SOHC really THAT bad?

[Jason94sport]

I hear from this forum it is...But I hear from others not on the internet different.
My uncle had an 03 for 10 years, Never had any problems. The Ford guy I know also said they get some in but it's not like they are flooded with SOHC engine problem customers.

I can't believe that the number of 02-05 ones out there on the road are blowing timeing chains left & right. There are thousands of them. When one passes by me I don't hear anything abnormal. They are all over the place where I live.

I'm looking an 02 to replace my 1st gen.

 

[Tech By Trade]

Yes, mine is a 2nd gen sport trac, same as the fourth gen explorder. Supposedly has the upgrades to the timing chain guides. I just spent 2 months dancing around replacing the timing chains myself. Not a fun or cheap job. I cant believe how much plastic they crammed into this motor.

 

[Varsity]

I happen to have the OHV in my truck thankfully, but after looking at some newer Sports and Sport Tracs, I found myself wondering the same thing.

My understanding was that the trucks affected most were trucks that see wild temperature changes. Plastic only works for so long, so if your motor is seeing 80 degree days and then -20 degree days, the temperature changes can take its toll on plastic. Also, not following proper oil change intervals lead to poor/inadequate lubrication on start-up leaving the chains to thrash around for awhile.

I don't own a SOHC, but that's my understanding of what usually causes them to crap out. However, there's always some owners who seem to beat the odds or contradict these so I don't really know. I've also seen people on here who meticulously change their oil and live in a predominantly warm climate have issues and vice versa. As far as I can tell, I haven't really heard any definite causes. I'm sure a little luck never hurts either...haha Subscribed so i can hear various people's experiences.

 

[chefduane]

I haven't had any issues with mine... so far. So far being 193k miles. But I do regular maintenance and scheduled oil changes are a must. Mobil-1 with a good filter.
Anything that breaks or has issues I immediately address it and repair it or install a new part. I have had my share of expensive repairs, trans rebuild being one. But I've done brakes w/ new rotors & calipers, radiator, steering rack, upper & lower balls and control arms, shocks, U&L intake mani gaskets, among other things. And I do regular fluid changes on the transfer and diff. The timing chain cassettes have never been addressed but no problems so far, and no death rattle. Thing runs like a champ and I'll drive it till she gives up the ghost. There is a thread here about hi-mileage SOHC's and there are many around. That said, there are some that just crap out at 75k miles. I think in my situation longevity has been a combo of good maintenance and yes, probably some luck.

 

[Jason94sport]

Would lack of use increase the chance of problems? This is not going to be a DD or driven more then 1 or 2 days a week.

 

[chefduane]

I would think that lack of use, while easy on wear parts, typically allows seals & gaskets to get dry, shrivel, and crack. That would mean various fluid leaks when you fire it up. Also, gas can go bad, dry out and varnish interior components. There are folks here that know much better than I that can speak more accurately about that.

 

[Toucan]

I have a SOHC in my '98. Been in garage for two weeks (parts hard to come by for that year). Knocked out plastic guides at 106637 miles. This makes the first time I take any vehicle I have owned (all Fords) to a mechanic since the mid '80's. I have this for 11 years and it has served me well. In reading I note that after 85,000 many of these engines do pop the "plastics".

By the way I should be getting mine back late this evening. I took the opportunity to change all gaskets and do a complete engine clean up. Including changing water pump. Parts $375.00 Labour $200.00.

 

[boominXplorer]

Its all in the quality in oil used. I have seen them broken to pieces just over 100k but they are usually in under maintained engines. I have also done one with 210k that was still running with noise and it was the back one gone. It was a very clean engine and the maintenance showed. All the front tensioners were still in tact and it was a 98 engine. The rear tensioner is a horrible design and usually will fail by 150k mi. Replace them all and your good for another 150k.

 

[2TimingTom]

Driving it once or twice a week won't let anything adverse happen to it. It's those motors that sit for months that develop problems.

 

[Anime]

It's not "bad", it's just that the SOHC 4.0L is a more complex engine, with all the stuff that makes it a SOHC design stacked on the 4.0L block instead of the simpler OHV design.

More complex means more stuff to break.

The timing and cam drive components just aren't that great. They are long chains with lots of friction points. You are just going to have a greater chance of issues when you have 3 long chains on an engine instead of 1 short chain.

