Replacing tensioners without replacing cassettes and chains?

[MusicLover]

I bought a 2004 SportTrac 4.0L SOHC 4x4 two years ago which now has 346,000 km on it (about 207,600 miles). The timing chain tensioners have never been replaced and I have seen many different articles suggesting that these tensioners be replaced every 75,000 miles.

Although there is no noise at cold startup, I am certain that the tensioners are quite unable to do their job properly because they must be very worn out simply because of the high mileage.

I am wondering....is it okay to replace just the tensioners on such a high mileage engine without replacing the cassettes and chains?

My concern is that 1)the new tensioners will put too much tension on the rest of the system, the old plastic cassettes may have become very brittle if that is possible and fail in a catastrophic way after the new tensioners are put in and 2)the tighter tension from new tensioners will tend to quickly stretch the old and worn out chains to the point where they become loose and start to make noise or worse yet, fail in a catastrophic way

Oil has always been just regular 5W30...there is not one drop of oil that leaks and as far as I know after owning the truck for about two years it does not burn any oil. It runs great and there are no unusual ticking or rattling noises from the engine. I live in a brutally cold winter climate (minus 35) and quite hot in the summer (95 F) and the conventional 5W30 works well.

So the other question is...if there is no noise, do the tensioners even need to be replaced?

I am looking forward to hearing any feedback on this issue and it would be greatly appreciated.

Thanks in advance.
Mark

 

[koda2000]

IMO, with that many miles, changing the tensioners (especially with no current noises) is just asking for trouble and will likely do more harm than good. Just keep doing what you're doing maintenance wise.

 

[sr139fox]

I would leave it alone. Keep up the maintenance and drive it like you stole it.
Dave P.

 

[swshawaii]

Anyone know if the anti drain back valve has any effect when the filter is mounted vertically as with the 4.0L SOHC?
Regardless, for less than $5 almost anywhere, the Motorcraft FL820-S is hard to beat. JMO
Motorcraft FL-820S Oil Filter Cutaway Comparison | Ford Explorer and Ford Ranger Forums - Serious Explorations

Here's the perfect wrench for it with matching flute pattern. Use a 1" SIX point socket, NOT the 3/8" square drive. Another JMO.
https://www.amazon.com/Hopkins-10606-FloTool-Graphite-Filter/dp/B000EH0OQE

 

[koda2000]

I've always used Motorcraft oil filters (good enough for Ford, good enough for me). However I use Mobil 1 Extended Performance oil, because I can get 12 months/15,000 miles out of an oil change and with as many vehicles as I maintain it makes my life easier. The problem is that I figure the Motorcraft oil filters are only good for a max of 7,500 miles, so I change the filters 1/2 way through the oil change interval. This is kinda a PITA. So this time around I'm thinking about trying the new Purolator filter that's supposed to be good for 15,000 miles (typically most of my vehicles don't travel more than 10,000 miles per year) or the Mobil 1 EP filter. Of course they are both more than twice the price of the Motorcraft oil filter, so no cost savings there, other than the quart of oil I loose 1/2 way the interval.

IDK if the anti-drainback valve helps, considering the way the filter mounts vertically on the SOHC engine. I know it does on some Toyota engines though.

 

[Paul Fithian]

If it is not making noise on cold start up, leave it alone.

If you do decide to change them, use Italian made Ford parts, not Asian made Cloyes or other. See Post #50 in this thread:

http://www.explorerforum.com/xenfor...c-v6-timing-chain-parts-sources.317039/page-2

 

[koda2000]

Seriously... If it ain't broke don't fix it. New tensioners on ancient cassettes can cause them to break. Then you'll be kicking yourself for having messed with it.

 

[ptf18]

I had to replace the engine in our 02 because of failed tensioneers . With 73k on the replacement engine (Ford replacement engine) I am getting ready to replace both tensioners at 75k. I dont hear/notice any timing chain "noises" but think I'll change out the tensioners....just because....

Am I looking at this issue correctly?
The advise to the OP seems to be different than my line of thinking.