diff --git a/packages/common-grpc/src/service.js b/packages/common-grpc/src/service.js
index e83e7ffd44f..6d3a114fe7f 100644
--- a/packages/common-grpc/src/service.js
+++ b/packages/common-grpc/src/service.js
@@ -260,7 +260,7 @@ GrpcService.prototype.request = function(protoOpts, reqOpts, callback) {
   }
 
   try {
-    reqOpts = util.decorateRequest(reqOpts, { projectId: this.projectId });
+    reqOpts = this.decorateRequest_(reqOpts);
   } catch(e) {
     callback(e);
     return;
@@ -362,7 +362,7 @@ GrpcService.prototype.requestStream = function(protoOpts, reqOpts) {
   }
 
   try {
-    reqOpts = util.decorateRequest(reqOpts, { projectId: this.projectId });
+    reqOpts = this.decorateRequest_(reqOpts);
   } catch(e) {
     setImmediate(function() {
       stream.destroy(e);
@@ -443,7 +443,7 @@ GrpcService.prototype.requestWritableStream = function(protoOpts, reqOpts) {
   }
 
   try {
-    reqOpts = util.decorateRequest(reqOpts, { projectId: this.projectId });
+    reqOpts = this.decorateRequest_(reqOpts);
   } catch (e) {
     setImmediate(function() {
       stream.destroy(e);
@@ -687,6 +687,22 @@ GrpcService.structToObj_ = function(struct) {
   return convertedObject;
 };
 
+/**
+ * Assign a projectId if one is specified to all request options.
+ *
+ * @param {object} reqOpts - The request options.
+ * @return {object} - The decorated request object.
+ */
+GrpcService.prototype.decorateRequest_ = function(reqOpts) {
+  reqOpts = extend({}, reqOpts);
+
+  delete reqOpts.autoPaginate;
+  delete reqOpts.autoPaginateVal;
+  delete reqOpts.objectMode;
+
+  return util.replaceProjectIdToken(reqOpts, this.projectId);
+};
+
 /**
  * To authorize requests through gRPC, we must get the raw google-auth-library
  * auth client object.
@@ -711,7 +727,7 @@ GrpcService.prototype.getGrpcCredentials_ = function(callback) {
     );
 
     if (!self.projectId || self.projectId === '{{projectId}}') {
-      self.projectId = authClient.projectId;
+      self.projectId = self.authClient.projectId;
     }
 
     callback(null, credentials);
diff --git a/packages/common-grpc/test/service.js b/packages/common-grpc/test/service.js
index a0163723bea..60f9f2690e0 100644
--- a/packages/common-grpc/test/service.js
+++ b/packages/common-grpc/test/service.js
@@ -515,7 +515,7 @@ describe('GrpcService', function() {
 
   describe('request', function() {
     var PROTO_OPTS = { service: 'service', method: 'method', timeout: 3000 };
-    var REQ_OPTS = {};
+    var REQ_OPTS = { reqOpts: true };
     var GRPC_CREDENTIALS = {};
 
     function ProtoService() {}
@@ -747,9 +747,8 @@ describe('GrpcService', function() {
         it('should decorate the request', function(done) {
           var decoratedRequest = {};
 
-          fakeUtil.decorateRequest = function(reqOpts, config) {
-            assert.strictEqual(reqOpts, REQ_OPTS);
-            assert.deepEqual(config, { projectId: grpcService.projectId });
+          grpcService.decorateRequest_ = function(reqOpts) {
+            assert.deepEqual(reqOpts, REQ_OPTS);
             return decoratedRequest;
           };
 
@@ -770,7 +769,7 @@ describe('GrpcService', function() {
         var error = new Error('Error.');
 
         it('should return a thrown error to the callback', function(done) {
-          fakeUtil.decorateRequest = function() {
+          grpcService.decorateRequest_ = function() {
             throw error;
           };
 
@@ -787,7 +786,7 @@ describe('GrpcService', function() {
         grpcService.getService_ = function() {
           return {
             method: function(reqOpts) {
-              assert.strictEqual(reqOpts, REQ_OPTS);
+              assert.deepEqual(reqOpts, REQ_OPTS);
               done();
             }
           };
@@ -1063,9 +1062,8 @@ describe('GrpcService', function() {
         it('should decorate the request', function(done) {
           var decoratedRequest = {};
 
-          fakeUtil.decorateRequest = function(reqOpts, config) {
+          grpcService.decorateRequest_ = function(reqOpts) {
             assert.strictEqual(reqOpts, REQ_OPTS);
-            assert.deepEqual(config, { projectId: grpcService.projectId });
             return decoratedRequest;
           };
 
@@ -1084,7 +1082,7 @@ describe('GrpcService', function() {
         it('should end stream with a thrown error', function(done) {
           var error = new Error('Error.');
 
-          fakeUtil.decorateRequest = function() {
+          grpcService.decorateRequest_ = function() {
             throw error;
           };
 
@@ -1340,9 +1338,8 @@ describe('GrpcService', function() {
         it('should decorate the request', function(done) {
           var decoratedRequest = {};
 