Also as mentioned, the design that Ford used wasn't that great, either. Ford really just threw a SOHC setup on the 4.0L block to update the motor since it was cheaper than designing a new engine from scratch, and apparently they didn't have anything else to use instead. Like the OHV, the SOHC evolved through the model years and so the later models with it probably have a better motor in some ways than the first models that came with it.

The SOHC is a great motor in a lot of ways, at least for driving and on paper, but it's just more complex to work on, parts are more expensive, and you just need to be prepared for that stuff if you're going to go from a OHV 4.0L to a SOHC 4.0L.

If the timing/drive chain work has already been done on a motor or you have the time and money to pull the engine and replace those parts when you get a vehicle that has the SOHC, you can just replace the trouble parts BEFORE issues happen and save yourself a lot of hassle down the road.

You should read the SOHC timing chain replacement how-to theads and maybe some of the others to see what you may be getting into. If it looks like too much work or something you probably won't do yourself and might not be able to pay to have done, you can figure that you might want to keep what you have now.

If you can get an 02 that has timing/drive chain issues for cheap and fix it up, that may be a good way to go, if the issues haven't caused damage yet. Buying an 02 with plenty of miles that doesn't have any noise yet but which has never had a chain replacement is going to mean you'll be doing it as some point if you are driving it when it gets to 100-150K.

I can see the draw of a newer Explorer, but the first gen is hard to beat for working on, but even the various 4.0L OHVs in Explorers over the years have still shown to be dependable engines.

 

[Toucan]

Having owned cars that had engines that "caved in" at 60,000 miles I can only say the the SOHC is a good engine. Granted I have not owned an OHV.
In speaking to a friend last night he opined/said that engines used between 2002 and 2012 are the "worst" ever, to use his word. All I can say is that in proper maintenance is given this things should last you for quite a while.
My speciality was lubrication - my years in the petroleum industry afforded me that. Will find out later as I had already planned to obtain a replacement in June this year.

 

[Jason94sport]

I can see the draw of a newer Explorer, but the first gen is hard to beat for working on, but even the various 4.0L OHVs in Explorers over the years have still shown to be dependable engines.

And they have been for me, the problem is everything around the engine...the body is rusting out on the roof on mine. Nothing I have found is any better. Runs great, but 22 years catches up....
I think I'm going to try it...Maintenance I have no way of knowing but the 2 I am looking at are 85K & 94K miles & they seem to drive fine & no noises. I see complete engines are plentiful, I can always go that route.

 

[Anime]

Mine developed the rust on the roof around the water channels, especially at the windshield, but it's easy enough to fix with a welder and some sheet metal. PITA to remove the headliner to do it but it's cake compared to fixing the rocker panels and underbody rust.

With 85K & 94K I would guess they will require the timing/cam chain fix eventually. If you plan for it and maybe buy the parts cheap ahead of time and can budget the time to pull the engine and get the work done, maybe it'll be worth it in the end. If you can't do it yourself and have to pay, you are probably going to spend as much on the labor as you paid for the vehicle.

I'd be tempted by newer Explorers if they had 2 doors, but they don't.

 

[Jason94sport]

Sports with the 5 speed are what I am looking at...

 

[Toucan]

I have seen deals at Copart. That is where I bought mine. It had a bent bumper, no chassis damage, and needed some body work around gas tank cover. Cost to get that done was $300.00. I paid Copart $3700.00. It had less than 55,000 miles - in 2004.

The only problem with us here in Belize is that These vehicles from insurance companies are in many cases fairly new vehicles and the customs authorities apply the "Blue Book" valuation method and have a field day with you. Many times you end up paying import duties in excess of 4 times what you paid for the vehicle. However, in some instances even that is worth the while.
Duty rates around 45% of 4cyl, 55% on 6cyl and 78% on 8 cyl on "their" valuation.

 

[Jason94sport]

Ok well thanks guys.,...I decided to not buy a 3rd gen with this engine. One I was looking at sold & the other I just couldn't bring myself to trust it.....
So I'm spending a little $ on my 1st gen & going to keep it.

 

[chefduane]

That's a reasonable decision. At least you know exactly what you have, what needs fixing, and what has already been fixed. Best of luck!

 

[Anime]

Probably a good idea...


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