Erki
Well-Known Member
Ever since I bought my 2006 duramax its gone through starters every year or two. I think im on my 3rd. And my buddy has an 07 classic same engine/trans and never had a problem. I bought the truck from his uncle. And his son had bought the truck brand new. From whative heard is its been this way its whole life and after some research its not just this truck. Some got the problem and some did not. Read some solved it by changing the flexplate and starter and for some trucks that did not make a difference. Possibly something to do with a casting problem from different factories.
So what happens is the starter will work great for quite a while. Then about once a month when you go to start it the starter will just grind against the flexplate instead of engaging. Over time it will happen more often and then will start to grind 2 or 3 times before engaging. Then its starter replacement time. Which is also a small painful process on the LBZ. (Wheel off, inner liner out, exhaust clamp unbolted etc...)
I talked to a friend about the problem and he suggested grinding the tapered part of the teeth on the starter a little deeper and more angle to allow easier meshing and help to align and engage the flywheel. It was hard for me to do this test on a brand new $300 starter. But after my latest starter installed had a bad solenoid one month later I took it out and exchanged for a new one on warrantee. I happened to have one of my old ones still that had started grinding regularly and had gotten changed out but the teeth on the starter still looked good. Unlike the one when i bought the truck that was missing about 4 or 5 teeth on the starter.
I took my old starter and did a grinding modification test. Increased the taper angle with sharper front endge on the teeth. I put the old starter back in that was removed because it was grinding all the time on startup. It has not ground against the flexplate since. It does crank quite a bit slower than the new one and maybe that helps. I still have a brand new one in the box that I will attempt to modify and install this summer so it cranks faster. I will try to get pictures of the process at that time. I dont know if this will be a permanent fix but its definitely made a huge difference so far. I may even get the one i have already modified rebuilt so it spins faster too.
Sorry for the long post. I know ive done a lot of searching on this subject and never found a definite solution. I also dont feel like pulling the transmission and changing the flexplate to "hope" that fixes it.
So what happens is the starter will work great for quite a while. Then about once a month when you go to start it the starter will just grind against the flexplate instead of engaging. Over time it will happen more often and then will start to grind 2 or 3 times before engaging. Then its starter replacement time. Which is also a small painful process on the LBZ. (Wheel off, inner liner out, exhaust clamp unbolted etc...)
I talked to a friend about the problem and he suggested grinding the tapered part of the teeth on the starter a little deeper and more angle to allow easier meshing and help to align and engage the flywheel. It was hard for me to do this test on a brand new $300 starter. But after my latest starter installed had a bad solenoid one month later I took it out and exchanged for a new one on warrantee. I happened to have one of my old ones still that had started grinding regularly and had gotten changed out but the teeth on the starter still looked good. Unlike the one when i bought the truck that was missing about 4 or 5 teeth on the starter.
I took my old starter and did a grinding modification test. Increased the taper angle with sharper front endge on the teeth. I put the old starter back in that was removed because it was grinding all the time on startup. It has not ground against the flexplate since. It does crank quite a bit slower than the new one and maybe that helps. I still have a brand new one in the box that I will attempt to modify and install this summer so it cranks faster. I will try to get pictures of the process at that time. I dont know if this will be a permanent fix but its definitely made a huge difference so far. I may even get the one i have already modified rebuilt so it spins faster too.
Sorry for the long post. I know ive done a lot of searching on this subject and never found a definite solution. I also dont feel like pulling the transmission and changing the flexplate to "hope" that fixes it.
