IDM moisture shield

[mchan68]

Is anyone aware of any aftermarket moisture shield that exists? I've had two customers recently complaining of having to replace TWO IDMs due to the dreaded moisture intrusion problem. The latest one, the owner try to rig up his own piece of cardboard over top. Kind of reminds me of the days people used to wrap bags over distributor caps.

[Alex Bruene]

All that I am aware of is the 3 foam pieces you should be able to get from your parts department. I have never seen one fail a second time with those installed in the correct locations.

[Keith Browning]

Michael, To prevent repeat water intrusion issues you need to prevent water getting to the module vent on the back side. A cover might work but you will waste a lot of time fabricating something that might stay or look professional. Thats not a knock on your abilities. Here is a simple solution I started using years ago when this problem became evident:

• Remove the module and the bracket as an assembly so that you can work on a bench.

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• Remove the old module from the bracket and clean the bracket off.

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• Position the module on the bracket as it is installed on the truck to be sure it oriented as it will be on the truck.

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• Apply a bead of silicone in in the shape of an upside down "u" AROUND THE VENT but not so close that the silicone will spread and cover/seal the vent when bolted together.

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• Bolt the module to the bracket and install in the truck

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[mchan68]

Yes, Alex, I've done that TSB a couple of times with the three rubber pieces. I just have a hard time imagining how it eliminates a repeat water intrusion concern. Thanks Keith, I'll keep that in mind.