Ihave always heard and have been under the impression that all Merkava III were used by the 188th Brigade, with possible exception of ones used in training by the 460th. The pick below has some marking I’m not familiar with. Looks like a red maple leaf (Canada!!)
Anyone have insight?
In regular service, you’re spot on. The 188th were the frontline\operational unit, and the 460th had them for the purpose of training. The 460th deploy for combat operations in ‘emergency’ situations.
Other than that there are reserve units of course. When newer vehicles are made, they replace older ones, which transfer to reserves. Only reserve units have red brigade markings.
What unit is this? No idea! 
Lucky crew (hole from AT weapon near smoke granades pod)
Did some very limited research, possibly none of it useful
This picture is (as is said when you hover on it) near Lebanon, from 6th of July, 2006, so just days from the second Lebanon War
At that time, the 7th, 188th, and 401st armor brigades were active. Since it wasn’t yet a time of war, it’s unlikely the 460th had any presence in the area.
At the time, only the 188th was operating Merkava Mark 3’s
And, as we know, this is the symbol of the 188th Brigade (my beloved):
So, my guess?
A reserve tank that used to belong to one of the now-defunct former armored brigades, the ones with very little information on them:
At least I have some better understanding. So while regular brigades would be using Mk 2 and 4 it might be possible for reserve brigades to use Mk 3s if they were retired from the 188th
I hadn’t even noticed that hole in the turret! Might be why the poor reserves get this tank 
Back in the day the 7th used Mk.2 and 401st used Mk.4. 460th, as it is training for all the corps., had all kinds obviously.
Nowadays all regulars use Mk.4.
