diff --git a/test/e2e/generator/generate.go b/test/e2e/generator/generate.go
index 8581d6344..4920dff42 100644
--- a/test/e2e/generator/generate.go
+++ b/test/e2e/generator/generate.go
@@ -24,9 +24,8 @@ var (
 	}
 
 	// The following specify randomly chosen values for testnet nodes.
-	nodeDatabases = uniformChoice{"goleveldb", "cleveldb", "rocksdb", "boltdb", "badgerdb"}
-	// FIXME disabled grpc due to https://github.com/tendermint/tendermint/issues/5439
-	nodeABCIProtocols    = uniformChoice{"unix", "tcp", "builtin"} // "grpc"
+	nodeDatabases        = uniformChoice{"goleveldb", "cleveldb", "rocksdb", "boltdb", "badgerdb"}
+	nodeABCIProtocols    = uniformChoice{"unix", "tcp", "grpc", "builtin"}
 	nodePrivvalProtocols = uniformChoice{"file", "unix", "tcp"}
 	// FIXME disabled v1 due to https://github.com/tendermint/tendermint/issues/5444
 	// FIXME disabled v2 due to https://github.com/tendermint/tendermint/issues/5513
diff --git a/test/e2e/networks/ci.toml b/test/e2e/networks/ci.toml
index 12478ef99..522fb5266 100644
--- a/test/e2e/networks/ci.toml
+++ b/test/e2e/networks/ci.toml
@@ -50,9 +50,7 @@ persist_interval = 0
 [node.validator03]
 seeds = ["seed01"]
 database = "badgerdb"
-# FIXME Should use grpc, but it has race conditions
-# https://github.com/tendermint/tendermint/issues/5439
-abci_protocol = "unix"
+abci_protocol = "grpc"
 privval_protocol = "unix"
 persist_interval = 3
 retain_blocks = 3
@@ -72,9 +70,7 @@ start_at = 1005 # Becomes part of the validator set at 1010
 seeds = ["seed02"]
 database = "cleveldb"
 fast_sync = "v0"
-# FIXME Should use grpc, but it has race conditions
-# https://github.com/tendermint/tendermint/issues/5439
-abci_protocol = "tcp"
+abci_protocol = "grpc"
 privval_protocol = "tcp"
 # FIXME The WAL gets corrupted when killed
 # https://github.com/tendermint/tendermint/issues/5422