What Are The Most Common Issues With Ford 5.8 (351 Windsor) Engine?

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Let me make one thing clear; the Ford 5.8 is also called the 351 Windsor. These are two names for the same product. The 5.8 engine is one of the most successful Ford engines ever. It is a small block engine, and users loved it.

Although the engine was discontinued a long time ago, people ran into various issues with the engine.

Some of the main Ford 5.8 liter engine problems are:

  1. Coolant Leak Due To The Timing Cover
  2. Oil Leak Due To The Gasket And The Rear Main Seal
  3. Failure Of The Intake Manifold
  4. Failure Of The Exhaust Manifold
  5. Structurally Weak Cylinder Blocks

As you may have noticed, the engine is not a perfect one. But, I will be elaborating on each of these engine issues, so you can know if the engine is worth buying.

The 5 Most Common Ford 5.8L Engine Problems

The five problems discussed above will be the main focus of our attention in this part of the article. I will be discussing the issue, how it can damage your engine, and what should be done to address them.

Let’s begin!

1. Coolant Leak Due To The Timing Cover

The Issue

Let’s first talk about one of the more common issues with the 5.8 engine. The Windsor features a design in which a cover protects the timing chain.

The cover is properly fitted using a gasket. As is the common case with gaskets, this one starts to wear off slowly. The wearing reaches a point after which there is a coolant leak.

Diagnosis And Damage

A coolant leak is something that starts slow and slowly builds up the pace. You will not notice it immediately, but you will run into various issues when the coolant level becomes too low for the engine to function properly.

The first thing that you will see is that the low coolant light has turned on. It indicates that there is not enough coolant in the engine. There is a chance that you may notice the smell of burning coolant.

Overheating

This can be the case if the engine is overheating. Yes, that is true; if not addressed quickly, you will start noticing that the engine overheats a lot. An overheating engine is not good news.

You can run into several different problems, one of which will I will be discussing below. The engine overheating can cause malfunctions in the circuitry or some other major damage.

Repair

If you are sure that there is a coolant leak in your system, then this is what you should do:

  • Get the vehicle towed to a nearby mechanic.
  • Get the coolant level checked.
  • Replace the gasket for the timing cover.

After everything has been completed, you still need to be on the lookout for a coolant leak, which may be due to another source. If not, then you are good to go.

2. Oil Leak Due To The Gasket And The Rear Main Seal

The Issue

As expected with Ford engines, there is another problem of unexpected oil leakage from the engine. The victim, in this article, is the 5.8 engine.

As is the case with engines as old as the Windsor V8, the gaskets are prone to breaking and failure at any given time, given that you are still rocking the original. The failure of these gaskets commonly causes oil leaks.

The rear main seal is another source of the problem. On old engines, like this one, the seal can crack and fail. The seal prevents oil from leaking to the rear of the engine, as evident by its name.

Symptoms And Diagnosis

Fortunately for all of you guys, an oil leak is something that can be easily caught. You will notice oil leakage at the back of the engine. Plus, it will look like that the engine is consuming oil way too fast.

So, if you have to get a new oil bottle every few months, then I think you have a problem. The simplest way to diagnose this issue is when the low oil light lights up. You should get the issue resolved as soon as possible.

Repair

The gasket replacement is simple and not that labor-intensive. But when it comes to the seal replacement, this is where the bill starts to rack up. The replacement can be done at home, but it is recommended to do it by a professional.

If not, then:

  • You can have another leak.
  • You will have to spend more on getting oil.
  • It will take up a lot of your precious time.

The repair should not be delayed unless you want your vehicle to stay in a non-functioning condition.

3. Failure Of The Intake Manifold

The intake manifold is a part of the engine that is responsible for taking in cold air. It rests on top of the engine block and has been designed to spread the air on all cylinders. This is of paramount importance because the air is used to aid combustion.

The Issue

The intake manifold itself is flawless. It is great at what it does. But the bolts that keep the manifold down have a different story. They cannot handle high temperatures and vibrations. Unfortunately, an engine is a place with a combination of them both. So, the bolts break over time.

The breaking of the bolts causes a vacuum leak, the air that is being dragged in starts to leak. This causes various issues for the engine.

