When it comes to oil change intervals, Rod Halsten, a master technician at Barkley GMC, in Tuscaloosa, Alabama, says his personal preference is doing oil/filter changes dictated by the pickup’s use.
GM has specific guidelines in the owner’s manual. But Halsten says fleet users should take advantage of engine oil analysis, like Mobil and others offer, to determine the best intervals.
If oil analysis isn’t used, Halsten recommends oil/filter changes be done every 3,500-4,000 milesI for Duramax engines used in typical field-service work, or when towing is a regular task.
As for the best oil, he suggests using a premium oil such as Mobil Delvac Super 1300 10W-40.
“The biggest common problem I see related to oil/filter changes is over-tightening the oil filter,” says Halsten.
“You can do more damage by over-tightening the filter than stretching the oil-change interval; it only needs to be tightened 1 to 1-1/4 turns after gasket contact.”
Here’s another tip: Always fill the new filter with engine oil before putting it on so the critical areas of the engine have oil immediately.
“Don’t worry about oil spilling out when you tip the filter sideways to put on – there’s a check valve that prevents that from happening,” assures the seasoned GM tech.
