Delco Remy is a benchmark brand in heavy-duty starting and charging systems, supplying OEM and aftermarket starters and alternators for Class 8 trucks including Peterbilt models. Their 39MT and 41MT starters and 21SI and 28SI alternators are industry-standard components found on trucks powered by Cummins, PACCAR, and other commercial diesel engines. When a starter or alternator fails on the road, Delco Remy replacements offer dependable performance and broad compatibility across Peterbilt model years.