diff --git a/retrofit-converters/guava/src/test/java/retrofit/converter/guava/AlwaysNullConverterFactory.java b/retrofit-converters/guava/src/test/java/retrofit/converter/guava/AlwaysNullConverterFactory.java
index 92325230143fef59c21080ed686ceabb1e315a1c..5ef6abfaa374fac8793e772f62e4501597a783f2 100644
--- a/retrofit-converters/guava/src/test/java/retrofit/converter/guava/AlwaysNullConverterFactory.java
+++ b/retrofit-converters/guava/src/test/java/retrofit/converter/guava/AlwaysNullConverterFactory.java
@@ -15,7 +15,6 @@
  */
 package retrofit.converter.guava;
 
-import java.io.IOException;
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Type;
 import okhttp3.ResponseBody;
@@ -27,7 +26,7 @@ final class AlwaysNullConverterFactory extends Converter.Factory {
   public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations,
       Retrofit retrofit) {
     return new Converter<ResponseBody, Object>() {
-      @Override public Object convert(ResponseBody value) throws IOException {
+      @Override public Object convert(ResponseBody value) {
         return null;
       }
     };
diff --git a/retrofit-converters/java8/src/test/java/retrofit/converter/java8/AlwaysNullConverterFactory.java b/retrofit-converters/java8/src/test/java/retrofit/converter/java8/AlwaysNullConverterFactory.java
index 006b9062489b8d6385ab1512550e4c26021dcb97..b94d5fd78f77889b61cf57704a8d67367883a208 100644
--- a/retrofit-converters/java8/src/test/java/retrofit/converter/java8/AlwaysNullConverterFactory.java
+++ b/retrofit-converters/java8/src/test/java/retrofit/converter/java8/AlwaysNullConverterFactory.java
@@ -15,7 +15,6 @@
  */
 package retrofit.converter.java8;
 
-import java.io.IOException;
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Type;
 import okhttp3.ResponseBody;
@@ -27,7 +26,7 @@ final class AlwaysNullConverterFactory extends Converter.Factory {
   public Converter<ResponseBody, ?> responseBodyConverter(Type type, Annotation[] annotations,
       Retrofit retrofit) {
     return new Converter<ResponseBody, Object>() {
-      @Override public Object convert(ResponseBody value) throws IOException {
+      @Override public Object convert(ResponseBody value) {
         return null;
       }
     };
diff --git a/retrofit-converters/simplexml/src/main/java/retrofit2/converter/simplexml/SimpleXmlRequestBodyConverter.java b/retrofit-converters/simplexml/src/main/java/retrofit2/converter/simplexml/SimpleXmlRequestBodyConverter.java
index 06aeee1e62c717e42418733e21f0620fe04712de..cb1c9dcb769343217036fa9360e3b6b61b8b82c5 100644
--- a/retrofit-converters/simplexml/src/main/java/retrofit2/converter/simplexml/SimpleXmlRequestBodyConverter.java
+++ b/retrofit-converters/simplexml/src/main/java/retrofit2/converter/simplexml/SimpleXmlRequestBodyConverter.java
@@ -39,6 +39,8 @@ final class SimpleXmlRequestBodyConverter<T> implements Converter<T, RequestBody
       OutputStreamWriter osw = new OutputStreamWriter(buffer.outputStream(), CHARSET);
       serializer.write(value, osw);
       osw.flush();
+    } catch (RuntimeException | IOException e) {
+      throw e;
     } catch (Exception e) {
       throw new RuntimeException(e);
     }