04 Duramax starting problem
 

i recently purchased a 2004 2500 HD GMC duramax with 160,000 miles. about every 10th time i try to start it the starter spins but does not engage the flywheel. i had the starter replaced but it still does it. does anybody have any thoughts or suggestions.

Any alarms or kill switches installed?? You might have a low voltage problem on the solinoid side of the starter

no alarms or kill switches. the new starter was installed last week but the problem persisted after i got the new starter.

sounds like it may be a bad spot on the flywheel possibly i would remove the starter and turn the crank and inspect the teeth on the flywheel....and also remove starter and make sure that the bendix is coming out all the way and if they're ok then it may need shimming possibly

I have the same problem at 85,000 miles. replaced the starter and it is worse. It's like the starter is spinning too soon and hitting the the flywheel. The old starter showed good engagement wear pattern on the teeth. I have not seen a post anywhere that has found a solution and some are two years old. Maybe they found the solution and stopped posting?

I put a new starter in it and it works much better. I had to remove the exhaust pipe to get the starter out. I expect I will put in multiple starters unit I get one that does not spin the starter too soon. Trial and error seems the only choice now. Seems nothing is wrong with the flywheel, it is all caused by the starter. I am selling the truck tomorrow, so I hope it works for him!

New parts are not always good parts, esspecially if you are dealing with rebuilt stuff.