diff --git a/oauth2_http/java/com/google/auth/oauth2/OAuth2Credentials.java b/oauth2_http/java/com/google/auth/oauth2/OAuth2Credentials.java
index 94ddeb549..20e1c92e5 100644
--- a/oauth2_http/java/com/google/auth/oauth2/OAuth2Credentials.java
+++ b/oauth2_http/java/com/google/auth/oauth2/OAuth2Credentials.java
@@ -68,8 +68,8 @@
 public class OAuth2Credentials extends Credentials {
 
   private static final long serialVersionUID = 4556936364828217687L;
-  static final Duration DEFAULT_EXPIRATION_MARGIN = Duration.ofMinutes(5);
-  static final Duration DEFAULT_REFRESH_MARGIN = Duration.ofMinutes(6);
+  static final Duration DEFAULT_EXPIRATION_MARGIN = Duration.ofMinutes(3);
+  static final Duration DEFAULT_REFRESH_MARGIN = Duration.ofMinutes(3).plusSeconds(45);
   private static final ImmutableMap<String, List<String>> EMPTY_EXTRA_HEADERS = ImmutableMap.of();
 
   @VisibleForTesting private final Duration expirationMargin;