Dorman 674-540 Exhaust Manifold - Front

Dorman 674-540 Exhaust Manifold

This Dorman exhaust manifold is engineered to match the fit and function of the original front manifold on specified vehicles. Built from cast iron with a natural finish, it includes the gaskets and downpipe hardware needed for a complete exhaust repair on applications such as Buick LeSabre, Pontiac Bonneville, and Chevrolet Impala.

Key Features

• Cast iron construction for durable exhaust service
• Natural finish
• Round port shape
• Includes gasket and mounting hardware
• Direct replacement for the front exhaust manifold on listed vehicles
• Part number: 674-540

Detailed Description

Dorman 674-540 is a replacement exhaust manifold designed for front-position applications across a wide range of GM sedans and coupes. It is built to match the original manifold’s fit and function, helping restore proper exhaust routing on vehicles including the Buick LeSabre, Buick Park Avenue, Pontiac Bonneville, and Chevrolet Impala. The cast iron body supports long-term exhaust service, while the included gasket and downpipe hardware help complete the repair with the correct service parts.

This part cross-references ATP 101273 for the same application.

What It Helps Fix

• Exhaust leaks at the manifold flange
• Cracked or warped original manifold housing
• Broken or missing manifold mounting points
• Noise from a leaking front exhaust manifold
• Failed sealing surfaces at the cylinder head or downpipe connection

Installation Notes and Tips

Install on the front exhaust manifold position only for the listed applications. Verify port shape, gasket alignment, and mounting points before tightening fasteners. Inspect the mating surfaces, studs, and nuts during service to help ensure a proper seal. This part includes the manifold gasket and downpipe hardware listed in the package contents.

Quality Assurance

Dorman manufactures this manifold to match original fit and function on specified vehicles. Part number 674-540 is built as a regular-grade replacement for front-position exhaust manifold service on compatible Buick, Pontiac, Chevrolet, and Oldsmobile applications.