>>96161489
Depends what you consider to be a tank.

Dunecrawlers are deceptively tanky, between their 2+ and 4++. You could give them the eradication beamer or the phosphor cannon to clear infantry, if need be. Disintigrators shoot pretty well.
If you expand the definition a bit, you can include some Kastelans, which are pretty tanky and can do some serious work in melee. Give them an enginseer to follow them around and give one a FNP (honestly, if you're building a tank-heavy Admech list, you should probably have several enginseers dishing out this buff). If you want to expand it further, throw some ironstriders in there for relatively inexpensive units to move around and stand on objectives and lob decent shooting into targets. You'll probably want some ibmnfiltrators or Pteraxii to do secondaries. Your pick of whether you run it as Haloscreed or Cybernetica Cohort, a decision you should make based on the stratagem support (or enhancements, I guess) you want. Personally, I like the flexibility of Haloscreed, but if you like the look of cybernetica better, then just remember that all its strats happen in the command phase.

>>96161511
He meant tank-heavy, not heavy tanks. Also, the dunecrawler stands alone pretty well, but you're right that the shield ability is definitely is a bit squandered if you don't bring some Skittles to stand near it