Maintenance and Fluid Information for 2003 GMC C6500 Topkick 200/210/230/250/275/300 HP Isuzu 6HK1
If you are planning an oil change on a 2003 GMC C6500 Topkick 200/210/230/250/275/300 HP Isuzu 6HK1, the product lookup gives you two useful starting points: the engine-oil grades listed are 15W-40 and 5W-40. The matching product listings include Heavy-Duty Synthetic Diesel Oil 15W-40, Heavy-Duty Synthetic Diesel Oil 5W-40, Signature Series Max-Duty Synthetic Diesel Oil 15W-40. Before buying oil, confirm that the product also meets the applicable manufacturer specification.
What oil and oil filter are listed for my 2003 GMC C6500 Topkick 200/210/230/250/275/300 HP Isuzu 6HK1?
The listed engine-oil viscosity is 15W-40, 5W-40, and listed oil-filter part numbers include P559128-EA.
Does severe driving affect oil-change timing for my 2003 GMC C6500 Topkick 200/210/230/250/275/300 HP Isuzu 6HK1?
Use the manufacturer’s maintenance schedule for this engine and operating conditions. The available application data does not establish an exact oil-change interval.

