25 Ram 3500 emissions

akhdram · Jan 19, 2026

mbarber84 said:
Lots to take in here:

Some initial points:

You’ll need a pretty high level scan tool and a bypass to get able to perform a parked regeneration. Since it’s a 2025, you may be forced to go through the dealership as it’s an all new CAN-FD architecture that a lot of aftermarket devices can’t fully communicate with.

Has your truck ever been back to the dealer since its initial purchase? There have been a multitude of software updates for these trucks that were focused on fixing a variety of issues to include DEF / SCR problems.

Don’t know for sure if it’ll work on 2025+ trucks, but on 2024 and older model years, if you got into a bind where you had an SCR / DEF related failure resulting in a 150 mile countdown to 5mph speed limited mode, you can continue to drive normally even when the counter reaches 0 miles remaining. So long as you don’t shut it down and restart, stop and sit in idle / park for long, or attempt to put fuel in the tank after the 0 miles remaining, it’ll still let you drive normally. As a work-around, you can disconnect all four wheel speed sensors, you could drive it continuously until you reached your destination with no problems aside from some more codes.

I checked for any tsbs and only one for safety about restraint system going offline. No emissions . Is software updates different? I bought it in sep at a dealership in Idaho then drove back to AK. Di my own oil changes since the dealership is always booked and here in AK they charge $500 at least that was the going price in 2018 when I took my 17 Ram 2500. Might be double today.

HarryN · Jan 20, 2026

There are some companies that make diesel based heaters for situations like this.

Here is an example unit.

The idea is that in addition to what you have done, form a sort of air enclosure under your truck and blow the warm air into the pocket under your truck.

Hopefully it helps to thaw out whatever is frozen or stuck.

There are other companies that make these as well - this one is just rated for really cold temperature use.