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V8 vs V6's - Engine longevity/maintenance issues

Generally, any significant maintenance related issues comparing a V8 to a V6, over say a 100,000 mile lifetime ?

Pretty much any engine should last 100,000 miles from new. Things to keep in mind:
V8’s generally use more gas than V6’s.
V8’s will generally have larger oil pans and require more oil during changes (but not always).
V8’s have 8 sparkplugs instead of 6, this will be important at around 60k miles or whenever your recommended sparkplug change is.
V8’s and V6’s both have 2 head gaskets due to the v shape.

In my opinion, the fewer moving pieces there are in an engine, the fewer pieces there are to break.

If you are towing however, I suggest getting the bigger engine. Bigger engines have more torque and it is better to get a bigger engine and run it normally when towing than having a smaller engine and running it hard.

Back in the late 1940’s through the 1960’s, an overhead valve V-8 engine was considered the engine of choice for durability, particularly if highway driving was involved. Consumer Reports had, in its auto issue, a table of specifications that included piston travel per mile in high gear. These overhead valve V-8 engines were usually coupled to a higher geared (numerically lower) rear axle and theoretically lasted longer than the inline long stroke 6 cylinder engines of that time period. In the late 1950’s, one of the top used car ratings by Consumer Reports was the Cadillac.
When the V-6 configuration came along and was refined, it rivaled the V-8 in durability. Metallurgy also improved, so today the number of cylinders is a matter of choice and durability really doesn’t depend on the number of cylinders. I really don’t think that the cost of 2 more spark plugs for a V-8 engine is significant.

Fuel mileage depends on a lot of factors. I remember in the early 1950’s, a Cadillac with the overhead V-8 and the 4 speed GM Hydramatic transmission got better mileage than an early 1950’s Chevrolet with the inline 6 cylinder engine and the PowerGlide automatic that depended on a torque converter as opposed to gears.

If you are considering a Hyundai Genesis, which you have tagged in your post, many publications which have tested the car agree that the V6 has more than enough power and the V8 is overkill. Durability with either is not expected to be a problem as neither engine will be strained to move that car. The V8 will definitely use more gas than the V6. The main advantage to having the V8 in this car would be if you intend to install an aftermarket exhaust system and want it to sound good. Maintenance wise, the V8 will likely be more expensive to maintain in terms of more parts to replace on a routine basis and more labor to replace them.

Triedaq, didn’t the 4-speed GM hydramatic have a torque converter??

The more moving parts you have the higher the ownership will be. Longevity isnt really an issue anymore…they will last the same if maintined properly. Everything costs more with the increase in cylinder numbers

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A turbohydramatic has one but maybe that other one didn’t.

I was curious and had to look. EPA figures show 1 MPG less for the V8.

I disagree that the difference between a v6 and v8 will be serious over its life in terms of maintenance. It may be the v6 has a timing belt and the v8 has a timing chain. I don’t think broad generalizations apply.

I’ve had two V6’s last well past 300k miles…Owned 2 4-cylinders last over 300k with one lasting past 400k miles. Number of cylinders has nothing to do with it…How well it’s designed and manufactured along with proper maintenance is the key.

So then you just agreed with me? More moving parts is related to the OWNERSHIP COSTS OVER THE LIFE OF THE ENGINE…more parts…more oil…more fuel…more parts to replace…etc

I also stated that they will last the same depending on equal maintenance.

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Most important factor is maintenance. Follow Hyundai’s recommendation for maintenance and don’t skimp on it. If automatic transmission, make sure you change the fluid like lever 30,000 miles. (not a flush, drain and refill and clean the filter (if fitted with one).

The GM Hydramatic did not have a torque converter, but instead had a fluid coupling. The difference is that there is no torque multiplication with a fluid coupling as there is with a torque converter. In 1961, GM did come out with a revised Hydramatic that was called the “slim Jim”. It had a torque converter, but the number of speeds was reduced from four to three.

