There are about 2 seasons of Tank Overhaul, 4 episodes each.
First season is much better than the 2nd, as they focus more on actually tearing down and rebuilding the tanks (much like the car version of Overhauling).
The 2nd season has less of that, for example one episode was on the Elefant....I thought awesome, they are going to tear apart and overhaul an Elefant, but no, they basically power washed it and gave it a paint job.....not exactly an overhauling project. The rest of the show was based on comparing the WWII Elefant to a modern day M-109A6 Paladin. Not sure how they could compare them, since the Elefant was a Tank Destroyer, and the Paladin is a self propelled arty gun....used for 2 completely different jobs.
The rest of the season 2 episodes didn't get much better, one which I thought would be interesting was on a BMP 1, and some guy in California restoring it....the whole show was him and his partner arguing about the BMP, him and his wife arguing about where the money was going to come from to restore the BMP and what little work they actually did to it was basically sand blasting the old paint off of it.
After that, I gave up. Season 1 is much better, actual restoring of the vehicles, 2 of the episodes are from a guy on the Isle of Mann, his crew restores a Comet in one episode, and the other he had 2 Shermans, one shot in the rear, one shot in the front, so he cuts them both in half, and welds the good halves back together.
I think the biggest problem with the show, is unlike the car version of Overhauling, it takes more than a week to tear down a tank and put it back together, so likely took a long, long time to film enough footage for one episode.
So in season 2, they cut it down, and did less filming and more fluff (some of it blatantly wrong) to fill the rest of the show.