Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Timing belt replacement by vehicle age vs mileage?

Should timing belt replacement be based on actual mileage or how old the vehicle’s belt is? Most vehicle maintenance in general mentions whichever comes first.

I’ll have to confirm in the user manual tomorrow, but seems the Hyundai recommendation (as offered by mechanic shop) says timing belt replacement at 48 months or 60k miles (37500 miles under severe conditions). I have a 2009 Hyundai Accent bought new from dealer (in another state).

The car only has bit over 26k miles now, and just went past 4 yr mark of usage. I’m just wondering should I have belt replaced when it hits near 60k (likely another 4 yrs or more) or is the part old enough to warrant replacement even though it hasn’t hit the mileage yet. I’m hoping replacing by actual mileage is ok & that that is the real recommended approach.

The answer depends on your comfort with gambling that you won’t inflict $$$ in engine damage if the belt breaks, or the belt won’t break when you’re on the interstate on a dark rainy night between two trucks.

The rubber in timing belts does break down with age. Does it break down enough such that the belt will definitely break in a 4 yr old car with low mileage? No one can answer that for you.

The ramifications of breaking a timing belt are pretty steep. Many do follow only mileage for replacing the belt (ignoring age) and they get away with it. It is a gamble though.

You should follow the “whichever comes first” logic. It does seem odd to me that the change interval is so frequent. Something like 100K miles and maybe 7-8 years seems more normal these days.

But I guess it is what it is. What JoeMario is referring to in terms of inflicting big $$ damage, btw, is that I’m pretty sure this car has an “interference” engine design. That means that if the valves and pistons are not kept in time (which is what the timing belt does) they will crash into each other. This generally bends the valves and can damage pistons. In other words - a broken timing belt on this car can destroy the engine.

Note that it is pretty rare for a timing belt to give any warnings or show any signs. The car just goes from fine to dead in the blink of an eye. In addition, not only is it difficult to inspect a timing belt (often involving about the same labor it takes to change one), you can’t really tell a whole lot by just inspecting one either. So your safest bet is to just follow the maintenance schedule.

Manufacturers tend to be very conservative on timing belt replacement intervals because if it fails, catastrophic damage will result on interference engines.

For comparison, I have a '99 Honda CRV with an interference engine, and a recommended timing belt interval of 105k mi/ 7 yrs.

Rubber chemistry is quite good these days, and a timing belt is not going to fail due to age at only 4 years. Why does a new Hyundai have a recommended interval of just 4 yrs when an old Honda has a recommended interval of 7 yrs? Did rubber belt technology get worse over the last 10 years? I doubt it. Hyundai is just being extremely conservative.

If it were me, I wouldn’t start to worry about age effects until around 7 years. But that’s just me.

I’ve given this example before but I’ll mention it again. My neighbor’s Kia Sedona suffered a drive belt failure and I agreed to replace it for her. I decided to check every belt including her timing belt. I pulled the timing belt cover off and rolled the timing belt over to inspect it. It snapped off in my hand. I replaced it along with all the drive belts and the tensioner and pulleys. The vehicle was about 10 years old at the time so my neighbor got off very lucky. I told her she run right out and get a lottery ticket but she never did get what I meant.

I’m surprised that even GATES, the company that makes more replacement belts than anyone else, suggests 60K miles too. See
I don’t see an age spec listed, but if your owner’s manual suggests it, age may be more of an issue. .

Gates never lists the time - which I’ve always thought is very odd.

The auto manufacturers limits are meant as whichever comes first. If you don’t put on many miles, obey the time limit. Replacing a belt is a lot less costly than replacing an engine.

I agree with jtsanders. Whichever comes first. My timing belt needed replacement at about four years, too. Drive belt was replaced at the same time. Mine is a 2002 Hyundai Accent which is still going strong at 66,000 miles. If it would only last forever. . . 32 mpg around town, 38 on the road, a manual transmission.

“Whichever comes first” is definitely implied.
As already stated, it makes no sense to push your luck.

Look at the production tag on the door jam and odds are you will find that the car was likely manufactured in the summer or fall of 2008. This means it’s about 5 years old and environmental factors such as extreme cold and heat play a part also.

Gates never lists the time - which I've always thought is very odd

Gates also recommends a 60k mile interval replacement…even when the manufacturer says 100k miles replacement interval.

Gates’ incentive is to sell as many belts as possible.

Carmaker’s incentive is to sell as many cars as possible, and if you can advertise that your car needs less maintenance (ie longer service intervals) than the other guy, you have a market advantage.

Different incentives = different recommendations.

There is more to the story than just rubber compounds, but that would be a long discussion. Anyway, if you open the glove box, somewhere inside it will be a preventative maintenance schedule that tells you how often the oil should be changed, when new spark plugs are needed etc. In that schedule you will find the recommended interval for the timing belt, in miles and months, whichever comes first.. This is what you go by.

It seems that I read somewhere that this engine was originally a Mitsubishi engine and that Mitsubishi sold the factory, molds, tooling and design rights to Hyundai. If that is true, the Mitsubishi had a reputation for the belt breaking at 61k miles or 49 months, especially in very cold weather, and its an interference engine so major damage is done. On the plus side, it was a pretty easy belt to change so it doesn’t cost as much as say a Honda.

A cousin of mine is a mechanic in a Hyundai dealership. He said Hyundai 4-cyl engines in the mid 2000’s were tough on timing belts, with some not making it to their 60K change interval. The 6-cyl engines were fine.

I don’t know recent vintage Hyundai 4-cyl engines are still has hard.

"Gates also recommends a 60k mile interval replacement…even when the manufacturer says 100k miles replacement interval. "

Mmmmmm…maybe they list things differently in different places. But I have a pdf copy of the master belt replacement guide from their website. The recommended mileage clearly varies according to car model. Anything from 60K and up. Plenty of cars in there listed at 100K or over.

They list my '97 Escort as “Inspect at 120,000, replace if needed.” It’s true - I don’t get that, but IIRC my manual doesn’t actually have a change interval. I can’t remember if it says to inspect at 120K or not. I just though it was so dumb that I decided I’d do 100K (which I easily surpass within 7 years - even though the manual lists no time either). Of course an Escort is a non-interference engine. And yes, I know that Gates lists it as an interference. But it’s not.

Anyway, everything I’ve seen from Gates suggests that they pull their info from the manufacturers.

If it says “whichever comes first” in the manufacture’s maintenance schedule, do that. After all, they were the ones that designed and built the car. They should know. If you have doubt, no harm to stop by a dealership shop, see what they think.

A few years ago I considered installing a Gates racing belt, which they advertise as being 3x stronger than their regular belt, in my CRV. But I couldn’t get any belt life data from Gates on it. Since it’s a racing belt that they assume people will beat on, they don’t give you any indication how long the belt will last in “normal” use. Presumably it’ll last at least as long as the regular belt, but it’s anybody’s guess.

I asked around on this forum if anyone had experience with the Gates racing belt, and nobody did. So I didn’t go any further with the idea.

Gates website also recommends six years for everything but doesn’t put it in the charts. I have seen a 48 month recommendation from Canadian sites. Maybe cold weather is hard on belts.

Both age and miles are considered, the priority between the two is “whichever comes first”. I’ve not seen 48 months as a common time interval. 48 months is only 4 years. Every 6 years is pretty common, with some 7, and 8 year intervals. Find that owner’s manual for your car, but I think the time interval will likely be 5 or 6 years in this case.