Timing Belts vs Timing Chains


#1

Can anyone name some cars that have engine timing chains? I understand that timing chains never need replaced but timing belts need replaced as part of regular upkeep but the job is very expensive.


#2

go here http://www.gates.com/part_locator/index.cfm?location_id=3598&go=Interference

you can look up cars by model to your hearts content.

To name a few, I was looking for a new pickup truck Toyota tacoma or tundra. I didn’t buy one. Why? both models use timing belts!


#3

Subaru’s six-cylinder engines use timing chains, rather than timing belts. That is one reason why I opt for their sixes, the other reason being the absence of head gasket issues on the sixes.

However, it is not true that, “timing chains never need replaced (sic)”. While timing chains are very durable components, it is sometimes necessary to change a timing chain after…maybe 150k–200k miles or so. Many will go for the entire life of the engine, but if someone is in the habit of doing a lot of full-throttle acceleration runs, he will wind up stretching the chain. If someone uses extended oil change intervals, it is possible for sludge build-up to compromise the chain’s lubrication, thus leading to an early demise.

Even engine design has a lot to do with timing chain life. Pontiac’s 4-cylinder engine, as used on the early Tempest models, typically needed to have its timing chain replaced every 40k or so. Luckily, just like other timing chains, the rattling noise as it reverberated against the inside of the chain cover was the tip-off that the chain needed to be replaced again.

So, timing belts need TO BE replaced as a part of regular maintenance, and timing chains may need TO BE replaced on an as-needed basis, albeit much less often that timing belts need TO BE replaced.


#4

There are many vehicles out there that use chains; too many to sit here and list.
Chains usually last the life of the engine and car.

The chains that do fail generally fail due to the poor maintenance habits of the car owners. Poor maintenance habits means extended or irregular oil changes, chronically running the oil level down low, etc.
Chains do not like dirty engine oil.


#5

As consumers become more aware of the expense and limitations of timing belts, manufacturers are switching back to chains. Honda is a prime example.


#6

I’ll condense the difference between the two. Timing belts, when they fail, tend to result in very expensive catastrophic failure. Most, not all, of the engines are interference engines and bend the valves when they fail.

Timing chains, OTOH, will stretch as they wear. This will typically show some symptom before jumping time. You can also measure the stretch if you can see both the crank pulley and the cam. It’s read/measured in degrees of rotation at the crank.

Lubrication is critical to a long chain life …and not at all with a timing belt. Each has their technical advantages and shortcomings.


#7

In general timing belts do not last as long as chains, but chains don’t last forever and replacement is expensive.

Timing belts usually call for a change at around 100,000 miles. Over the life of the car the cost is really not much.

Timing belts are generally quieter than chains, but they don’t last quite as long and they usually fail suddenly and without warring, where chains give you more time and usually let you know when they are close to failing.


#8

some dont have both chain and belt. Use gear driven!! For instance Dodge Ram truck with Cummins engine use gear driven no belt or chain. Also I believe older Jeep Wrangler with 4cyl engine use gear driven.


#9

Can a belt make all the bends required for DOHC and then throw on variable valve lift and duration? Have you seen what GM is doing with its “V” engines that have the cam in the normal place in regards to variable valve timing? the device looks like an AC clutch.


#10

I can tell you one vehickle that has a timing chain, I have an 06 honda CRV with a timing chain.


#11

My 1979 Toyota Celica (20R Engine) has dual timing chains. I have 200k miles on the engine, and have had no problems with the chains (this is true for most of the 20r engines). I’m told that Toyota moved to a single timing chain on the 22R engine, and those chains do not last as long.


#12

I had a 1990 Toyota Pick-up with the 22R. I changed the timing chain at 250K miles, but only because I was doing a head gasket replacement. The chain still hadn’t reached it’s stretch limit, but was fairly close.

But, since Toyota hadn’t made the 22R or RE since 1993, your looking at a 17 yo or older truck to get that engine.


#13

Isn’t it sad how things have changed for Toyota? now they seem to have forgotten how to make a valve spring.


#14

Timing belt is ok if you can do the job of changing it and associated hardware such as the tensioner and water pump if applicable.

I agree that a roller timing chain can last indefinitely if you don’t repeatedly take the engine up to redline.

Any current ohc GM car uses a roller timing chain.


#15

My Mazda CX-7 has a timing chain


#16

The 20R motors were produced from 1975 to 1980, and the 22R motors from 1981 through 1995. My 94 p/u has a 22RE. I can’t comment much on any issues with the 20R, but I have owned several 22R and 22RE engines. When the chains on these engines stretched out, they would wear two grooves into the timing chain cover and directly into one of the coolant passages behind the waterpump. If left alone, of course disaster occurs. In my experience and talking with several 22R owners, this occurs around 150 kmi… some were sooner or later, and for some it never happened.

Another issue was that the timing chain guides were made out of hard nylon. Occasionally the driver-side guide breaks causing a jump in time or in extreme cases bent valves…ask me how I know! Kits are available now with new timing chain covers and steel-backed driver-side guides.


#17

I wouldn’t worry about belts vs. chains. If you do the recommended maintenance, there’s nothing to worry about. I have over a quarter-million miles on my engine which uses a timing belt. The belt has been changed twice in my ownership of the vehicle.

But if you ARE worried, I’d look at buying a vehicle that doesn’t have an interference engine, regardless of whether the valvetrain is driven by a belt or chain.


#18

The 2009 Toyota Camary L4 and V6 and Corolla L4 have timing chains.


#19

Most of the new Hyundai (and Kia) engine designs are chains. And they are starting to use sealed auto tranmissions, too. Less maintenance all-around


#20

I hope that you are not interpreting “sealed transmissions” as a good thing.
This will inevitably lead to less maintenance and–several years down the road–more transmission failures.

Making things appear to need less maintenance is not necessarily a positive step.