diff --git a/pkg/api/validation/BUILD b/pkg/api/validation/BUILD
index c0b1cbd948..8107e7f45d 100644
--- a/pkg/api/validation/BUILD
+++ b/pkg/api/validation/BUILD
@@ -32,6 +32,7 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1/validation:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/labels:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/diff:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/intstr:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/validation:go_default_library",
diff --git a/pkg/api/validation/validation.go b/pkg/api/validation/validation.go
index 1384830ec3..85b6b82e16 100644
--- a/pkg/api/validation/validation.go
+++ b/pkg/api/validation/validation.go
@@ -38,6 +38,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	unversionedvalidation "k8s.io/apimachinery/pkg/apis/meta/v1/validation"
 	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/util/diff"
 	"k8s.io/apimachinery/pkg/util/intstr"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/validation"
@@ -2734,8 +2735,10 @@ func ValidatePodUpdate(newPod, oldPod *api.Pod) field.ErrorList {
 	allErrs = append(allErrs, validateOnlyAddedTolerations(newPod.Spec.Tolerations, oldPod.Spec.Tolerations, specPath.Child("tolerations"))...)
 
 	if !apiequality.Semantic.DeepEqual(mungedPod.Spec, oldPod.Spec) {
+		// This diff isn't perfect, but it's a helluva lot better an "I'm not going to tell you what the difference is".
 		//TODO: Pinpoint the specific field that causes the invalid error after we have strategic merge diff
-		allErrs = append(allErrs, field.Forbidden(specPath, "pod updates may not change fields other than `spec.containers[*].image`, `spec.initContainers[*].image`, `spec.activeDeadlineSeconds` or `spec.tolerations` (only additions to existing tolerations)"))
+		specDiff := diff.ObjectDiff(mungedPod.Spec, oldPod.Spec)
+		allErrs = append(allErrs, field.Forbidden(specPath, fmt.Sprintf("pod updates may not change fields other than `spec.containers[*].image`, `spec.initContainers[*].image`, `spec.activeDeadlineSeconds` or `spec.tolerations` (only additions to existing tolerations)\n%v", specDiff)))
 	}
 
 	return allErrs