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Recipe - Cummins 6.7L ISB Diesel (Ram HD, 2019+ generation)

Specific Fix build

Reliability tier: aggregated - verify before ordering, see /disclosure/

DEF system repair for 2019+ Ram HD (mode DEF quality / freezing inducements (2019+ 6.7)): contaminated/crystallized DEF, failed urea pump modules and doser faults. The verified OEM urea pump/level module is 68458603AB (supersedes 68353830AC). crystallization from stale or contaminated fluid is the root cause pattern - fix the fluid and the module together, not the module alone.

Parts

• 6.7L Cummins DEF Pump Module, 2019+ (OEM Mopar) - OEM urea pump/level module 68458603AB - the verified replacement (qty 1)
• DEF refill - fresh API-certified fluid (service item, any 2019+ Ram 6.7L) - fresh, sealed ISO 22241 DEF - never reuse suspect fluid; flush the tank if it crystallized (qty 1)
• 6.7L Cummins DEF (Urea) Pump/Level Module (Mopar 68457124AE) - harness/heater elements checked while in there - cold-climate freeze faults mimic pump death (qty 1)

Install order

1. read codes and separate: doser/pressure faults vs level/quality sensor faults vs freeze-related harness faults
2. drain and inspect the tank: crystals or contamination -> flush before any module goes in
3. replace the urea pump/level module; prime per procedure
4. fill with fresh sealed DEF; verify dosing pressure and clear the fault pattern with a drive cycle

Expected outcome

DEF dosing pressure in spec, no quality/level faults, no repeat crystallization.

Do not

• do not install a new module into a contaminated tank - it dies the same death
• do not top off with old/opened DEF jugs - ISO 22241 freshness is the whole game

Parts budget

About $290-$340 in parts, plus parts we have no price for. It depends on what the diagnosis finds; each option below is what you buy together. Prices marked "at Dave's" are Dave's Auto Center's, the same as in his store; the others are approximate prices from OEM and maker catalogs, rounded (a manufacturer's list price can run higher). Parts only, no labor.

• about $290 plus parts we have no price for: 6.7L Cummins DEF Pump Module, 2019+ (OEM Mopar) (about $290) + def fluid (no price yet)
• about $340: def pump heater (about $340)

DIY or shop: Either: module swap is reachable for a confident DIY; the priming/verification step makes it a shop job for some.