Symptoms And Damages

As you all must know, combustion needs oxygen, which is taken from the air, in this case. When the engine does not get enough air, there can be a rise in several issues. From misfires to sudden shutdowns, anything is possible when the manifold is not working properly.

Some of the commonly occurring issues are:

  • High fuel consumption.
  • Hesitation while accelerating.
  • Rough idling.
  • Cylinder misfires.

These are some of the many issues that can arise, thanks to the breaking of one bolt.

Repair

So, what can a person do to get the repair done? Fortunately for all of you guys, this is the easiest repair on the entire list. You only need to replace the bolt with a new one, and you are good to go.

You should still check for any problem with the manifold itself, such as damage, to rule out any other possibilities.

4. Failure Of The Exhaust Manifold

Coming up next on this list of common Ford 5.8 engine problems is the failure of the exhaust manifold.

Function

The exhaust manifold is the first part of the whole exhaust system. It has been designed to collect all emissions from the engines and then forward them to the exhaust system. Without a proper exhaust manifold, there won’t be a proper breakdown of toxic emissions, leading to future problems.

The Issue

The exhaust manifold itself has the same issue, unlike the intake manifold, whose bolts are susceptible to varying conditions. The manifold is made out of cast iron. If you know a bit about it, you may know that iron can easily expand and contract.

Unfortunately, the engine has varying temperature conditions. Plus, the vibration of the motor helps in the process of making the manifold unusable.

Symptoms And Damages

So, how can a person identify a failing exhaust manifold? I have got the perfect answer.

You should check for these things to confirm your suspicion:

  • Check for exhaust noise in the vehicle.
  • Observe if there is an unpleasant smell in the vehicle.
  • There is a sudden power and acceleration loss.
  • The fuel consumption has taken a hit.

Out of all of these possible diagnosis sources, the first two are the ones that confirm the failure of a cracked exhaust manifold. Various issues can cause the other three. But if all three are happening at the same time, then you have an exhaust manifold issue.

You have two repair options. You can try to find a new exhaust manifold or upgrade to an exhaust header made from steel. It is more durable and can also result in an improvement in horsepower.

5. Structurally Weak Cylinder Blocks

History

The final issue in this article is a design fault in the 5.8 engine. There is no doubt that the Windsor was and is an astonishing engine block. The 1969 to 1971 era was the best, with the highest quality of materials used.

The components were thin and were not as structurally sound like the old generation. Since 1975, the company started using lightweight materials to create a lighter block.

The Issue

There is not much to talk about here. When the company started using lighter materials, there was a noticeable drop in performance too. For comparison, the original blocks could easily handle 1000whp of power levels, while the newer ones could reach the 650whp mark. That is a pretty massive difference.

The newer blocks were also not as structurally sound. So, Ford had to drop the power rating of the engine.

What To Check

Regardless of the power difference, there is no huge difference you will see when you drive any one of the two engines. Plus, most of the existing ones have been modified for higher and better performance.

Still, there are some things that you should keep in mind when driving this engine:

  • Don’t cross the 650whp mark.
  • Keep the engine temperature in check.
  • Keep the engine regularly maintained.

These three checks will ensure that you get the maximum life out of your 5.8 engine. The 650whp mark is more than enough for most people. If you are looking to go over the limit, then it is advised to prepare the engine to handle such load.

What Is The Ford 5.8 Engine?

The Ford 5.8 engine goes by the name of Windsor V8. That is not an official designation, but users started calling it that. The small-block engine was built by the company from 1961 to 2002.

That is four decades of production. This alone tells you if the engine was good or not. The engine was also considered to be one of the best Ford engines. The engine could output a respectable 250 HP.

This is to be expected with a small block engine. It was focused more on better acceleration and handling. Recent advancements in technology have made them just as good as big-block engines.

Overall, the engine is an excellent one, and no one can tell you otherwise. It does have its fair share of issues, but fortunately, they are all fixable. So, you don’t need to be frustrated if any of these issues occur in your vehicle’s engine.

Is The Ford 5.8L Engine Reliable?

This is an excellent question. Yes, the engine is super reliable. Users have used this engine for years, and they ran into little to no issues, apart from the five I listed above.

