Maintaining and/or Replacing Your Gas Grill's Lava Rock/Briquette Grates
Courtesy Appliance Factory Parts
Though your briquette grates are probably the last thing you'd ever think you'd need to look at, let alone replace, the fact is that NOT to look at them every year or so (depending on how much you grill) might lead to more repair costs in the future! For example, a broken grate may allow the briquettes or lava rocks to break through and hit the burners, which could damage them and spoil a perfectly good meal! Plus the mess won't be fun to clean up!!
Inspect rock grates periodically
Rock grates are subject to very high temperatures and will weaken and deteriorate over time.
Knock off loose rust and scale with a wire brush.
If grate is very thin, or sags excessively, replace with a new grate sized to your model
About the author: Appliance Factory Parts is a one-stop shop for your grill needs. They have parts for 12,000 BBQ models and 40,000 BBQ parts, including gas grill burners, grids, and grates