Everyones Opinion on the 4.0L

[Tee Rev]

i work at a ford dealer on these 4.0 all the time the only way i would own one would be under warranty. they have too many problems the engine is poorly designed.

That's a pretty vague reason. How about a list of items? What problems? Why do you believe that they are poorly designed.


As a multiple 4.0L owner(OHV & SOHC) since 1991, I've never had any issues.
I've even got a 1991 OHV 4.0L Ranger that runs low 14's N/A @ 5000' above sea level with what I consider to be minor mods.

 

[rickcdewitt]

a 302 won't get good mileage at slow speeds though.

 

[jeffro184]

That's a pretty vague reason. How about a list of items? What problems? Why do you believe that they are poorly designed.

problems:
OHV Engine.
-cracked heads
-intake gaskets split fill oil with coolant takes out bottom end
-rocker arms and push rods wear into each other and rattle bad
-rear of intake gaskets leak oil
OHC Engine
-timing chain issues (all 3) cassettes brake, primary gets sloppy, tentioners go bad,
-vacuum leaks at intake all years, and at egr tube.
-heater shut offs go bad overheat happens engine usually junk.
-vibration dampers break engine vibrates bad takes out main bearings
-just a few examples.
-pain in but to work on.

poor design when went to ohc engine. when it was a ohv engine it was based off 2.9l engine. when went to ohc it was a completely redesigned engine, instead of going to the modular engine (4.6, 5.4, 6.8) design, they design the pos we are stuck with today. could have had a 6.8 v10, take off 2 cyls have a 5.4 take off 2 more have a 4.0 all intechangeable parts (pistons, rods, front cover, basic engine design but they went a different more expensive route, the modular engines by then were developed and good. they had to recast the block to accodate timing chains front and rear with a jack shaft and some a balance shaft, the modulars have 2 chains both up front much better design and easier to work on. plus now with the 4.0 to time it properly you have to spend $500 in special tools for all the holders and aligners and it is quite a project if you dont do it all the timme and it is too easy for something to slip. modulars mark the chain the way in the book telss and line up the marks no special tools need. i think it was a poor shot at a redesign engine
just my 2 cent

 

[Ranger44]

OHV Engine.
-cracked heads
-intake gaskets split fill oil with coolant takes out bottom end
-rocker arms and push rods wear into each other and rattle bad
-rear of intake gaskets leak oil

All these things can be improved upon and if properly maintained can be avoided.

Cacked heads~Can be replaced with aftermarket castings from alabama cylinder heads or king cylinder heads. They have thicker decks and is just a better casting all around.

Rocker arms and pushrods- Delta Cam's rocker arm and pushrod set have hardened inserts and treated pushrods.

There are issues with the intake gasket, but if oil and coolant are both properly monitered as it's supposed to be, then engine failure is slim to none.

Although I defended the OHV, I do agree with you on the OHC version. It would have made a great deal of sense to use the modular design for a OHC 4.0 as the modualrs are great engines.

 

[jeffro184]

key word is properly maintained most people just drive and dont check anything these days brings in work though

 

[Stranger ranger]

i'll lay a brick on the pedal, walk away and come back tomorrow and all it will be is out of gas.

 

[Ranger44]

key word is properly maintained most people just drive and dont check anything these days brings in work though

I'd have to agree.

 

[Kona]

Just remember if you change the spark plugs on a modular at the wrong temperature you WILL spit a spark plug out! 5.0 is a good engine but apparently it is a huge amount of hours to stuff in a Ranger and set up ( Jeffro184 can maybe clarify that for us) the 4.0 OHV is a drop in and will work well if maintained the SOHC as said is weak but not any harder to install.

 

[Sevensecondsuv]

I agree the OHC has some issues that make it undesirable.

The OHV's intake manifold gasket issues are all due to the retarded outside to inside bolt torqing sequence that is published everywhere, and I assumed they used from the factory. Take it off, clean the surface, put a new fel-pro gasket on it, and torque it from the inside out and you will have zero problems.

The heads and head gaskets are only a problem on vehicles that had a neglected cooling system.

