I tried to do this as well, but once the VIN is assigned, the build is locked in. I realized need to add a front license plate holder to mine, but the dealer said it’s too late. Fortunately that’s a minor inconvenience and minimal cost for me to fix.
The only other option that I can think of is to walk away from the deal and start again. But prices will be higher, so it might be a wash.
If I was in your shoes, I’d take it with the 3.73 and see how it goes, and then start shopping for a 4.10 upgrade if you really need it.
I’ve spoken to several “long term” Hemi HD guys who swore by the 4.10 when they had their old 6 speed trucks, but are reporting that the 8 speed makes a world of difference.
If you’re getting a CTD, you might be stuck in 5th gear if your load is really heavy…..
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