Diesel

A revised Cummins turbo-diesel six-cylinder engine makes the refreshed 2025 Ram 2500 one of the slickest-driving heavy-duty trucks on the market.

For 2025, a new 6.7-liter Cummins turbo-diesel six-cylinder makes a little more horsepower than its predecessor in the Ram 2500 and 3500 Heavy Duty trucks.

For the 2025 model year, Chevy has kept updates to just some new colors and changes in standard equipment across the Silverado 1500 lineup.

Another major GM recall affecting diesel-equipped pickup trucks and SUVs involves a transmission control valve that may fail.

Diesel engines don’t have spark plugs; instead, they use the super-heated air created by their high compression ratios to ignite the diesel fuel as it’s injected into the cylinder.

Die-hard fans may lament the passing of the Hemi V-8, but the 2025 Ram 1500’s new Hurricane twin-turbo straight-six engines make up in power and smoothness what they lack in audible growl.

Cold weather adversely affects diesel engines more than gas engines, but that’s only partly due to the engine itself.

Ram will recall more than 600,000 heavy-duty pickup trucks to reprogram their emissions-control systems after it was discovered that the trucks contain software that allowed them to emit more than the acceptable level of nitrogen oxide.

Chevrolet has given both SUVs a mid-cycle refresh for 2025 to add new tech and help make them feel smaller.

Chevy has given the Tahoe and Suburban a mild update with some freshened styling, a bump in power for one of the three available engines and a revised interior.