Everyones Opinion on the 4.0L

[xtremeRanger]

Whats everyone's opinion on the 4.0 im running the 2.9L and im wanting to retire it soon. i have had the thoughts of the 302 swap and now im thinking about the 4.0L

 

[2manyfords]

4.0L is an excellent truck engine, great low end torque and will out work a 2.9L in every situation.

 

[JoeCanada]

Loved mine until the heads cracked but that thing had no problems hauling a 2000 lb boat in and out of the water on a fairly steep boat launch.

 

[jax4bangin]

Loved mine until the heads cracked but that thing had no problems hauling a 2000 lb boat in and out of the water on a fairly steep boat launch.

iv never owned one but iv herd more than a few of these storys

 

[bobbywalter]

its an excellent engine.

 

[Ozwynn]

I regularly towed #5000 pounds behind my 91 explorer, no lack of power. even with the stock A4LD, 3.73 L/S, and 31's it did fine. best Crappy German V6 Ford ever got a hold of.

 

[xtremeRanger]

Why have i heard that they are not good engines. Ex. Head Gasket failure quite often.

 

[dogboy]

Personally, I've never heard of them being a "bad" engine. Sure the head gaskets may blow, or crack a head, which isn't SUPER common, but not uncommon.
They are an awesome, strong running motor in my opinion. They are also durable too. A lot of people have over 300K miles on the 4.0.

 

[JULIUS]

I've had my 2004 4.0 4x4 ext.cab for 2 years excellent power, gas mileage is ok.Love my truck,no problems.

 

[Twizzler09]

Might be an exception.... but I've had my 4.0 overheat several times due to exploding water shutoff valves but it has yet to blow out a head gasket or even crack a head or anything. 213,000 miles and going strong, runs like a bat outta hell. I'd wager that it probably has another 100k left in it, maybe even more. Compression is still right where it should be, at factory specs, like it was brand new!

In my opinion (for what its worth) the 4.0L is a very respectable engine.

 

[xtremeRanger]

So is it worth a 4.0 swap compared to a 302 swap?

 

[Ranger44]

Whats everyone's opinion on the 4.0 im running the 2.9L and im wanting to retire it soon. i have had the thoughts of the 302 swap and now im thinking about the 4.0L

I'd go 4.0. I've driven a 2.3, 3.0, and 4.0. The 4.0 has nice pull, and pretty good power. Doesn't bog on the feeway like the 2.3. A 4.0 is going in place of my 2.3.

Why have i heard that they are not good engines. Ex. Head Gasket failure quite often.

One thing to understand is that on here....most people usually only post a thread when they have a problem. There are a few million 4.0's on the road. So what's a few hundred posts versus that? The heads tend to crack mostly the 90-92 casting due to posterity problmes and a thin casting, and usually only when the engine serverly overheats and/or the cooling system was neglected on other years. I just pulled heads off my 93 4.0 and they are just fine.

So is it worth a 4.0 swap compared to a 302 swap?

A 302 swap will be more intensive and requires alot more fab and custom parts, esp. when it comes down to exhaust etc. A 4.0 swap is basically drop in/ bolt in if you grab everything from the donor.

 

[JoeCanada]

The heads tend to crack mostly the 90-92 casting due to posterity problmes and a thin casting, and usually only when the engine serverly overheats and/or the cooling system was neglected on other years. I just pulled heads off my 93 4.0 and they are just fine.

I would agree. If you take care of it, and do regular maintenance (ie. check all your fluids on a regular basis), don't let it grossly overheat consistently, I'm sure it'll last (almost) forever. I know there's some ppl on here with 300,000+ mile engines. My truck had been through the ringer when I finally got it, the PO didn't take good care of it at all, so it's no wonder the heads cracked.

 

[liquid10]

Try to get a newer SOHC 4.0. My new (to me) 04 has that motor and it is great. Same stump pulling low end torque of the pushrod 4.0, but unlike the pushrod 4.0 it pulls hard all the way to 5,000rpm. gets slightly better fuel mileage too.

 

[jeffro184]

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. the 302 i would say is a more reliable engine and you would be pleased with the power. i have an 88 with a 91 mustang fuel injected engine with some mods and i love it all the power you need. 4.0 are doggy for what they are. just my 2 cents also forgot befor my truck was lifted i was pulling 18-20 mpg which is about the same for a 4.0 i would say its a no brainer