Spark Plugs - OEM. UK 60k but US is 120k - Why

[Kojac]

 

Car went in for a service at 60k about 2 years ago (Toyota Dealership).

Spark Plugs are OEM.

Toyota standard service schedule (UK) - REPLACE SPARKS AT 60k

It was not done. I asked why. The service manager said "no point in changing if not yet needed".

 

A) Why do the sparks need changing at 120k in US, but at 60k in UK.

B) Also - was the service manager right. 

Car in now on 80+ K.

C) Should I change them?

 

This topic is meant to be an exploration of the topic, that through a deep-dive discussion, will help increase our knowledge and understanding of the issues at hand.

 

K.

[FROSTYBALLS]

Servicing requirements are usually based on what the market needs. Different driving conditions, market (including what is normal replacement times for similar vehicles) and climate in the US probably influenced service requirements put in place by Toyota US. In Europe, European service requirements differ to those in place in the UK - 1 year/15,000km for Europe, 1 year/10,000 miles UK (obviously influenced in the UK's case by the use of miles rather than kilometres).

Bear in mind that in the US service intervals are 6 months/5,000 miles.

Presumably the service manager saved you some money/delayed some expense for you after the plugs in your car were examined and deemed to still be OK at the 60,000 service.

[flash22]

The US never got the hybrid Corolla, 2010 is the first year of the Auris hybrid

hybrid plugs do last a lot longer, Denso say up to 120k miles, Inspect at 60k

At 80K miles I would change them for peace of mind/preventive maintenance

[TonyHSD]

My first charge ever was at 80k miles , I didn’t looked properly what I need to change at 60k or simply forgot to do it. Anyway, at 80k miles they looked good enough to last more miles , perhaps 120k or even more. However when skipping spark plugs changes may lead to premature coils failure, these are very expensive and I rather do 60k spark plugs replacements. These spark plugs although wearing slow there were signs of wearing out of the side tip more than on the central electrode., which changes the gap and the spark. 👍

[Derek.w]

Some spark plugs have 2 or 3 outer non adjustable contact but then they do last longer.

[AisinW]

American manual for oil change is also 10k miles/1  year but many Americans do a lot short trips and very cold Midwest.  Under harsh condition,  it is also written manual 5k miles.  Normally,  we do 6 months maintenance but only wheel rotation in between oil change.  I think 10k miles in Europe is ok because it is not as cold as Midwest or as hot as Arizona or florida.  

The spark plugs is following Denso rating, 120k miles,  but it drives european nuts with such long time interval.  

Brake fluid 2 yearly interval is excessively obsolete and typically we have 3-5 years recommendation in USA together with transmission fluid change 60-100k miles. 

I opened the spark plugs at 60k miles,  they are perfect and put them back but i may change it at 90k miles. 

[flash22]

US of hay and uk/eu are tuned/mapped vastly differently, fuel quality is a big factor

Plugs should be SC16HR11, if the plugs are original they may be the old SC20HR11 that are known to give issues and kill coils (2ZR-FXE) stick with Denso plugs ,Toyota engines do not like ngk/champion plugs

[FROSTYBALLS]

Extract from the Toyota US website: Online Toyota Vehicle Maintenance and Service Schedule | Toyota Owners

[furtula]

Changed mine when the car reached 100k, they were still fine. They were ~30 GBP 3 yrs ago, and it wasn't that pricey.

  Even the copper spark plugs now have service interval 18k miles, atleast the ones i put in my Yaris, and i noticed most of them were the same, interval wise.

 

[AisinW]

18 hours ago, FROSTYBALLS said:

Extract from the Toyota US website: Online Toyota Vehicle Maintenance and Service Schedule | Toyota Owners

Thanks, it is clear now "...owners who prefer synthetic oil, we recommend an oil change at 12 months or 10,000 miles, whichever comes first. ..."   USA interval is also 10k miles but we still do check up in 6 months interval (tire rotations) and 12 months oil change since 2009 when Toyota started using 0W-20 in Prius 2009. 

