First towed test... shaky ...!

[fortow]

This is exactly one of reasons why I did not intend to follow the advice to disconnect the battery while towing.

It was probably given because the factory believed that some owners might tow the car while leaving the key in the 'on' position thus depleting the battery charge. That would possibly be the lesser of the problems as can now be seen.

If the gear shift can move as described with the battery disconnected, then this should be a warranty repair. That may be a problem they're trying to circumvent. Hopefully it will be resolved amicably.

[Pacific Smarty]

I hassled for about 10,000 miles with wheel dance when I'd pull away from curbs or pull out of tight turns before I tried a bungee.

But the bungee is perfect!

The amazing thing is, it takes almost no bungee tension to eliminate wheel dance. I've experimented, and don't get wheel dance with the lightest bungee force I've tried. I was hesitant to try it at all because it looked like some people were binding the steering wheel with a lot of force. As it turns out, a relatively light bungee simply adds enough damping to fix things.

[LewisB]

I've received authorisation to rent a loaner at smart expense - that at least is helpful - while the incident is reviewed in Germany. I also received a VM from a field manager and expect to speak with him tomorrow.
More later.
LewisB

[LewisB]

OK. The good news. Daimler has agreed to replace the ruined engine under warranty. They are even giving consideration to replacing the badly damaged rear tires.
The important news. It appears there is a possibility that the car was not in Neutral when being towed (WAIT before you shout HAH! I thought so) - for the following reason.
Apparently, it is the electronics on the manual gearbox that disconnect the drive in Neutral - but they don't always do so when you move the gear lever. I am now advised to actually look at the gear position display during the afore-mentioned 30 seconds and make sure that "N" is showing - not 3 horizontal bars. Be warned! Check this before towing and avoid my fate.

[fortow]

Originally Posted by LewisB

...Apparently, it is the electronics on the manual gearbox that disconnect the drive in Neutral - but they don't always do so when you move the gear lever. I am now advised to actually look at the gear position display during the afore-mentioned 30 seconds and make sure that "N" is showing - not 3 horizontal bars. Be warned! Check this before towing and avoid my fate.

Good news. The tires should be replaced too since the damage to them was due to the same cause.

Question - do those who disconnect the battery always shift to neutral BEFORE disconnecting the battery? What is the "gear position display" you refer to? - is it the display at the dashboard? Do I understand you correctly in saying that the shift lever indicating the "N" position may not assure that the transmission is in fact in neutral?
This problem then is unrelated to disconnecting the battery or not - is that the case?

[LewisB]

The simplest answer is to post here the label on my visor - suitably amended in light of the new advice to check the dash display when placing the car in neutral:

Not following this sequence may result in disastrous damage

BEFORE TOWING
Set hand (parking) brake
Depress and hold brake pedal
Switch ignition to ON
Move gear lever to N
Check dash display shows N, not ///
Release brake pedal
Turn ignition key left as far as it will go
Wait till dash display goes dark (+- 30 secs)
Turn battery switch to OFF
Release hand (parking) brake
AFTER TOWING
Set hand (parking) brake
Turn battery switch to ON
Move gear lever to P
Switch ignition to OFF
Remove key and lock car OR start engine and drive
IF BATTERY NEEDS TO BE DISCONNECTED FOR OTHER REASONS
Disconnect from Negative lead first Reconnect to Positive lead first
JUMP STARTING
1. Clamp to Positive of charger.
2. Clamp to Positive of Smart.
3. Start engine of charger and run at idle.
4. Clamp to Negative of charger
5. Clamp to Negative of Smart.
6. Start engine of Smart.
7. Remove cables in reverse order.
DO NOT SWITCH ON SMART HEADLIGHTS UNDER ANY
CIRCUMSTANCES UNTIL CABLES ARE REMOVED.
==============================================

so yes, the need to check that the electronics really have moved the transmission to neutral comes before disconnecting the battery, so appears to be unrelated.

[fortow]

Thanks.

Just a few additional comments.
I presume those instructions are yours and posted to be certain that you forget nothing in the future.
For my purposes, I never will set the parking brake again before towing. I once left it on and fortunately another motorhome owner watched as I pulled away and stopped me before any damage occurred. It is too easy to forget that that brake has been set, and under some circumstances it could even be forgotten regardless of whether or not you have those instructions printed out and visible. You may not bother to read one day, be in a hurry or have something else interfere, and not remember that the brake was set - that happened to me.

After the car is hooked up, stepping on the brake pedal is sufficient to move the shift lever to neutral. Watching the displays is mandatory.

You're right that the negative lead on the battery should always be disconnected first and reconnected last to avoid the possibility of accidental short circuits.
I might suggest, however, when jump starting, to connect the negative lead from the charging car to a ground location away from your car's battery.

I still have no intentions of disconnecting the battery while towing, nor do I see any need to do so.

[smartie yank]

Mine is a 450 but I think this would work the same for a 451. I try to hitch up on level ground. Stop the smart a foot or two from the towing vehicle, put in neutral, shut it off and then pull the car forward and drop the coupler on the ball. If it is not in neutral, you can't roll it forward. Again you must be on level ground. Some people with physical limitations may have problems doing it this way but for most it rolls pretty easy.

[Ken Boothe]

fortow:I also left a parking brake set on a geo tracker only one wheel locked up but it was for 4 blocks
and the tire was only 2 days old.Newmar dutch star with 300 cat i couldn't tell any differance with
brake on or off.

[fortow]

Originally Posted by Ken Boothe

...Newmar dutch star with 300 cat i couldn't tell any differance with
brake on or off.

Right, and with the smart you certainly wouldn't know. I felt nothing, but because someone stopped me it was only towed about 50 yards.

If a driver is accustomed to pulling on the 'E' brake then this could easily happen. As far as I'm concerned, making certain that the hand brake is off is equally as important as assuring that the gearshift is in neutral and the ignition key is turned off.

Since those things are a requirement whether the battery is disconnected or not - then why on earth would anyone bother to disconnect the battery? Doing that really doesn't solve any problem at all.