Distributor gear wear

[Diamond2J]

First post here. I tried looking around for the answer and found a few helpful things, but am hoping for some other ideas.

I have a 1997 K2500 Cheyenne with 204k miles on a 5.7 Vortec. I noticed it started to run rough, and checked out the timing. 29 degrees . I pulled out the distributor and it's got some pretty good wear on the bottom gear. The gear teeth aren't square anymore, rather they are sharp like a blade edge. See the pictures I linked (click for higher resolution)

What would cause this? Is my oil pump failing and asking that gear work real hard? I haven't ever had low oil pressure. It rotated easily, not spinning, but can be easily turned.
I'm also pretty sure it's the OEM part. I recently adjusted the timing in our 96 K1500 Sierra with 215K miles on it (replaced intake manifold gaskets) and the gears still looked really nice and clean.

I'm really curious about what would cause this kind of wear? I assume it got out of time because of the worn gear teeth. I was considering "upgrading" to a cast aluminum distributor (A-Team) but I'm wondering if I have bigger issues and should take care of that now instead...Any input is appreciated.

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ETA - Sorry about the low resolution, not sure what the deal is there

 

[evilunclegrimace]

It is a common problem with vortec engines. Order a new gear and install it on the distributor.

 

[movietvet]

Welcome to the forum from Oregon.

What @evilunclegrimace said. Once you replace the gear, you will be back in good shape.

 

[Schurkey]

I noticed it started to run rough, and checked out the timing. 29 degrees ...

...I assume it got out of time because of the worn gear teeth.

That's not ignition timing. That's the synchronization error between the crank sensor signal, and the cam sensor signal.

Turning the distributor does not change the ignition timing, unless you turn it so far that the spark jumps to the wrong terminal on the distributor cap.

As said--worn distributor gear is a common problem on Vortec engines. Be sure the bushings holding the distributor mainshaft are in usable condition--that's another common Vortec distributor problem.

 

[Diamond2J]

Welcome to the forum from Oregon.

What @evilunclegrimace said. Once you replace the gear, you will be back in good shape.

It is a common problem with vortec engines. Order a new gear and install it on the distributor.

Thank you both! I had an extra laying around. I put a camera down to the cam area and those gears looked fine. Since it's so common in the vortecs, what what causes this kind of wear? I have two other 5.7 vortecs with higher mileage that still have the original in it with nowhere near the wear, and the extra I had laying around is the same story so I'm curious to understand it better.

...That's not ignition timing. That's the synchronization error between the crank sensor signal, and the cam sensor signal...

I appreciate you pointing that out. I'm still learning. I noticed the wires on the cam position sensor are pretty threadbare, one only had one left. I ordered the new connector because I thought it might give me trouble. If I'm understanding your post correctly, maybe it already was?

 

[Caman96]

This one:
GM Genuine Parts 10457356 Ignition Distributor Drive Gear

https://www.amazon.com/gp/aw/d/B000C9BXDC/ref=ox_sc_saved_image_10?smid=ATVPDKIKX0DER&psc=1

 

[evilunclegrimace]

This one:
GM Genuine Parts 10457356 Ignition Distributor Drive Gear

https://www.amazon.com/gp/aw/d/B000C9BXDC/ref=ox_sc_saved_image_10?smid=ATVPDKIKX0DER&psc=1

That is a very good price!

 

[Caman96]

That is a very good price!

Then you’ll love this!

https://www.amazon.com/gp/aw/d/B000C9BXDC/ref=ox_sc_act_image_1?smid=AEXEHA1YU5633&psc=1

 

[rebelyell]

Recently saw a post this site (& I verified info) showing display ads from Both NAPA Echlin and SMP (Standard Motor Products) ... BOTH offering brand new USA-made Vortec V6 & V8 complete distributors for $100 - $120 depending where ya buy. USA, 3 yr/36 mo warranty. Contrast that with a $40 + melonized gear or a good but $pricey$ Vortec cap+rotor. One of the ads even specified the distributors are made in its Greenville SC (USA) plant. Sorry, But No, I don't recall the PNs. Neither of them appeared to have aluminum housings; all seem to be black composite (as are OE).

** found some

The NAPA Echlin distributor PN's are DA100 and DA101 (NOT DSA ,repeat NOT DSA)

 

[Caman96]

Recently saw a post this site (& I verified info) showing display ads from Both NAPA Echlin and SMP (Standard Motor Products) ... BOTH offering brand new USA-made Vortec V6 & V8 complete distributors for $100 - $120 depending where ya buy. USA, 3 yr/36 mo warranty. Contrast that with a $40 + melonized gear or a good but $pricey$ Vortec cap+rotor. One of the ads even specified the distributors are made in its Greenville SC (USA) plant. Sorry, But No, I don't recall the PNs. Neither of them appeared to have aluminum housings; all seem to be black composite (as are OE).

** found some

The NAPA Echlin distributor PN's are DA100 and DA101 (NOT DSA ,repeat NOT DSA)

That possibly could’ve been me. I’ve moved to this camp:

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