So, if you decide to buy the engine, I can assure you that it will exceed your expectations. But, if you get the 5.8L engine and have some spare cash, I recommend that you get the gaskets and the seals changed, just as a precautionary measure.

The 5.8L engine’s reliability is so good that it can easily touch the 300000-mile mark, given that you regularly maintain the vehicle. If not, then the engine will start giving you issues around the 150000-mile mark.

In case you were wondering, an engine has specific needs, just like a pet. So, for it to work without any quirks, you need to fulfill its requirements.

What Car Uses The Ford 5.8L Engine?

The first vehicles to feature this bad boy under the hood were the Galaxie and the Mustang in 1968. The Mustang used the engine for only two years while the Galaxie used it for six years, with the engine last seen in the 1974 model. In 1969, several vehicles were released with this small block engine.

They were the Mercury Cougar, the Country Squire, the Fairline, and the Torino. Out of these four, the Country Squire used the engine until 1991, which was the longest period of any vehicle with the same engine.

The Mercury Cougar station wagon, once again, debuted with the engine in 1977. The Mercury Colony Park, the Marquis, the Grand Marquis, and the Continental Mark VI were some of the last few vehicles released alongside this V8 engine.

Other vehicles that rocked this beast were the Ford Elite, the E-Series vans, the LTD and LTD II, the Thunderbird, the Ford Bronco, the Crown Vic, and the highly popular Ford F150 F250 and F350 trucks.

Ford 5.8L engine Specs

Chamber head composition Cast Iron
Chamber head composition Cast Iron
Fuel Gasoline
Fuel injection type Carbureted
Arrangement 90-Degree V8
No. of chambers Eight
Valves in each cylinder Eight
Bore 4.00 inches
Stroke 3.50 inches
Displacement 5.8L or 5812 cc
Internal combustion engine (type) Naturally articulated
Compression ratio 11.0:1 -1969 8.8-1 – 1971 onwards
Power 300HP at 5400 rpm – 1969 161HP – 1972
Torque 380 lb.-ft @3400rpm 325 lb.-ft @ 2800 rpm
Weight of engine oil SAE 5W-20
The capacity of engine oil 6 quarts w / filter
Firing directive 1-3-7-2-6-5-4-8
The interval between oil change 5000 miles (8000km) or six months

The Benefits Of Choosing The Ford 5.8L Engine

There is no doubt in my mind that the 5.8L is a superior engine. Unfortunately, that is not the case with every single reader of this article. That is why I will be outlining some of the advantages of owning this engine.

  • Most problems are easily repairable.
  • Made out of very durable cast iron.
  • Older models can output a decent 300 HP.
  • It can easily cross the 300000-mile mark.
  • The engine will require very little work.

FAQs

How Long Will A 351 Windsor Last?

If you never cross the 3000-rpm limit, which almost no one does, you can expect the engine to wear out after 300000 miles completely. But, you will get the engine in used condition to expect less mileage from it. This must be kept in mind when purchasing it.

How Much Does A 351 Windsor Engine Cost?

Due to the engine being quite old, its price is quite low. An engine with a decent and rebuildable condition should not set you back any more than a maximum of $500.

If you are getting one at a higher price, then I am sure that you can do better. Being such an old engine, you will have to spend a pretty penny to get it up in good condition.

What Is The Fuel Consumption Of The 351 Windsor?

Being a V8 engine, it requires more fuel than normal. Ford still optimized it excellently. In the city, you can expect to have a 12-mpg average, while on the highway, you can increase the number to 15. This is more than decent for a V8 engine.

What Year Is The Best 351 Windsor?

Although the entire 41 years of the engine were spectacular, a few were a bit more powerful than the others. The 1969 to 1971 models of the 5.8L engine are the ones that are classified as the best ones out of the bunch.

Conclusion

The Ford 5.8 engine is far from being 100% fault-free. But it is one that was taken positively by thousands of people. A V8 engine is almost always impressive, but this one took things up a notch.

We talked about the common Ford 5.8 engine problems in this article. I listed five of the most common ones that frustrated users. If you have finally decided to get this bad boy, I must congratulate you because it is one of the best decisions you will ever make.

No matter what you read online, the hands-on experience is completely different, and this one will exceed your expectations.