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Can You Put A V8 In A Hummer H3?

The standard V6 engine that the Hummer H3 came equipped with gave this machine ample power. But some might be looking for an upgrade. If you are wondering if you can put a V8 engine inside one of these vehicles, we can help. We researched the Hummer H3 in depth so you'll know for sure if it can be done.

The Hummer H3 can be equipped with a V8 engine. This model had this engine available as an upgrade from the manufacturer as well, making it possible to find a used H3 on the market that has a V8 under the hood.

Now that we know that the Hummer H3 can be equipped with a V8 engine, we'll take a look at the specs of this vehicle so you'll know what's under its hood. You might also be wondering if the H3 is bigger than the H2 or if the Hummer is reliable. For the answers to these questions and more, read ahead in this post to see what our research has uncovered.

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What is under the hood of the Hummer H3?

Beginning with its first production year in 2006, the Hummer H3 came with an inline 5-cylinder engine. Its 242-foot pounds of torque helped to propel this machine and its five-speed manual transmission. With subsequent releases of this model, the H3 would have more than just one trim level and engine option.

white north american frame SUV Hummer H3

The next production year saw a total of five trim levels the consumer could select from. While the base model, Adventure, Luxury, and H3X still kept the inline-5 engine, the top-tier Alpha trim was built with a V8 engine.

These offerings continued along these trim levels throughout the production of the Hummer H3 until the manufacturer ceased making them after the 2010 model year.

It's not hard to find a Hummer H3 with a V8 engine. But if your prospective H3 has the inline 5-cylinder under the hood, it's possible to replace it with the more powerful V8. Conversion kits can be purchased, and you can get an experienced mechanic to put this choice engine inside your vehicle. 

Which is bigger, the Hummer H2 or the Hummer H3?

When most people think of a Hummer, they get a picture of a steel behemoth on wheels, rolling along the roadways and dwarfing the other vehicles on the road with its sheer size.

The two production models of the Hummer that were meant for the consumer were the H2 and the H3. Studying the specs, it's clear that one is a bit bigger than the other.

The H3 measures 187.5 inches long and 85.0 inches wide. It stands 73.2 inches tall. This is noticeably smaller than the H2.

Hummer H3 measurement

The H2 takes the tape to 203.54 inches and is a little narrower at 81.22 inches wide. This model is a bit more off the ground, at 77.83 inches tall.

Hummer H2 measurement

Is the Hummer a reliable vehicle?

Along with safety, reliability is among the top attributes consumers look for when selecting a new or used vehicle. A car or truck that's always in the shop for repairs doesn't bode well for folks that commute or use that particular vehicle for hauling around family members.

Red SUV car Hummer H3 is staying parked near entrance to city yacht port

Those who are considering the Hummer H3 will find that it sits in the middle of the pack as far as being able to count on it.

U.S. News and World Report gave the 2010 H3 model an overall rating of 7.5/10.0. The poor fuel economy and lower safety scores were a detriment to the ratings from this consumer reporting agency. This outlet ranked this model 144 out of 172 for used SUVs under $20,000.

J.D. Power and Associates rated this same model 3.0 out of 5.0 just in the reliability category.

How long will a Hummer H3 last?

We established earlier in this post that the Hummer H3 has average reliability. But assuming that it is well-taken care of, you might be wondering just how long this model can last on the road. Whether you are a current H3 owner or looking to buy one on the used vehicle market, this is handy information to have.

Experts maintain that this vehicle should last well over 200,000 miles. Even though there might be some costly repairs along the way, you can expect the H3 to still be purring along the highways for 15 years or more after it was built (assuming you drive it 15,000 miles a year).

Some consumers have maintained that their H3 odometer ticked over the 300,000-mile mark, making it one of the longer-lasting trucks available.

Getting this vehicle to these higher mileage milestones will mean a good amount of work on your part. Routine maintenance is a must, so be sure that if you are getting a used model that it has been taken care of.

Oil and filter changes, routine inspections of the belts, hoses, timing chain, and more are critical pieces of maintenance that must be performed to help this machine rack up those miles.

Why did they stop making the Hummer H3?

The Hummer was being produced at the beginning of an awkward time for vehicles that had sub-standard fuel economy.

When the recession from 2007 began to slowly make consumers tighten their belts and watch their budgets, the demand for full-size SUVs and gas-guzzling pickup trucks began to quickly wane. What looked to be a feather in the cap for GM quickly turned into a model that was racking up losses year after year.

General Motors attempted to sell the brand to manufacturers in China in 2010. After this deal fell through, the automotive giant made an announcement. The production of the H3 would cease.

But Hummer hasn't finished altogether. It was recently announced that this brand was back in a big way, as General Motors began producing an all-electric version of the Hummer. No matter how high gasoline prices get, consumers will be able to get the Hummer they used to enjoy without paying through the nose at the pump.

Is the Hummer H3 good in snow?

Hummer H3 on a snowy road

A vehicle with the size and power of a Hummer should be good in bad weather. With all that torque and a V8 engine under the hood, you'd expect it to be able to plow through piles of snow with ease. And you'd be right.

This four-wheel drive vehicle has a mode that makes traveling in snow and on icy roads even easier. If you put the H3 in 4-Low Locked mode, you'll move along in these conditions a bit safer. This mode is also used for steep hills and rough, rocky roads.

The power of the H3 and its full-time four-wheel drive configuration makes it a great choice for winter driving. Though driving in adverse conditions should be avoided if possible, those who have to drive in them can do so a bit easier in the H3.

What is the model year Hummer H3 to avoid?

Consumers will want to study the experiences of Hummer owners carefully. Getting a vehicle from the worst model year can lead to unwanted issues. After looking at the research, the model year to be most leery of is the 2006 H3.

This model year had more than its fair share of engine problems. Leaking valves and faulty cylinders were widely reported. Faulty head gaskets were also an issue.

There were also various electrical issues with this model. The NHTSA ordered 4 recalls on the 2006 H3. If you are considering it, be sure that all potential issues were resolved by the current owner.

Final thoughts

The Hummer H3 might have rolled off the showroom floor with an in-line 5-cylinder engine, but that doesn't mean that you can't put a V8 under its hood.

Adding more power to this truck will come at a high cost, but some consumers feel the larger engine is worth it. Take care of the H3, and you'll find that it will last for hundreds of thousands of miles. Drive safe!

We hope this post on the Hummer H3 answered all your questions. For more helpful information, we suggest reading the following posts:

How To Set Cruise Control On Hummer H3 [Step-By-Step Guide]

 Do Hummers Have 3rd Row Seating?

How To Install A Leveling Kit On Hummer H3