Questions about car towing and neutral driving

[thecoolnessrune]

Hello everybody. I hear once in a while that people with manual transmissions drive on flat or downhill areas with their vehicle in neutral (which I know is illegal but that's not the point)

So people are going average or above average speeds this way, correct?

At the same time, when I look in towing guides etc, it always shows that an RWD vehicle that is towed on a trailer that only supports the front wheels can only be driven at 35mph in neutral for only a few miles (I think 50?)

My question is, are people damaging their transmissions when they run their vehicle in neutral? Since you're not "supposed" to because of the 35mph limit? Or are the vehicle companies just putting some padding on themselves to avoid lawsuits?

 

[thedarkwolf]

First coasting in neutral isn't only illegal its stupid and wastes more gas then just leaving it in gear. Been gone over at least 50 times this year a lone here.

The reason you can't tow an automatic car with the trans in neutral and the drive wheels on the ground is the trans isn't being lubricated without the engine running. The torque converter in the trans is bolted to the flywheel of the engine and the torque converter in 99% of automatic cars drives the trans pump. Manual cars don't have that problem.

 

[Zenmervolt]

Some manual transmissions can be towed indefinitely at any speed and some cannot.

The reason that some cannot be towed in neutral is that even when in neutral while coasting (which wastes fuel, but we'll not get into that here), the engine is still on and is still turning the input shaft and some models of manual transmission depend upon the input shaft for splash lubrication. When towing in neutral, the engine is off and the input shaft does not spin, which results in sub-standard lubrication of transmission components; hence the restriction.

ZV

 

[Zenmervolt]

Originally posted by: thedarkwolf
Manual cars don't have that problem.

Some do. Not as many, but some.

ZV

 

[thecoolnessrune]

Ok, I understand. Thank you guys. I was just wondering the difference since I notice that some people do it and always wondered why the manuals say you can't.