Preventative replacement of quiet camshaft sync or leave well enough alone?

[lobo411]

1996 Explorer 4.0 OHV, 172k.

I thought I had a bad camshaft synchronizer due to squeaks/squeals, but it turned out to be a bad Dorman harmonic balancer. My lower intake manifold gasket has been leaking oil from the valley area, and I kind of want to replace the gasket. FYI--the old style one-piece gasket never leaked a drop in 10 years, and you can still get it by order. If I decide to replace the lower gasket, should I also replace the camshaft synchronizer as preventative maintenance just because it's easily accessible with the intake manifolds removed?

The camshaft synchro is quiet--no squeaks or squeals, and I lubed it with oil to keep it that way. I do have some kind of WOOO noise from the passenger rear upper engine area that is only audible by stethoscope, but I haven't been able to isolate it to the sync.

I'm of two minds on this:
#1--Leave well enough alone. I already got burned by replacing a good OEM part with a crap Chinese part (the Dorman harmonic balancer) just as "preventative maintenance." Yes, it would be easier to replace it with the lower intake removed, but I'm better off replacing the camshaft synchro with the lower intake installed if it starts doing the classic mouse squeak at some later date.

#2--Replace it. It has 172k on it, it's a $35 part, it could be the source of the WOOO noise, and it would be way easier to do with the upper and lower manifolds removed. I ordered a Cardone reman synchro on the theory that I would at least get a Motorcraft housing that way.

Votes? What would you do? Replace now when it's easiest to do so, or wait until you know for sure it's the problem (but then you have to work around the lower manifold)?

 

[koda2000]

If it ain't broke, don't fix it.

 

[96eb96]

The synchronizer generally has a squeak when it fails. Also you need an alignment tool and you have to verify you are at 1-TDC when you install that - it is like installing a distributor. I wouldn't fix that preventatively - it is not something that will strand you on an OHV. I just replaced a rusty freeze plug on that same engine - it was a tiny leak and when i touched it with a screwdriver it it turned into a steady pee. I am not going to replace all of them.

 

[Rhett]

I say leave it alone. On the 4.0 OHV it's a pain to replace even with the mani's removed.

If it starts squeeking you can still run the truck, and replace it at your leisure.

 

[lobo411]

Thanks for the advice, guys! I'm gonna leave it alone, then. I've been putting about 3000 miles a year on the truck, so at that rate it could basically last forever.