The wheel slipped based on what the other guys said.
Now to the weight shifts:
If you are braking, either with brakes, or engine breaking, the weight gets transferred to the front (ie. another reason the rear slips so much easier). If you slow down then the weight goes to the front wheel. If you accelerate the weight goes to the back, reguardless of means.
Now to the weight shifts:
If you are braking, either with brakes, or engine breaking, the weight gets transferred to the front (ie. another reason the rear slips so much easier). If you slow down then the weight goes to the front wheel. If you accelerate the weight goes to the back, reguardless of means.