-          fakeUtil.decorateRequest = function(reqOpts, config) {
+          grpcService.decorateRequest_ = function(reqOpts) {
             assert.strictEqual(reqOpts, REQ_OPTS);
-            assert.deepEqual(config, { projectId: grpcService.projectId });
             return decoratedRequest;
           };
 
@@ -1360,7 +1357,7 @@ describe('GrpcService', function() {
         var error = new Error('Error.');
 
         it('should end stream with a thrown error', function(done) {
-          fakeUtil.decorateRequest = function() {
+          grpcService.decorateRequest_ = function() {
             throw error;
           };
 
@@ -1660,6 +1657,41 @@ describe('GrpcService', function() {
     });
   });
 
+  describe('decorateRequest_', function() {
+    it('should delete custom API values without modifying object', function() {
+      var reqOpts = {
+        autoPaginate: true,
+        autoPaginateVal: true,
+        objectMode: true
+      };
+
+      var originalReqOpts = extend({}, reqOpts);
+
+      assert.deepEqual(grpcService.decorateRequest_(reqOpts), {});
+      assert.deepEqual(reqOpts, originalReqOpts);
+    });
+
+    it('should execute and return replaceProjectIdToken', function() {
+      var reqOpts = {
+        a: 'b',
+        c: 'd'
+      };
+
+      var replacedReqOpts = {};
+
+      fakeUtil.replaceProjectIdToken = function(reqOpts_, projectId) {
+        assert.deepEqual(reqOpts_, reqOpts);
+        assert.strictEqual(projectId, grpcService.projectId);
+        return replacedReqOpts;
+      };
+
+      assert.strictEqual(
+        grpcService.decorateRequest_(reqOpts),
+        replacedReqOpts
+      );
+    });
+  });
+
   describe('getGrpcCredentials_', function() {
     it('should get credentials from the auth client', function(done) {
       grpcService.authClient = {
@@ -1698,6 +1730,7 @@ describe('GrpcService', function() {
       beforeEach(function() {
         grpcService.authClient = {
           getAuthClient: function(callback) {
+            grpcService.authClient = AUTH_CLIENT;
             callback(null, AUTH_CLIENT);
           }
         };
diff --git a/packages/common/src/util.js b/packages/common/src/util.js
index 00f52b3a821..d4592cb0319 100644
--- a/packages/common/src/util.js
+++ b/packages/common/src/util.js
@@ -487,14 +487,18 @@ function decorateRequest(reqOpts, config) {
   if (is.object(reqOpts.qs)) {
     delete reqOpts.qs.autoPaginate;
     delete reqOpts.qs.autoPaginateVal;
+    reqOpts.qs = util.replaceProjectIdToken(reqOpts.qs, config.projectId);
   }
 
   if (is.object(reqOpts.json)) {
     delete reqOpts.json.autoPaginate;
     delete reqOpts.json.autoPaginateVal;
+    reqOpts.json = util.replaceProjectIdToken(reqOpts.json, config.projectId);
   }
 
-  return util.replaceProjectIdToken(reqOpts, config.projectId);
+  reqOpts.uri = util.replaceProjectIdToken(reqOpts.uri, config.projectId);
+
+  return reqOpts;
 }
 
 util.decorateRequest = decorateRequest;
diff --git a/packages/common/test/util.js b/packages/common/test/util.js
index 92e11d6f67c..ad807ca2819 100644
--- a/packages/common/test/util.js
+++ b/packages/common/test/util.js
@@ -1276,22 +1276,66 @@ describe('common/util', function() {
       assert.strictEqual(decoratedReqOpts.json.autoPaginateVal, undefined);
     });
 
+    it('should replace project ID tokens for qs object', function() {
+      var config = {
+        projectId: 'project-id'
+      };
+      var reqOpts = {
+        uri: 'http://',
+        qs: {}
+      };
+      var decoratedQs = {};
+
+      utilOverrides.replaceProjectIdToken = function(qs, projectId) {
+        utilOverrides = {};
+        assert.strictEqual(qs, reqOpts.qs);
+        assert.strictEqual(projectId, config.projectId);
+        return decoratedQs;
+      };
+
+      var decoratedRequest = util.decorateRequest(reqOpts, config);
+      assert.strictEqual(decoratedRequest.qs, decoratedQs);
+    });
+
+    it('should replace project ID tokens for json object', function() {
+      var config = {
+        projectId: 'project-id'
+      };
+      var reqOpts = {
+        uri: 'http://',
+        json: {}
+      };
+      var decoratedJson = {};
+
+      utilOverrides.replaceProjectIdToken = function(json, projectId) {
+        utilOverrides = {};
+        assert.strictEqual(reqOpts.json, json);
+        assert.strictEqual(projectId, config.projectId);
+        return decoratedJson;
+      };
+
+      var decoratedRequest = util.decorateRequest(reqOpts, config);
+      assert.strictEqual(decoratedRequest.json, decoratedJson);
+    });
+
     it('should decorate the request', function() {
       var config = {
         projectId: 'project-id'
       };
-      var reqOpts = {};
-      var decoratedReqOpts = {};
+      var reqOpts = {
+        uri: 'http://'
+      };
+      var decoratedUri = 'http://decorated';
 
