Gearbox 7g+

[Spider10]

I was asked yesterday how does the gearbox know that i have an lsd fitted in ref with traction control etc
I couldn't answer so i thought id ask on here
Thanks in advance

 

[Spider10]

Sorry c63

 

[markjay]

LSD is an option on the Datacard (471, I think).

Because it's on the Datacard, this means that every ECU on the car that needs to know about it, is aware, and this includes the TCU.

Now, if you're asking what happens if the LSD is retrofitted to a car that didn't have it from the factory, and not SCN-coded to the Datacard, then I don't know the answer... clearly the TCU (or any other ECU on the car) won't know of its existence, but what practical implications it will have on the TCU, ESP, ABS, etc etc - I don't know.

 

[jasonh]

If it's an aftermarket LSD then the gearbox won't but it will still have speed information from both rear wheels so it should be able to do a fairly decent job.

 

[Spider10]

Its a quafe lsd fitted by MSL

 

[markjay]

Its a quafe lsd fitted by MSL

Check on a VIN decoder to see of it was SCN-coded to the Datacard.

If it was, than the transmission will know about it.

 

[Muckypaps]

The gearbox doesn't need to know.

 

[Spider10]

No it didn't have 1 onit to start with thats why i had 1 fitted ,I suppose i should of asked Acid while i was there I do know the gearbox boot was removed .
The car is perfect MSL is the place to go with these i just wounded

 

[Spider10]

The gearbox doesn't need to know.

So how does traction control work then
Genuine question

 

[Muckypaps]

So how does traction control work then
Genuine question

Google it.
It doesn't change gear, it backs off the throttle.
It's a mechanical LSD, not electronic.

 

[Muckypaps]

Education

 

[Spider10]

I know it doesn't change gear im not daft ,i thought (might be wrong ) that when traction kicks in it brakes the wheel with no traction ?

 

[Spider10]

That's not education i know how it works
But what tells the car you have changed the diff to an lsd not an open diff or doesn't it need to know that was the question

 

[Muckypaps]

It doesn't need to know the diff type, it gets it's wheel speed from the individual wheel sensors.
Mine has an LSD, the traction control kicks in when the rear wheels are rotating faster than the front wheels.