Can driving in neutral damage transmission?
 

Hello everyone. I have an automatic 2008 Scion xD named Bob that I love very much. I've been "hypermiling" with him for months now, getting his rated 26 city/32 hwy up to a combined average of 35-36 mpg. Besides driving slower (which kills me...but I'm doing it) one of the main things I do is throw the car into neutral as much as possible. I was just talking to a mechanic at Toyota/Scion and he was a little concerned that what I'm doing might wear out my neutral gear sooner than it should. Is that possible? I do not want to do anything that might harm Bob's transmission.

Thank you,
Atheria

Check and see what the owner's manual says about towing it. If it wants you to be on a flatbed, stop doing it.

im not an expert, but as long as the engine is running, there should be no problems as the pump is still lubricating the gears.

you may have to do some digging, but after searching for my car i discovered that it has a different shift schedule for neutral depending on speed. like, above 8mph it idles at 1000-1200rpm and won't actuate certain solenoids until the speed is below 8mph.

Towing
 

UH OH. It says it should not be towed with all 4 wheels on the ground. I pray I have not damaged anything! I've been doing what I've been doing for months! Thank you for the information. Now I'm wondering if I should pay the $150 fee to have Toyota take a look at my transmission while it's still under warranty for a few weeks "just in case".

Atheria

My Dodge in Neutral idles between 500-600rpms in Drive it Idles 1000-1200rpms.

My Dodge really isn't supposed to be "flat towed" but I coast in neutral all the time and even with the engine off, no issues. (Deep in the manual even though dodge strongly discourages flat tow it does admit up to 25mph for 10miles)

But then again my low mileage clean and perfect Dodge is worth the salvage value only so I don't care if I destroy the thing since I can't sell it.

That said, YES your transmission may wear slightly faster (make more heat) if your idle speed changes in neutral versus in gear because the pump is pumping more slowly.

Thing is, this is over such a short distance and the temperature gain is so small unless Toyo purposely did something nefarious I can see no way that it will lead to a statistically significant increase in failure rate.

Cheers
Ryan

Solenoids?
 

I don't even know what a solenoid is. :-) I was reading the 109 tips just now and do see that it's BAD to turn a car off and coast if it's an automatic transmission, but my engine is indeed on when I coast in neutral. That might be my saving grace. All I need is to get an extra 5 mpg by trashing my transmission...ugh.

Thank you,
Atheria

Ummm.....I coast A LOT.
 

Hi Ryan,

When I pressed the mechanic and said, "Well, if I'm using neutral more, aren't I also SAVING the other gears by not using them as much?" And he said that was true. He didn't seem OVERLY concerned about what I've been doing and said the transmission should last 150-200,000 miles, but I am a bit "nervousy" and don't want to jeopardize anything. The thing is, I coast a lot. I sometimes coast at 65 mph on the freeway. I don't just coast to stop signs. I can go a mile at a time in neutral if the street is slightly downhill. You did make me feel a little better though.

Thank you,
Atheria

I wouldn't bother, or even worry. Toyota's a fine manufacturer and you've only been doing this for a short time. Worst case, maybe there's a little more wear on some of the innards than there otherwise would be. Maybe someday you'll need an overhaul somewhat sooner than otherwise.

Note- I'm not a tech, or an expert on what exactly gets damaged by running in neutral.

Neutral gear? If it is in neutral it is not in gear. You will be fine as long as the car if running when rolling in neutral as the engine keeps trans fluid pumping. If the car is off trans fluid does not flow and then parts get hot and issues can start. RVs will flat tow cars that do not allow it by adding a transmission fluid pump to keep the parts that are moving with the wheels lubed.

As others have already stated, I don't think it will damage the transmission as long as the engine is running and pumping fluid.