Gar328 -

What matters is what happens inside those four walls.

Garmin no longer manufactures new GAR328 boards, but specialized avionics repair stations (e.g., Bevan Aviation, Duncan Avionics) offer reballing and reflow services. Expect costs between $450–$750 USD for a full GAR328 refurbishment. Owners of experimental aircraft often replace the entire unit with a modern GTN series, but for certified aircraft on a budget, reworking the GAR328 remains a viable option. gar328

Do not confuse the GAR328 with the GAR328A or GAR328B revisions. The “A” revision introduced a reinforced ground plane for helicopter applications, while the “B” revision added DO-160G environmental compliance. All three are physically interchangeable, but firmware mismatches can cause a “No Data” error on the HSI display. What matters is what happens inside those four walls