Iridium Denso is relatively cheap for €40 a set and they are well made. NGK is also good if we cannot find Denso.  I used Autolite double platinum in 2006, when the head gasket blew up in 2008 in my Altima 02,  30k miles usage, the spark plugs looks fine but one of the platinum tip is missing. It was only pressed or poorly welded not Laser-welded like Denso/NGK.  Autolite and Champion plugs are extreemely cheap, $16 a set for double platinum plugs.  There is no more SC20HR11 because it is superceeded by SC16HR11 (hotter) to avoid fauling spark plugs.  Many 2009-2012 2ZR-FXE in Prius 3 consumes engine oil at the time when the SC16HR11 revision was announced. 

But again, 120k miles is the actual recommended lifespan from the OEM supplier/Denso.  Just like ZF and Aisin recommend 60-100k miles transmission fluid interval although manufacturer claimed it is filled for life = until warranty expired.  The same thing with VW, Opel/Vauxhaul no coolant change interval/filled for life = until you need to replace leaky thermostat or water pump. Pentosin as the coolant suppliers for most German cars stating maximum life is 120k miles for superlonglife and 60k miles for longlife coolant.  Toyota interval for superlonglife coolant is 7 and then 5 years.  Toyota coolant contains phospate and very sensitive to hard water.  Very big problem in mainland europe if we use tap water. That's why most european brands use Silicate instead of phospate additives.  

[loz8]

23 hours ago, Kojac said:

 

Car went in for a service at 60k about 2 years ago (Toyota Dealership).

Spark Plugs are OEM.

Toyota standard service schedule (UK) - REPLACE SPARKS AT 60k

It was not done. I asked why. The service manager said "no point in changing if not yet needed".

 

A) Why do the sparks need changing at 120k in US, but at 60k in UK.

B) Also - was the service manager right. 

Car in now on 80+ K.

C) Should I change them?

 

This topic is meant to be an exploration of the topic, that through a deep-dive discussion, will help increase our knowledge and understanding of the issues at hand.

 

K.

tricky when the car does few miles but my dealer follows service intervals,ie serviced each yr.60k plug change done when car had only done 30kmiles. 10 k miles later I suppose they will be changed again.If I say no ,would it void the 10yr warranty?.

[TonyHSD]

44 minutes ago, loz8 said:

tricky when the car does few miles but my dealer follows service intervals,ie serviced each yr.60k plug change done when car had only done 30kmiles. 10 k miles later I suppose they will be changed again.If I say no ,would it void the 10yr warranty?.

The plugs shouldn’t been changed at 30k miles, they don’t have time intervals like oil change for example 10k miles or 12months whichever occurs first. You better make sure the dealer is not !Removed! you up and charge for work that they haven’t actually done, something that can happen even within the highest ratting main dealer garages. 

[loz8]

I'll make it a point when it goes in again.

[AisinW]

Always ask for the old parts if something has been replaced. Especially electronics. Check the bleeding bolts if the brake fluid is replace, it must be squeaky clean and bright amber fluid on the reservoir. Be vigilant. Any new suspension parts will be very obvious if they need replacement. Ask and see by your own eyes if things need replacement. 

I see no reason to get Relax-Garantie if dealership mark up the price for annual check up like in Germany and France. Oil change for €150 is acceptable but not for €240. That is the cheapest price in 200 miles radius. Some even charge for €440. Spark plugs change for €200 and it is relatively easy, 30 minutes job in Auris with 3/4 14mm socket wrench, a magnet pickup tool, and 20 cm extension. 

[Wooster]

On 12/19/2022 at 4:05 PM, Kojac said:

Why do the sparks need changing at 120k in US, but at 60k in UK

I asked the service manager at 'my' Toyota dealership (Jemca, Croydon) the same question many years ago.  His reply was that UK cars get used for many more short journeys and the spark plugs go through more cold-hot-cold cycles. This can lead to micro cracks in the ceramic insulator, which can lead to coil failure.

[AisinW]

I think that is universal in the world for any hybrid cars.  The only part that sometime fail is the internal resistor, but very rare. The porcelain materials in Japanese Denso and NGK is very tough, none of them ever cracked unless physically damaged from hitting piston. The Iridium tip is very tough and barely have any wear/increased gap.  

The 60k miles interval is just money maker for dealership like 2 yearly brake fluid flush. 