-      utilOverrides.replaceProjectIdToken = function(reqOpts_, projectId) {
-        assert.strictEqual(reqOpts_, reqOpts);
+      utilOverrides.replaceProjectIdToken = function(uri, projectId) {
+        assert.strictEqual(uri, reqOpts.uri);
         assert.strictEqual(projectId, config.projectId);
-        return decoratedReqOpts;
+        return decoratedUri;
       };
 
-      assert.strictEqual(
+      assert.deepEqual(
         util.decorateRequest(reqOpts, config),
-        decoratedReqOpts
+        { uri: decoratedUri }
       );
     });
   });
diff --git a/packages/compute/package.json b/packages/compute/package.json
index 7aea04822c7..5e66ab70bdb 100644
--- a/packages/compute/package.json
+++ b/packages/compute/package.json
@@ -63,7 +63,8 @@
     "concat-stream": "^1.5.0",
     "mocha": "^3.0.1",
     "propprop": "^0.3.0",
-    "proxyquire": "^1.7.10"
+    "proxyquire": "^1.7.10",
+    "uuid": "^3.0.1"
   },
   "scripts": {
     "publish-module": "node ../../scripts/publish.js compute",
diff --git a/packages/compute/src/vm.js b/packages/compute/src/vm.js
index 84b5a361f4d..4907fd4e912 100644
--- a/packages/compute/src/vm.js
+++ b/packages/compute/src/vm.js
@@ -342,6 +342,11 @@ VM.prototype.detachDisk = function(disk, callback) {
       return;
     }
 
+    var diskName = common.util.replaceProjectIdToken(
+      disk.formattedName,
+      self.zone.compute.authClient.projectId
+    );
+
     var deviceName;
     var baseUrl = 'https://www.googleapis.com/compute/v1/';
     var disks = metadata.disks || [];
@@ -352,7 +357,7 @@ VM.prototype.detachDisk = function(disk, callback) {
       var attachedDisk = disks[i];
       var source = attachedDisk.source.replace(baseUrl, '');
 
-      if (source === disk.formattedName) {
+      if (source === diskName) {
         deviceName = attachedDisk.deviceName;
       }
     }
diff --git a/packages/compute/test/vm.js b/packages/compute/test/vm.js
index 380381e01b1..99e06aa6b53 100644
--- a/packages/compute/test/vm.js
+++ b/packages/compute/test/vm.js
@@ -23,6 +23,8 @@ var proxyquire = require('proxyquire');
 var ServiceObject = require('@google-cloud/common').ServiceObject;
 var util = require('@google-cloud/common').util;
 
+var utilCached = extend({}, util);
+
 var promisified = false;
 var fakeUtil = extend({}, util, {
   promisifyAll: function(Class) {
@@ -46,7 +48,12 @@ describe('VM', function() {
   var Disk;
   var DISK;
 
-  var COMPUTE = { projectId: 'project-id' };
+  var COMPUTE = {
+    authClient: {
+      projectId: 'project-id'
+    },
+    projectId: 'project-id'
+  };
   var ZONE = {
     compute: COMPUTE,
     name: 'us-central1-a',
@@ -70,6 +77,7 @@ describe('VM', function() {
   });
 
   beforeEach(function() {
+    extend(fakeUtil, utilCached);
     vm = new VM(ZONE, VM_NAME);
     DISK = new Disk(ZONE, 'disk-name');
   });
@@ -229,7 +237,7 @@ describe('VM', function() {
     beforeEach(function() {
       DEVICE_NAME = DISK.formattedName;
 
-      METADATA = METADATA = {
+      METADATA = {
         disks: [
           {
             source: DEVICE_NAME,
@@ -254,6 +262,36 @@ describe('VM', function() {
       });
     });
 
+    it('should replace projectId token in disk name', function(done) {
+      var REPLACED_DEVICE_NAME = 'replaced-device-name';
+
+      fakeUtil.replaceProjectIdToken = function(value, projectId) {
+        assert.strictEqual(value, DISK.formattedName);
+        assert.strictEqual(projectId, COMPUTE.authClient.projectId);
+        return REPLACED_DEVICE_NAME;
+      };
+
+      vm.getMetadata = function(callback) {
+        var metadata = {
+          disks: [
+            {
+              source: REPLACED_DEVICE_NAME,
+              deviceName: REPLACED_DEVICE_NAME
+            }
+          ]
+        };
+
+        callback(null, metadata, metadata);
+      };
+
+      vm.request = function(reqOpts) {
+        assert.strictEqual(reqOpts.qs.deviceName, REPLACED_DEVICE_NAME);
+        done();
+      };
+
+      vm.detachDisk(DISK, assert.ifError);
+    });
+
     it('should return an error if device name not found', function(done) {
       var metadata = {
         disks: [