diff --git a/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala b/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala
index 64d9086633..1ad631c449 100644
--- a/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala
+++ b/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala
@@ -13,11 +13,11 @@ class TestTimeSpec extends AkkaSpec(Map("akka.test.timefactor" -> 2.0)) {
 
       val probe = TestProbe()
       val now = System.nanoTime
-      intercept[AssertionError] { probe.awaitCond(false, Duration("1 second")) }
+      intercept[AssertionError] { probe.awaitCond(false, 1.second) }
       val diff = System.nanoTime - now
-      val target = (1000000000l * testKitSettings.TestTimeFactor).toLong
-      diff should be > (target - 500000000l)
-      diff should be < (target + 500000000l)
+      val target = (1000000000L * testKitSettings.TestTimeFactor).toLong
+      diff should be >= target
+      diff should be < (target + 1000000000L) // 1 s margin for GC
     }
 
     "awaitAssert must throw correctly" in {