But follow the manufacturer schedule if you are still in 3 years warranty period. Otherwise, do wathever we comfortable with. 

[Konrad C]

I have just found this and want add my recent post to this subject. Things mentioned above probably hide the fact if 'fake' sparkplugs are used. They will not show up unless checked every so often or a problem arises. 

So if you are not sure of the spark plugs, check them!  

[AisinW]

Exactly, that's why we should keep older parts especially electronics including spark plugs.  The gap is nearly identical with thr new plugs after  60k and 80k miles on mine. I check all plugs last year and I put them back. I don't need to take the cowl out but I need 2 short extension and magnet stick. 

Always buy genuine Denso Plugs from known suppliers (Autodoc, Amazon LLC not third party, or local stores). 

  

[TonyHSD]

10 hours ago, AisinW said:

Exactly, that's why we should keep older parts especially electronics including spark plugs.  The gap is nearly identical with thr new plugs after  60k and 80k miles on mine. I check all plugs last year and I put them back. I don't need to take the cowl out but I need 2 short extension and magnet stick. 

Always buy genuine Denso Plugs from known suppliers (Autodoc, Amazon LLC not third party, or local stores). 

  

These plugs look very good. 👌

[AisinW]

I have a picture for 120k miles compared to the new one. Yes, they last 120k miles just like DENSO promised. We all do 120k miles interval since 2010 in almost most Toyota and Nissan in the USA. 

The car burns oil because he did 10k miles interval and use non synthetic oil in Superlube, Tireplus, or Walmart. 

[TonyHSD]

2 hours ago, AisinW said:

I have a picture for 120k miles compared to the new one. Yes, they last 120k miles just like DENSO promised. We all do 120k miles interval since 2010 in almost most Toyota and Nissan in the USA. 

The car burns oil because he did 10k miles interval and use non synthetic oil in Superlube, Tireplus, or Walmart. 

Very good indeed 👍

[furtula]

I guess plugs are to be changed more often same reason they change oil every 3-5k miles. Being bombarded with ads everywhere saying how it's good for the engine, how you must do it,  and so on. I don't know why kind of oil they have over there, but whenever i read comments about that, it's almost like people were bragging how they change even after 3k miles, and no 5, or 6k, as if they were putting some junk in there, not oil meant to last.

[Derek.w]

Looks like iradium spark plugs they can last 100,000 miles or more.

[AisinW]

Most Americans and Canadian change oil every 6 months/5k miles these days including in quicklube style stores.  These days all oil with ILSAC GF6 needs much higher quality standard than early adoption of GF2 era when started leaving 3k miles oil change interval and move ot 5k miles interval.  

People who are active in BITOG and other forums are maniac.  I think only fools still do 3k miles wastefull OCI.  10k miles interval is ok if we really use a good synthetic oil group III or IV.  In the USA, engine oil is cheaper because fuel is also cheaper, about 65% cheaper.  For instance, a basic 5W-30/ 0w-20 full synthetic oil Dexos 1 gen 2 approval (similar to Mobil 1) from Walmart brands is only $19+tax per 5 quarts. https://www.walmart.com/ip/Super-Tech-Full-Synthetic-SAE-5W-30-Motor-Oil-5-Quarts/17133942 or https://www.walmart.com/ip/Super-Tech-Full-Synthetic-SAE-0W-20-Motor-Oil-5-Quarts/254038905

But even with such oil, if we do 10k miles oil change interval/1 year, the tendency of oil consumption is higher especially with low tension piston rings engines like pre-2015 1.8L hybrid. 

[AisinW]

I just ordered 4 SC16HR11 from Autodoc. They are made in Indonesia and the internal resistance are 4.6, 4.8, 5.2, and 5.4 kOhm.  It is within 25% values.  I used Lidl Multimeter with automatic ohmic range. Cheap €3 eBay multimeter cannot read them,  >2 MOhm, out of range. 

Fake spark plugs often have internal resistance 2x or more between one to another sample.  

I am more afraid when OEM product have label made in Japan.  Almost all counterfeit always said made in Japan. In facts, only a few OEM are made in Japan: Waterpump, ECU.