diff --git a/go16.go b/go16.go
index e0061146..6775d23c 100644
--- a/go16.go
+++ b/go16.go
@@ -56,7 +56,7 @@ func toRPCErr(err error) error {
 	case transport.StreamError:
 		return status.Error(e.Code, e.Desc)
 	case transport.ConnectionError:
-		return status.Error(codes.Internal, e.Desc)
+		return status.Error(codes.Unavailable, e.Desc)
 	default:
 		switch err {
 		case context.DeadlineExceeded:
diff --git a/go17.go b/go17.go
index f1e0be2b..66501b0f 100644
--- a/go17.go
+++ b/go17.go
@@ -56,7 +56,7 @@ func toRPCErr(err error) error {
 	case transport.StreamError:
 		return status.Error(e.Code, e.Desc)
 	case transport.ConnectionError:
-		return status.Error(codes.Internal, e.Desc)
+		return status.Error(codes.Unavailable, e.Desc)
 	default:
 		switch err {
 		case context.DeadlineExceeded, netctx.DeadlineExceeded:
diff --git a/rpc_util_test.go b/rpc_util_test.go
index 8004ad2c..7cbad491 100644
--- a/rpc_util_test.go
+++ b/rpc_util_test.go
@@ -148,7 +148,7 @@ func TestToRPCErr(t *testing.T) {
 		errOut error
 	}{
 		{transport.StreamError{Code: codes.Unknown, Desc: ""}, status.Error(codes.Unknown, "")},
-		{transport.ErrConnClosing, status.Error(codes.Internal, transport.ErrConnClosing.Desc)},
+		{transport.ErrConnClosing, status.Error(codes.Unavailable, transport.ErrConnClosing.Desc)},
 	} {
 		err := toRPCErr(test.errIn)
 		if _, ok := status.FromError(err); !ok {