diff --git a/lib/index.ts b/lib/index.ts
index b3350abc92..dcbbd230e0 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -43,7 +43,7 @@ type ParentNspNameMatchFn = (
 interface EngineOptions {
   /**
    * how many ms without a pong packet to consider the connection closed
-   * @default 5000
+   * @default 20000
    */
   pingTimeout: number;
   /**
@@ -93,10 +93,12 @@ interface EngineOptions {
   httpCompression: boolean | object;
   /**
    * what WebSocket server implementation to use. Specified module must
-   * conform to the ws interface (see ws module api docs). Default value is ws.
-   * An alternative c++ addon is also available by installing uws module.
+   * conform to the ws interface (see ws module api docs).
+   * An alternative c++ addon is also available by installing eiows module.
+   *
+   * @default `require("ws").Server`
    */
-  wsEngine: string;
+  wsEngine: Function;
   /**
    * an optional packet which will be concatenated to the handshake packet emitted by Engine.IO.
    */
diff --git a/package-lock.json b/package-lock.json
index 4140bcf9db..ac0583e45a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1206,9 +1206,9 @@
       }
     },
     "engine.io": {
-      "version": "4.1.0",
-      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-4.1.0.tgz",
-      "integrity": "sha512-vW7EAtn0HDQ4MtT5QbmCHF17TaYLONv2/JwdYsq9USPRZVM4zG7WB3k0Nc321z8EuSOlhGokrYlYx4176QhD0A==",
+      "version": "5.0.0",
+      "resolved": "https://registry.npmjs.org/engine.io/-/engine.io-5.0.0.tgz",
+      "integrity": "sha512-BATIdDV3H1SrE9/u2BAotvsmjJg0t1P4+vGedImSs1lkFAtQdvk4Ev1y4LDiPF7BPWgXWEG+NDY+nLvW3UrMWw==",
       "requires": {
         "accepts": "~1.3.4",
         "base64id": "2.0.0",
diff --git a/package.json b/package.json
index a350cd78b0..30e97e7b77 100644
--- a/package.json
+++ b/package.json
@@ -51,7 +51,7 @@
     "accepts": "~1.3.4",
     "base64id": "~2.0.0",
     "debug": "~4.3.1",
-    "engine.io": "~4.1.0",
+    "engine.io": "~5.0.0",
     "socket.io-adapter": "~2.2.0",
     "socket.io-parser": "~4.0.3"
   },
diff --git a/test/socket.io.ts b/test/socket.io.ts
index 0733feee81..9678496b77 100644
--- a/test/socket.io.ts
+++ b/test/socket.io.ts
@@ -228,7 +228,7 @@ describe("socket.io", () => {
       });
       request
         .options("http://localhost:54013/socket.io/default/")
-        .query({ transport: "polling" })
+        .query({ transport: "polling", EIO: 4 })
         .set("Origin", "http://localhost:54023")
         .end((err, res) => {
           expect(res.status).to.be(204);
@@ -256,7 +256,7 @@ describe("socket.io", () => {
       });
       request
         .get("http://localhost:54014/socket.io/default/")
-        .query({ transport: "polling" })
+        .query({ transport: "polling", EIO: 4 })
         .set("Origin", "http://localhost:54024")
         .end((err, res) => {
           expect(res.status).to.be(200);
@@ -276,7 +276,7 @@ describe("socket.io", () => {
 
       request
         .get("http://localhost:54022/socket.io/default/")
-        .query({ transport: "polling" })
+        .query({ transport: "polling", EIO: 4 })
         .end((err, res) => {
           expect(res.status).to.be(200);
           done();
@@ -290,7 +290,7 @@ describe("socket.io", () => {
       request
         .get("http://localhost:54023/socket.io/default/")
         .set("origin", "http://foo.example")
-        .query({ transport: "polling" })
+        .query({ transport: "polling", EIO: 4 })
         .end((err, res) => {
           expect(res.status).to.be(403);
           done();