Ford 300 I-6 Cam gear material choice

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Noticed while changing the oil on my old truck yesterday that the slow oil leak around the front timing cover has turned into a pretty significant one. I'd heard of the "Fiber" cam gear on these engines being a weak spot, and I'm sure mine has the original one in place. Seems like replacing it would be the thing to do preventatively while I have the timing cover off (Looks like a rad out grill out job to get access with pullers and everything). Question is should I replace it with another fiber gear, a cast iron gear or an aluminum gear? I'm leaning towards a metal gear, although I'm concerned about the additional noise. Also hard to call the OEM fiber gear a failure since its survived 34yrs. Anyone have any experience with these?
 
Noticed while changing the oil on my old truck yesterday that the slow oil leak around the front timing cover has turned into a pretty significant one. I'd heard of the "Fiber" cam gear on these engines being a weak spot, and I'm sure mine has the original one in place. Seems like replacing it would be the thing to do preventatively while I have the timing cover off (Looks like a rad out grill out job to get access with pullers and everything). Question is should I replace it with another fiber gear, a cast iron gear or an aluminum gear? I'm leaning towards a metal gear, although I'm concerned about the additional noise. Also hard to call the OEM fiber gear a failure since its survived 34yrs. Anyone have any experience with these?
Mine disintegrated while I was towing a car down the 401 due to it getting a bit hot (E-brake was sticking, wasn't aware) which resulted in an expensive tow. I swapped it out for a 302HO, lol.

You are right that a metal gear will probably whine, though I'd be concerned about the quality of aftermarket replacement nylon gears.
 
The fiber gears were common to fail in the old Chevy 235 and 216 engines in the passenger cars. Most replace with aluminum when rebuilding engine, as the truck engines used the aluminum gear from new.

Overkill makes excellent point about the possible quality of the new replacement nylon gear.
 
Can you even get the fiber gear? I did one and used the aluminum gear. Couldn't really hear any difference in the engine compartment while stationary, no way anyone could hear it while driving.
 
Melling makes all 3 options. I also have some reservations about an aftermarket fiber gear. Any reason to use the Aluminum over the Iron? I assume its quieter. I'll probably just end up ordering the iron gear...

 
They used the nylon teeth on engines with timing chains to stop noise too . I replaced dozens with steel gears and never heard anything different.

I doubt you will hear anything even though it's gear to gear. I'm guessing that the aluminum one would wear in quick and not make any noise at all.
 
Would aluminum last as long as the original "fiber"?
A friend has a 1992(?) F-150 with that engine. It whines conspicuously, as heard from outside with the engine idling. Is that timing-gear noise?
We had a 1966 F-100 with the 240in³ (shorter stroke, same bore) version of that engine. It didn't whine that way.
 
Do you guys know that when the last LS engine blows up a 300 will haul it to the scrap yard?

I used to buy vans and pickups with 300 sixes all day long. I've put over 300,000 miles on a few of them without ever going into the engines.
I've rebuilt a few and always used iron gears.
 
Had the fibre gears replaces with steel years ago on my 88 E250 club wagon with the 300ci engine. The noise wasn't significantly different other than a bit of "singing" at idle, but even that was absolutely minor. go with steel and never have a problem.
 
This is an easy choice: iron. Assuming the OEM crank gear is iron, there's absolutely no reason to choose either a softer metal nor plastic as a substitute.

As far as noise: these are helical cut gears. Sure, the OEM Nylon cam gear may have provided an inconsequential level of noise reduction in exchange for drastically reduced service life. A cast gear will be more than acceptable.
 
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