Spare ECM?

[Steve Hayes]

In general, I'm wondering if it is worthwhile to buy a spare ECM to program and keep the stock ECM stock?

[bai78]

If you're still under a warranty & need to take it in for any repair/TSB work, than yes. It also never hurts to have another one handy that works & has already done the CASE relearn. In a pinch, you could always swap them out to get your truck running.

I have a spare upgraded module along with the original that came with the truck.