Originally Posted by Alleyman
Want to replace the plugs on our 8.1 Workhorse ,(2004) and not sure what might be best. What type and brand is everyone using for best performance?
2004 Dolphin 5355.
Alleyman, You want to use AC/Delco Platinum tipped plugs part number: 41-983 or the current updated plug; gapped to .060.
You can also use the AC/Delco 41-932 was the replacement plug gapped at .045.
The AC/Delco 41-932 was replaced with the 42-993. Same plug just a different number.
Accept no substitutes. You can always enter the Workhorse Forum for discussion about spark plugs. It's a very popular topic. Use the Search function enter "workhorse spark plugs".