Diff lock
 

How do you get diff lock, is it only RWD it happens on?

Thanks

I think what happened there was basically on rwd cars if you bang down the gears at high revs,the back briefly locks up.It's just like briefly whipping up the handbrake.
On fwd and 4wd cars it just helps slow down but is a bit harsh on the engine.
You can still get the back out a little on a 4wd car if you do it mid corner.It's just easier to hold than a rwd.

Danny.

If you brake very hard the weight transfers to the front, unloading the rear tyres. If the brakes are balanced so that the rears are doing a lot of work (so that they are almost lock), then when down-shifting you will add some engine braking and this can cause the rears to lock (not completely, but enough to cause problems!)

I see, and could it happen on a AWD car or does the differential setup on a AWD car elimiate this?

Thanks