Dodge V8 Exhaust Manifold Replacement

By The Boss

I had to replace the driver side exhasut manifold due to it being cracked. I could not afford headers so I was givena set of old manifolds from a friend that had swapped to headers and needed to get rid his old manifolds. Lucky for me...

To start, be sure the engine is completely cool. Then with a wire brush, scrape as much rust and mud buildup from the bolt heads, nuts and studs as possile. Then spray liberally with Liquid Wrench, PB BLaster or some other quality penetrating lube. WD-40 ain't going to cut it if there is any rust at all on the manifolds. Do not forget to spray the manifold-to-exhaust clamp bolts from the bottom to get the nuts. You may also need a set of gaskets if the heads or manifolds are not perfectly flat. I bought some Victor Reinz gasket from Napa for $12, but ended up not using them.

Remove spark plug wires from the plugs. Loosen all of the hardware from the manifolds (1/2" socket) and then remove the manifold-to-exhasut bolts (9/16" socket and wrench). Remove the manifold hardware completely. There are 2 bolts/washers on each side the front and rear cylinders and 2 nuts/washers on studs on the outside of center cylinders. The manifolds will easily hang from the center studs. Clean and inspect the hardware. If damaged, replace.

Remove the manifolds. Here you can see the crack that is the problem, it goes around three sides.

To minimize any stress on the rest of the exhaust system, you may wish to support the y-pipe with a jack stand or other support.

Manifolds removed. Notice the lack of gasket material. Dodge does not use gaskets on their exahust manifolds.

Y-pipes and center studs that need to be inspected and cleaned.

Quick shot of the exhasut port with my rusty exhaust valve stem. No heavy carbon build up or oily residue. Good sign...

Of course it started to rain when reassembling.

Here is the newly sand blasted and painted (high temp paint) replacement manifold. Ain't it pretty? Won't last long on my truck.... You will need to double check the moutning surface for any warpage using a long straight edge.

Installation is reverse of removal. The hardest side is the driver side due to the brake booster and steering components. Slide the manifold onto the center studs, fit the output onto the y-pipe and then thread in the bolts. It will take some time to get the bolts to line up correctly with the holes. You may need to wiggle the mainfold around. Torque the manifold hardware to 25 lb-ft in three stages, from the center out on each stage. Bolt the y-pipe to the mainfold. You will need the 9/16" deep socket and possibly the box wrench.The bolts had some "keepers" to help minimize the need to hold the head with a wrench, but mine were broken. On my truck, I needed nearly 20" of extensions to reach the underside of the y-pipe clamp.

Connect the plug wires and you are all set. Start motor, check for leaks.