Yes, that's a Chieftain, although it appears that the turret was somehow modified. Chieftain had a gap between the second and third roadwheel, and that cast turret.
When I was a kid, and we played out Warsaw Pact attacks on the Central Front, the Chieftain was the big bugaboo of the WP forces (usually me and my T62s!). It had this amazing rep of being so heavily armored.
A few months ago I saw pictures of a Chieftain in Iraq (captured from the Kuwaitis or the Iranians?), and it had been destroyed by American fire. Fire from the Bushmaster of a Bradley, that is. The 25 chewed right through the turret armor. I was amazed.