I inherited a 1998 C1500, 6-cylinder automatic with 111k miles a few months ago. The engine struggled to turn over on start-up, so I replaced the starter with a new one in early July. That seemed to fix the issue and the new starter cranked like a champ.

A week ago on Tuesday, we got a flooding storm and I drove through some standing water a couple of times. I parked the truck and drove it one more time that night with no problem. On Wednesday morning I tried to start it and it cranked initially but didn't fire right off. The second time I turned the key it just made the following noise:


I tried again twice that day and the next day but got the same result. Since we had gotten all the rain, I thought maybe that had caused something, so I decided to let it set for a couple of days in the sun and make sure everything dried out completely. I went out Sunday and it cranked and fired up normally, so I figured all was good. I drove it to work Monday, which meant that it started three times with no problem.

This morning, the problem was back, so I shot the video at the link above. The weather was dry yesterday and last night, but it was a cool morning, so there was a heavy dew on the hood.

I don't know if this is really moisture related or if the new starter is bad.

 

Sure sounds like a bad starter in the video. I just went through that recently with my 1996 C1500.

If you drove through standing water, the starter likely got water inside it - it's on the bottom of the engine after all, and the starter and/or starter solenoid are corroding and going bad. The noise in your video is typical for a starter solenoid issue. In the morning maybe condensation inside the housing due to cooler overnight temperatures caused it to not start today.

Hopefully if you got the starter locally, its under warranty. Somewhere like Autozone will swap it no questions asked if it's under their warranty. Once you replace it, I would avoid driving through standing water that is deep enough to be up to the starter (a foot maybe?).

 

It sounds like the starter gear is slipping against the flex plate teeth.

Did you happen to notice if a shim was present on the old starter? It would’ve been between the starter and block. If present, did you transfer it to the new starter?

A couple of things to try:

1) Rotate the crankshaft at least 1/4 turn (clockwise only as viewed from the front) with a socket & ratchet and attempt to start. If it starts no problem, there’s likely a section of stripped/damaged teeth on the flex plate. Remove the starter or inspection cover (if equipped) and rotate the engine manually to inspect the flex plate.

2) Remove the starter and inspect the drive gear shaft for excessive play side-to-side/top-to-bottom. Play can be present at the nose cone, armature or both. If present, the starter will need replacement (which you can probably get under warranty if you play your cards right) and it will need to be shimmed because the drive gear-to-flex plate clearance is too small.