Had the "Suspension Failure" error come up about a month ago. Read up and tried the following to eliminate it.
1. Installed a Bag Pipin Andy seal in the air compressor. May have helped, issue was intermittent and was a couple of day before it came back.
2. Cleaned battery terminals and the ground points in the truck. This did nothing.
3. Finally located the front ground posts. This was easy, cleaned and buttoned back up.
Cleaning the three front ground posts seems to have fixed this issue. Also it feels like the eCat system is working better. Ride seems better than before.
The posts in the trunk were clean. The front ground posts had white oxidation all over. This will be an annual service. Took all of 10 minutes to complete.