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G503 WWII Willys Ford Jeep Deep Mud Exhaust

The G503 WWII Willys Ford Jeep Deep Mud Exhaust was a modification that was made to allow the military vehicle to drive into 18 inches of water without the engine dying

This article applies to Willys MB WWII Military Jeeps 

1. According to Nabholtz the Deep Mud system was added to the jeep in the Late contracts W-6 and F-5 in Dec 44 for MB's. AAW book shows that there was an Ord reference in 7/44. We have seen MB's in 10/44 with Deep Mud Exhaust. In the Ord 9 SNL 1949 version, you have very little to see how the exhaust was configured. Here you see the key areas that will clamp the exhaust running under the rear seat.

2. Some vendors have the Deep Mud exhaust kit (i.e. Brent Mullin) The kit will come with clamps and the exhaust pipe and muffler. This will extend all the way to the back of the jeep.

3. There are a couple of hard to find parts that you may need to manufacture yourself. If your frame is set up for Deep Mud, you should have a hole drilled in the frame for this hook.

4. Fabricating this piece is pretty easy, it appears to be about 2.5 inches long and 1 1/4 inch length in the bottom hook section. This will hook the muffler clamp as shown.

5. After fabricating muffler hook, Connect to the frame with a 5/16x24 - 1" with lock washer.

6. At the back of the muffler there should be a frame extention that is specific to hold the back end of the muffler clamp as shown here. 5/16x24 - 1" bolt with nut and lock washer

7. Stepping back to take a look at the path of the exhaust pipe. Here you see an article from Army Motors showing the path of the deep mud exhaust.

8. Next is the connection to the Crossmember which holds the machine gun mount plate. This clamp will connect to a rubber insulator, and the other side of the insulator to the crossmember as shown in the picture.

9. Its worth noting here, with this picture of an original Willys midsection clamp. You will note that the clamp bolted directly to the frame (and the clamp is much more sturdy than the kit). The isulator allows for vibration where as this picture shows a sturdy connection to the frame.

10. The next section connects to the crossmember that hold your transmission. This connection is a little tricky as the clamp is used as a hook around another clamp as shown. In some cases, this bracket on the crossmember can be missing if it was modified to send the exhaust out the side by the passenger.

11. The next piece is the clamp to the flex hose. This is a simple connection and tightening of the clamp as shown.

12. The last piece is the flex pipe to the exhaust manifold. This is an easy connection as well with the flex pipe. You can bend it into position and then tighten and your done!

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