want to have your foot on the brake?

Likewise, in the drive-thru line, do you want to hit the guy in front of you if you take your foot off the brake while digging for your wallet?

 

[DBMaster]

Originally Posted By: eljefino
Escorts are terrible for this shudder once they get some miles.


Oh, my, YES! Had a 93 Escort wagon that would rattle my teeth at traffic lights. I could see that others had this problem from the movement of the tail pipe, too. I replaced the motor mounts, even though they appeared fine, to see if that would help. It made the shaking WORSE. Ultimately, that is why we traded the car in. At nine years and 140,000 miles it had been very reliable, but the shaking was horrible.

 

[DBMaster]

Originally Posted By: brages
If you're stuck at a train crossing for five minutes, do you want to have your foot on the brake? Likewise, in the drive-thru line, do you want to hit the guy in front of you if you take your foot off the brake while digging for your wallet?


If it's summer (and hot) I will put the transmission in park in situations like these so I can continue running the A/C. If it's comfortable outside I will just turn off the engine. I can only imagine how much pollution is created annually by cars sitting at idle at drive-throughs.

We sure are a lazy society.

 

[901Memphis]

The extra cycles engaging the forward clutch is more strain than the torque convertor at idle in drive. We hashed this out long ago. If your doing it at every stop that is. I can see how it would be beneficial if you were waiting rarely for a long train or such but any shifts from a non forward gear into drive cause wear.

 

[hsd]

I usually shift into neutral at lights or other long stops and especially in the summer with the AC on. I have done this for 10 years with my 2000 Accord which seem to have more than their share of trans problems. Mine has been trouble free for 174k miles. In the winter with a cold engine and trans, I may leave it in drive to help things warm up faster.

 

[zzyzzx]

Originally Posted By: eljefino
Leave it in drive. If it shakes your motor mounts have subtle issues-- they are calibrated at the factory to not resonate at idle speed.

Escorts are terrible for this shudder once they get some miles.


I drive a 1995 Escort with it's original automatic transmission at almost 222K miles. I am not familiar with this shudder you mention. I do not recall seeing it at http://www.feoa.net either. You might have heard a heat shield rattle, but a lot of cars or all cars do that.

 

[DBMaster]

I am not talking about a rattle you can hear. I am talking about serious vibration in the car that rattles the contents of the glovebox.

Doesn't matter. I don't have the car anymore - since 2001, actually. Perhaps Ford improved it in 1995. My "1993" wagon was purchased in June of 1992.

 

[brages]

Originally Posted By: 901Memphis
any shifts from a non forward gear into drive cause wear.


Any shifts cause wear... I can't see how the shift (at virtually no load) from N into D is going to wear any worse than the shift from 1 to 2 or 2-3, etc.

If anything, normal shifting during driving should cause more wear, since the load is a lot higher and the shift is slipped a bit for driver comfort.

Again, IMO, it's not going to kill or save your transmission either way.

IMO, auto transmissions typically fail from defects in design or manufacture. Fastidious maintenance or gentle driving may help postpone the failure...

 

[jrustles]

I'm known to shift to neutral all the time with autos, even when not sitting at idle

 

[nicholas]

According to my onboard computer - my car uses less gasoline when I am in park or neutral....compared to when in drive.