app.module.ts

////
providers:[
{provide: XHRBackend, useClass: DefaultXHRBackend},



//

default-xhr-backend.ts

import {Injectable} from '@angular/core';
import {
    BrowserXhr,
    Request, Response,
    ResponseOptions,
    XHRBackend,
    XHRConnection,
    XSRFStrategy
} from '@angular/http';
import 'rxjs/add/operator/map';

@Injectable()
export class DefaultXHRBackend extends XHRBackend {


    constructor(browserXHR: BrowserXhr,
                baseResponseOptions: ResponseOptions,
                xsrfStrategy: XSRFStrategy) {
        super(browserXHR, baseResponseOptions, xsrfStrategy);
    }


    createConnection(request: Request): XHRConnection {
        let xhrConnection = super.createConnection(request);
        xhrConnection.response = xhrConnection
            .response
            .map((response) => {
                this.tokenSetter(response);
                return response;
            });

        return xhrConnection;
    }

    tokenSetter(response: Response) {
        if (response.headers.has('Authorization')) {
            let authorization = response.headers.get('Authorization');
            let token = authorization.replace('Bearer ', '');
            //armazenar token renovado no local storage
            //use aqui o window.localstorage para atualizar o token
            //para não precisar de injeção de dependência do serviço de armazenamento
        }
    }
}