diff --git a/akka-cluster/src/multi-jvm/scala/akka/cluster/LargeMessageClusterSpec.scala b/akka-cluster/src/multi-jvm/scala/akka/cluster/LargeMessageClusterSpec.scala
index 14d9fe24ec..761c4f313d 100644
--- a/akka-cluster/src/multi-jvm/scala/akka/cluster/LargeMessageClusterSpec.scala
+++ b/akka-cluster/src/multi-jvm/scala/akka/cluster/LargeMessageClusterSpec.scala
@@ -9,13 +9,13 @@ import akka.actor.ActorIdentity
 import akka.actor.ActorRef
 import akka.actor.ExtendedActorSystem
 import akka.actor.Identify
-import akka.actor.PoisonPill
 import akka.cluster.ClusterEvent.UnreachableMember
 import akka.remote.RARP
 import akka.remote.artery.ArterySettings
 import akka.remote.testconductor.RoleName
 import akka.remote.testkit.MultiNodeConfig
 import akka.remote.testkit.MultiNodeSpec
+import akka.serialization.SerializerWithStringManifest
 import akka.testkit._
 import com.typesafe.config.ConfigFactory
 
@@ -27,12 +27,21 @@ object LargeMessageClusterMultiJvmSpec extends MultiNodeConfig {
   // Note that this test uses default configuration,
   // not MultiNodeClusterSpec.clusterConfig
   commonConfig(ConfigFactory.parseString(
-    """
+    s"""
     akka {
-      loglevel = DEBUG
       cluster.debug.verbose-heartbeat-logging = on
       loggers = ["akka.testkit.TestEventListener"]
-      actor.provider = cluster
+
+      actor {
+        provider = cluster
+
+        serializers {
+          test = "akka.cluster.LargeMessageClusterMultiJvmSpec$$SlowSerializer"
+        }
+        serialization-bindings {
+          "akka.cluster.LargeMessageClusterMultiJvmSpec$$Slow" = test
+        }
+      }
 
       testconductor.barrier-timeout = 3 minutes
 
@@ -44,20 +53,29 @@ object LargeMessageClusterMultiJvmSpec extends MultiNodeConfig {
         large-message-destinations = [ "/user/largeEcho", "/system/largeEchoProbe-3" ]
 
         advanced {
-          #maximum-frame-size = 2 MiB
-          #buffer-pool-size = 32
           maximum-large-frame-size = 2 MiB
           large-buffer-pool-size = 32
-
-          compression {
-            #actor-refs.advertisement-interval = 2 second
-            #manifests.advertisement-interval = 2 second
-          }
         }
       }
     }
     """))
 
+  final case class Slow(payload: Array[Byte])
+
+  class SlowSerializer(system: ExtendedActorSystem) extends SerializerWithStringManifest {
+    override def identifier = 999
+    override def manifest(o: AnyRef) = "a"
+    override def toBinary(o: AnyRef) = o match {
+      case Slow(payload) ⇒
+        // simulate slow serialization to not completely overload the machine/network, see issue #24576
+        Thread.sleep(100)
+        payload
+    }
+    override def fromBinary(bytes: Array[Byte], manifest: String) = {
+      Slow(bytes)
+    }
+  }
+
 }
 
 class LargeMessageClusterMultiJvmNode1 extends LargeMessageClusterSpec
@@ -131,17 +149,18 @@ abstract class LargeMessageClusterSpec extends MultiNodeSpec(LargeMessageCluster
 
     "not disturb cluster heartbeat messages when saturated" taggedAs LongRunningTest in {
 
-      // FIXME only enabled for Aeron transport until #24576 is fixed
+      // for non Aeron transport we use the Slow message and SlowSerializer to slow down
+      // to not completely overload the machine/network, see issue #24576
       val arterySettings = ArterySettings(system.settings.config.getConfig("akka.remote.artery"))
-      if (!arterySettings.Enabled || arterySettings.Transport != ArterySettings.AeronUpd)
-        pending
+      val aeronUdpEnabled = (arterySettings.Enabled && arterySettings.Transport == ArterySettings.AeronUpd)
 
       runOn(second) {
         val largeEcho2 = identify(second, "largeEcho")
         val largeEcho3 = identify(third, "largeEcho")
 
         val largeMsgSize = 1 * 1000 * 1000
-        val largeMsg = ("0" * largeMsgSize).getBytes("utf-8")
+        val payload = ("0" * largeMsgSize).getBytes("utf-8")
+        val largeMsg = if (aeronUdpEnabled) payload else Slow(payload)
         (1 to 3).foreach { _ ⇒
           // this will ping-pong between second and third
           largeEcho2.tell(largeMsg, largeEcho3)