diff --git a/src/lhisp-oauth-client.t.ts b/src/lhisp-oauth-client.t.ts
index a4bf572..0fdaf45 100644
--- a/src/lhisp-oauth-client.t.ts
+++ b/src/lhisp-oauth-client.t.ts
@@ -18,6 +18,7 @@ export interface LhispOauthClientConstructorParams {
   authHeaders?: Headers;
   grantType?: string;
   authContentType?: ContentType;
+  authData: Record<string, string>;
   sendAuthCredentialsOnRequestBody?: boolean;
   formatAccessToken?: (accessToken?: AccessToken) => string;
   debug?: boolean;
diff --git a/src/lhisp-oauth-client.ts b/src/lhisp-oauth-client.ts
index c26024a..2d45b7b 100644
--- a/src/lhisp-oauth-client.ts
+++ b/src/lhisp-oauth-client.ts
@@ -28,6 +28,7 @@ export class LhispOauthClient<iAccessToken extends AccessToken = AccessToken> {
   protected authHeaders?: AxiosHeaders;
   protected grantType?: string;
   protected agent: https.Agent;
+  protected authData: Record<string, string> = {};
   protected accessToken?: iAccessToken;
   protected refreshToken?: iAccessToken;
   protected tokenCreatedAt = 0;
@@ -51,6 +52,7 @@ export class LhispOauthClient<iAccessToken extends AccessToken = AccessToken> {
     this.certificado = params.certificado;
     this.headers = (params.headers ? params.headers : {}) as any as AxiosHeaders;
     this.authHeaders = (params.authHeaders ? params.authHeaders : {}) as any as AxiosHeaders;
+    this.authData = params.authData;
     this.apiUrl = params.apiUrl;
     this.authUrl = params.authUrl;
     this.authScope = params.authScope;
@@ -105,7 +107,9 @@ export class LhispOauthClient<iAccessToken extends AccessToken = AccessToken> {
           "Content-Type": this.authContentType,
           ...this.authHeaders,
         },
-        data: {},
+        data: {
+          ...this.authData,
+        },
       };
 
       if (this.grantType) authRequestOpt.data.grant_type = this.grantType;