IIRC Panzergrenadiers were the mech infantry attached to the armour units. They would drive around in half tracks etc and disembark to give the armour cover.
One thing I do note from my discussions with WWII ppl (English) is that they held the German soldier in high respect. They were good, had the best equipment and were well trained. Certainly at the outbreak of war there wasn't anything quite like them.
As one guy said to me.....
"In 1940 we were fighting guys who had been training for years in camps in the forests. We were just skinny kids."
Steel