4.0 SOHC - when did it become reliable? | Ford Explorer Forums - Serious Explorations

  • Register Today It's free!

4.0 SOHC - when did it become reliable?

adowns

New Member
Joined
June 20, 2011
Messages
6
Reaction score
0
City, State
Alabaster, AL
Year, Model & Trim Level
1998 Mountaineer
Did the 4.0 SOHC engine ever become a reliable 200k mile engine?

After what year is it safe to purchase an Explorer with this engine?

If the timing chain problems have been fixed under warranty, does it become a reliable 200k engine, or is it good for only another 50k?

Do rebuilt engines (like a Jasper engine) fix the timing chain issues or are they about the same as the original engine as far as reliabilty?

I would like to buy a late 90's early 2000's Explorer. They seem like a lot of SUV for the money, but I am leery of the 4.0 SOHC engine which seems to be the engine in most of them.
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





It has always has issues of some sorts. 97-02 are the most problematic.
 






my opinions

I believe all of the timing chain related improvements were incorporated in the 2002 and later models. An engine rebuilt or repaired after 2002 could have the best components available. There are less expensive and inferior aftermarket timing chain replacement kits available.

A forum member with a late model recently experienced a balance shaft tensioner failure at around 45K miles. Many members have over 200,000 miles on their engines with no timing chain issues. Maintenance and driving habits affect the longevity of the timing chain components. My 2000 engine was poorly maintained by previous owners and the original rear timing chain guide broke at 150,000 miles. I added a pre-oiler to hopefully extend the life of my timing chain components.

Volvo requires replacement of the timing belt and tensioner every 70,000 miles. Most modern overhead cam engines require a similar replacement interval. Ford's mistake was making it necessary to remove the engine to replace the rear cassette.

If you're not a home mechanic look for a 5.0L V8/4R70W powertrain.
 






I agree on the 5.0,mine had 182,000 when I sold it and it ran like crazy.Always started and ran very smooth,never a problem with the tranny either.:D
 






Thanks all for the information. Now I see the situation. If routine timing chain maintenance were not so difficult this wouldn't be an issue. I will look for a post 2002 owned by one of those "change oil every 3000 miles" owners.
 






You might want to look for atleast a 2003 or newer. The 2002 are know to be more problematic since that was the first year of the 3rd gen explorer.
 






03 or 04 engines have the updated black guilds in them.
 






being an employee of jasper engines i can tell you this, the guides are different from stock. i dont really know if its because of the issue being discussed i could find out tho. if you would like for me to
 






To 01sporty: I've often wondered if engine rebuilders use better than stock parts because they can see first hand what the weak spots are as they tear down the core engines. Or... do they use cheaper parts because the second engine will probably outlast the car which already has lots of miles and the car will break down due to some other cause or be sold to another owner.
 






we use high quality parts, we partner with alot of the aftermarket parts companies in order to get better pricing, kinda one hand washes the other they sell more parts we get better prices, our engines are rebuilt to factory specs. so they are as good as new. i cant speak for other facilities but i imagine they wouldnt remain competetive if they sold an inferior product. in fact we remanufacture engines for the long life postal vehicles and those engines have to stand up to the torture that the postal service puts them thru, and trust me when i say this those engines are absolutely put thru the ringer
 






Well I do know that my first X (2000 EB 4.0) had head gasket issues, I checked into repairing it. Local shops wanted atleast 3k, ford wanted 3800 just to repair, and a new motor was 4k.

I got it because he price was right ($500).... I later traded it off after finding out the repair cost.

I'm in agreement if I was to have a later model X, I'd get the 5.0 motor.
 






Did the 4.0 SOHC engine ever become a reliable 200k mile engine?

After what year is it safe to purchase an Explorer with this engine?

If the timing chain problems have been fixed under warranty, does it become a reliable 200k engine, or is it good for only another 50k?

Do rebuilt engines (like a Jasper engine) fix the timing chain issues or are they about the same as the original engine as far as reliabilty?

I would like to buy a late 90's early 2000's Explorer. They seem like a lot of SUV for the money, but I am leery of the 4.0 SOHC engine which seems to be the engine in most of them.
I have a 4.0 sohc with 200,000 and have only had to just keep up the maintenance I'm very pleased with it
 






2006 Eddie B 4.0L with 202k. Sixth owner, no death rattle.

Don't have maintenance records for it, but I know it was a fleet/rental vehicle. It must've been maintained, because it runs pretty good...aside from rotted suspension bits.
 












My 2002 (built 4/02) SOHC V6 has 128K and runs great. The motor is strong and idles very smooth.

Previous owner handed me a 1” thick folder of maintenance receipts, and I’m continuing that maintenance. I see no reason I shouldn’t get 70-80K more if I take care of the motor.

Mobil 1 and a Wix XP every 4K.
 






'04 V-6 SOHC, 165k, no work ever done on chains yet. Minor failures, yes, wheel bearings, TCC solenoid quit. Beyond that, no problems. Happy, but still worried. imp
 






I have a 2006 SOHC 4.0 Ranger 4x4 5 speed outside with 320K miles on the stock engine, runs fine. Owner changes oil every 3-5000K miles and uses synthetic with Motorcraft filter.
He has never done any maintenance other then that and a fuel pump.
The later model 4.0 are very good, clean oil changes with full synthetic are the KEY
 






Also use a Motorcraft oil filter only. And keep an eye on oil pressure.

These engines are just super sensitive to the quality of the oil and unfortunately Ford did not make synthetic a requirement on these engines (ultimately it is up to the owner to maintain the vehicle, but making people aware of the reasons might have gone a long way to keeping these motors functional)

When properly maintained these engines can last and they have a decent powerband to top it off. (make more HP than the V8 and a little less torque)
 






I think the sohc gets a bad rap because you have to pull the engine to replace back chain look at overhead cam chain driven and it has to be changed periodically
roscoe
 



Join the Elite Explorers for $20 each year.
Elite Explorer members see no advertisements, no banner ads, no double underlined links,.
Add an avatar, upload photo attachments, and more!
.





I think the sohc gets a bad rap because you have to pull the engine to replace back chain look at overhead cam chain driven and it has to be changed periodically
roscoe

That's a valid statement. However, Ford's 4.0L SOHC implementation of the camshaft chain tensioners is less reliable than many others. Below is a photo of my 4.6L DOHC V8.
OilPan.jpg

The cassette structural support is composed of metal. Only the chain wear surface is "plastic". On the SOHC V6 the cassette structural support is "plastic" that fails due to thermal and vibration fatigue.
RCasset.jpg
 






Back
Top