Chrysler products used a fluid coupling in the 1940’s and into the 1950 except in the Plymouth line. On some models there was a three speed manual transmission behind the fluid coupling. The car could be driven just like any other three speed manual, but you did not have to put the clutch down to prevent the engine from stalling at a stop. You could start in high gear as well, but the acceleration was dreadfully slow. There was also a semi-automatic “lift and clunk” transmission that had two driving ranges–low which incorporated a first and second speed and driving range which incorpated the third and fourth speed. One normally used the drive range. The car started in 3rd and when one reached at least 15 mph or more, the accelerator was released and the transmission dropped into direct drive (fourth speed). Starting in 1951, some Chrysler products did offer a torque converter backed up by the “lift and clunk” transmission. This did offer better acceleration since there was torque multiplication. However, the engine and torque converter shared the same oil which led to problems. To further add to the confusion, Plymouth offered “Hy-Drive” starting with the 1953 models. This was a torque converter backed up by a three speed manual transmission. Again, this torque converter shared its oil with the engine. This set up was a disaster and was phased out in 1954 when Plymouth offered the PowerFlite automatic that was also made available in the rest of the Chrysler line. This was a 2 speed automatic transmission with a torque converter that did not share its oil supply with the engine.

The point is that a fluid coupling and a torque converter are not the same thing. They serve the same function, but the fluid coupling offers no torque multiplication.

Back in the 1930s when the manufacturers made real cars, Lincoln had a V-12 engine and I believe Cadillac had a V-16. I don’t know when the V-16 disappeared, but the Lincoln V-12 was used through the 1948 models. V-8 and V-6 engines are wimpy engines–not enough cylinders. There isn’t much to choose between these two engines.

The late Ed Cole, chief engineer for Cadillac at the time admitted that the V16 Cadillac (which he designed) “was a dog!”. So much for “real” cars. The only saving grace these big gas guzzlers had was that they were SMOOTH. Another dog Ed Cole produced was the Corvair pancake air cooled 6, with numerous cost-cutting shortcuts.

However, those depression luxury cars did have good bodies and quality chrome work and upholstery.

As MikeinNH so eloquently states, the quality of design and manufacture, plus good maintenance determine the life of an engine. Volvo and Mercedes, and Peugeot in France were the first companies to make 4 cylinder engines that would last as long as 6 or 8 cyinder ones. Then came the Japanese, who rewrote the book on small. long lived and reliable engines.

The Lincoln V-12 was also a real dog. This engine was prone to oil burning at relatively few miles on the engine. This V-12 was often swapped out for a Ford truck V-8. In fact, when the 1949 Lincoln was introduced, it did use a version of the flathead Ford truck V-8 in place of the V-12.

I did own a 1961 Corvair wit its pancake air cooled 6. My Corvair ran great. However, Ralph Nader missed the real problem with the Corvairs produced after 1960. The seals between the cylinders and the block would leak fumes into the heating system. There were reported cases of carbon monoxide poisoning with the Corvair. The 1960 Corvair avoided this problem by having a gasoline heater. Of course, the gasoline heater cut deeply into the gasoline mileage.


Sorry for all the screaming but…My God what were they thinking? I agree that Ralph Nader missed the mark now that I have heard of this. Un-friggin-real. A constantly lit pilot light too? All fueled by gasoline…OH MY GOD… I am never going to forget this as long as I live and I am shocked that I never heard of it. I’m totally BLOWN AWAY

I think that at one time they were pretty common.

Back in the 1940’s, a heater was an option on most cars. The Stewart-Warner company made an aftermarket heater called the South Wind. It was a gasoline heater. As I remember, you pushed in a knob that powered an ignitor that got the heater going.

The 1960 Corvair heater was a factory installation and was all that was available that year. The 1961 and later Corvairs had hot air heaters where the hot air came off the exhaust manifold.

It seems to me that in the late 1950’s, Chrysler Corporation may have offered a gasoline heater as an option.

If my memory serves me right, I seem to recall gas heaters as being common in the old air-cooled Beetles too.

Lots of things that were common the the past would be today comsidered dumb and risky. This applies not only to automobiles, but also (and maybe more so) to industry.

Back in the late 1970s during the OPEC gasoline shortage, an electric car came on the market that had the Citicar brand. It had a propane powered heater. Consumer Reports tested the car and found that this propane heater caused the windows to fog up badly. My guess is that these heaters weren’t vented.

I remember very well the old days of unvented gas space heaters used in homes. I think they are off the market and are illegal. Servel, until it went out of business in 1957, manufactured a gas refrigerator. It had no moving parts and would last practically forever. Unfortunately, it has been found if the burner becomes partially plugged, the refrigerator puts out carbon monoxide. I read where the government is now recalling these Servel gas refrigerators and if you turn one in, you get $100 for it.