The rockers and pushrods do wear out over time but there are aftermarket replacements that are better. Even the stock ones are good for 200,000 miles. They're so easy to replace I don't think it's a bad deal at all every 200,000.

I'd take the bottom end of a 4.0 over the bottom end of a 5.0 any day. I tore my 4.0 apart when it had 163,000 on it, 1000 miles with a dead spark plug wire (gas washing the cylinder), and 30,000 burning coolant in the same cylinder (cracked head). That cylinder looked the same as the others, with the factory cross hatch nicely visible. I simply cleaned the piston, did a little ridge reaming and put it back together with new heads (which are rediculously cheap compared to other engines). It's running great to this day.

 

[jeffro184]

oh come on now the 5.0 is easy to put in j/k. if you have time and patience its ok. expecially if the front end is of the truck and you can slide it all in. using a kit to put it in was easy. i also have a body lift. if no body lift figure saying bye bye to the air box for heat or a/c

 

[slimchriz]

I think the 4.0 is great I got mine at 100k and I know almost none of the maintenance was kept up on...(was father in-laws) when I got it.
When I got it I flushed the coolant changed the oil, trans fluid, rear end, front diff, rear diff, and transfer case fluid. replaced them all with synthetics fixed a vacuum leak replaced the rear brakes added a leaf to the rear all new shocks went in.
And its like new. had it for about 20k now it runs good pulls more than its weight.

 

[brendank]

problems:
OHV Engine.
-cracked heads
-intake gaskets split fill oil with coolant takes out bottom end
-rocker arms and push rods wear into each other and rattle bad
-rear of intake gaskets leak oil
OHC Engine
-timing chain issues (all 3) cassettes brake, primary gets sloppy, tentioners go bad,
-vacuum leaks at intake all years, and at egr tube.
-heater shut offs go bad overheat happens engine usually junk.
-vibration dampers break engine vibrates bad takes out main bearings
-just a few examples.
-pain in but to work on.

poor design when went to ohc engine. when it was a ohv engine it was based off 2.9l engine. when went to ohc it was a completely redesigned engine, instead of going to the modular engine (4.6, 5.4, 6.8) design, they design the pos we are stuck with today. could have had a 6.8 v10, take off 2 cyls have a 5.4 take off 2 more have a 4.0 all intechangeable parts (pistons, rods, front cover, basic engine design but they went a different more expensive route, the modular engines by then were developed and good. they had to recast the block to accodate timing chains front and rear with a jack shaft and some a balance shaft, the modulars have 2 chains both up front much better design and easier to work on. plus now with the 4.0 to time it properly you have to spend $500 in special tools for all the holders and aligners and it is quite a project if you dont do it all the timme and it is too easy for something to slip. modulars mark the chain the way in the book telss and line up the marks no special tools need. i think it was a poor shot at a redesign engine
just my 2 cent

Good Lord. Do you realize that your poor spelling and grammar really take away from the validity of your opinion? That's the first thing that I look for in a post. If you're a mechanic who can't do things that are supposedly learned in grade school, then why would anyone take your opinion seriously?

I'm not trying to be a dick. Just pointing it out.


I think the 4.0L OHV is a great engine. Heck, I've done everything to break it, short of running it without coolant or oil.

 

[delcogod]

I just turned over 228,000 miles on my 97 4.0. It still gets 20 mpg and has only had VERY regular maintnance. The intake gasket has been replaced and the EGR system replaced. Thats it. Its driven 75+ miles five days a week. Great engine!

 

[jsoluna]

Reliable engine, in my opinion, but not perfect. I have the early OHV version and I have a little valve noise when the weather's cold and on initial startup, but quiet as a mouse with 125k on the odometer. I did have to replace the lower intake gasket and I still have a horrible oil pan leak, but as long as I keep an eye on all the fluids, it's good to go.

Decent low end torque, good gas mileage (I get 18-23), smooth running engine (except at idle - I've been told they all miss a tad at idle).

 

[90xlt]

1990 210K Still Kickin

Great engine - change the fluids and it will last almost forever. Going on 19 years