I have a 95 4x4 f150 with the good ol' 4.9 inline 6. This truck has ~193k miles on it, and I was wondering if I should be worried about the cam/crank gears on this engine? I have done some digging and it seems like they commonly go out at about 200K miles (where I am sitting now). When it goes out, does it bend pushrods/valves, or is it just a "quiet death"? Am I running on borrowed time, or would it be okay to leave it alone until the engine needs to come out for an overhaul?

 

It's non-interference, so "quiet" death. The gears do wear but the motor should still run up to 300k, although the timing will be off leading up to that.

 

If well taken care of, these things have been known to go over 500,000 miles.

1981 Ford F150 4x2 - 1981 F-150 Explorer Custom

 

Thanks guys, that is what I needed to know.

My engine is very well taken care of, now. The previous owner neglected it terribly, however.

 

I can't remember - didn't Ford switch back to all metal gears sometime before '95?
Is there any reliable info on when Ford used the fiber cam gear? I keep hearing different stories.

 

I don't know the answer to that. I am going to have to do some research now and find out, thanks for sharing that question with me.

 

If you're concerned about them, you can remove your timing cover and have a look.

Rent a harmonic balancer puller.

Drain and remove the radiator.
Remove the fan.
Pull the balancer.
Remove the timing cover.

The gears will be right out in the open. You can inspect them for wear, nicks, damage, etc.

From what I've heard, when fiber gears go out, they just GO. Like, a nick on a tooth finally becomes too much, the tooth comes off, and then it snowballs quickly and the gear shreds the teeth off. There won't be any slow symptoms such as timing being off (doesn't happen with gear-to-gear anyway).

 

I have access to all the tools I would need, and all the help I would need. Now I am curious about if Ford ever switched over to metal gears.. I would hate to tear my truck apart just to find out it already has metal gears and is nothing to worry about..

 

I inspected mine earlier this summer. I think the job took me around 2 - 3 hours total.

About the only thing that must be replaced for the job is the timing cover gasket. About $17.


From what I've read, they used the fiber gears all the way to the end. However, parts stores list metal and fiber for a '95, so it's possible that maybe metal gears were used in some applications. Possibly F250/F350 300s? Not sure.

Either way, it's very possible your '95 has fiber gears, and I don't think you'd know unless you looked.


But, of course, looking is totally your call and would be for peace of mind more than anything else.

 

I think I am going to just leave it alone and hope it doesn't shear any teeth off. I have been dreaming about swapping in a 4bt in it's place anyways, so if it does go out, that will just give me a reason to do the swap.

 

That's about the only engine I'd change out my 300 for.

 

Agreed. These old 300's are just plain cool. Couldn't ask for a better engine in a 1/2 ton pickup, that's for sure.

 

I would be more suspicious of a torque converter and/or automatic transmission, or a pilot or throwout bearing, than the gears at the front.

JMO.

 

I'm not chasing down a noise here, I was just curious if I should be worried about the timing gears with that many miles on them.

 

If it works, don't fix it.