andyjeffries

As a precursor - I have very little idea of diffs, but I remember reading that the engine in at least the 3.0 TDI is mounted at 90 degrees to the normal and then was reading this "introduction to Quattro" type article and it starts talking about the diffs used in this rotated mounted engines and I thought it might be of interest/relevance.

https://www.carwow.co.uk/blog/audi-q...stem-explained

Don Keener

All Q5 engines are 'longitudinal', also called 'north-south'. The Q3, TT and I believe the A3 are 'transverse' also called 'east-west'. The transverse engines use the Haldex system and the longitudinal use torsen or crown gear systems.

bigpuns

I emailed Audi and they said it's a torsen diff. The chap is even emailing the factory to find out which gen it is. Helpful.

bigpuns

Got this reply from Audi:

"I have received the following response from our Technical Support Team.

Anything with a longitudinally mounted engine uses a Torsen system (Audi A4 upwards); however, we no longer refer to it as
Torsen. Its official name is a Self-locking Centre Differential with Asymmetric Distribution of Torque – Torsen is an older
generation system. Our quattro system is now far more advanced.

To answer the question, the new Audi Q5 (and other MLB products) do not use the Crown Gear system, unless it’s an Audi RS 5.
Technical Support recommends you book a test drive, as the quattro system is hugely capable and something you should experience
first-hand, especially if it is raining or there are wet leaves on the road. You will experience an immediate benefit over cars
with only two driven wheels.

This system splits torque 60 per cent rear and 40 per cent front by default in normal conditions for better driving dynamics,
but then up to 85 per cent of the power can be sent to the rears if it detects wheel-spin at the front. There is also an option
(standard in some higher-powered models - please refer to the price list for this) of a Rear Sports Differential. This is for
Torsen cars and it effectively distributes power to the outside rear wheel when cornering. This effectively “drives” the car
round a corner, eliminating under steer – again we would recommend that you book a test drive at your nearest Audi Centre to
experience this technology first hand."

So there we go!

Thanks all for your help,

Puns