2014 4.0L spark plug question

just replaced the plugs on my 2014 tacoma 4.0L replaced with all Denso plugs question is why did the factory put NGK on drivers side and Denso on passenger side ??

 

It is apparently something to do with a contract Toyota has with both companies. No mechanical reason - just fulfilling an agreement.

 

LOL figures .... plugs went well but center plug tube seal is leaking so have to pull the cover and replace the tube seals, lucky it's only the passenger side

 

Welcome to TW! Was the truck purchased new? How many miles? Finding both types of plugs is typical and often discussed but it is generally an indication the plugs have not been changed as typically when changed all of one type are used. There is a whole thread out there with info regarding the spark plugs as well as a how to, which you obviously do not need. Searching with your search words on your favorite search engine and adding "Tacoma World" to the terms usually produces better results than using the search function within the forum.

 

2014 bought new has 80k on it and changed them just thought it was strange i had read it could be that way, i did search but guess i didn't put the right words in

 

Here is an example of the results I found:



I usually click on the "More results from www.tacomaworld.com" link and start exploring from there.....

 

I am going to do the plugs in my sister's V6 2011 Camry soon. I'm curious to see if it also has a mix of Denso and NSK.

The engine is sideways in the Camry. The front 3 Camry plugs practically change themselves they're so easy. The back 3 plugs look like a freaking nightmare. Gonna have to take the windshield wipers and complete air intake off, including the throttle body. Ugh!! Tacoma set up is WAY better.

 

biggest pain was getting the coil pack plugs off a couple but all in all easy job

 

There are as many opinions as to why Toyota went half & half on 2nd Gen V6 spark plugs as there are answers as to what happened at Area 51 in 1947.

If I'm not mistaken, part of the emissions warranty extends to 80,000 miles. Many of the long-life plugs used in some Toyota engines calls for a change out at about 120,000 miles. That's well past the 80K emissions warranty. I may stand corrected, but these engines with 120K plug swap specs have a single brand of plug on each side. When I changed plugs on my '06 Avalon(6 cyl), there were only Denso plugs in the engine. The '06 Avalon's 2GR-FE engine has a 120K plug swap specified in the services guide.

But...the 1GR-FE V6 2nd Gen Tacoma engine (for the most part) has copper spark plugs that call for replacement at 30,000 miles. That's well before the 80K emissions warranty is up. The warranty guide clearly states that a plug change at 30K is required in order to satisfy the emissions warranty.

So...a 1GR-FE V6 2nd Gen owner pulls into a Toyota Dealership with an emissions issue. Toyota could be on the hook for a pricey repair...new CAT maybe? Let's say the truck has 60,000 miles on it. The dealer tech pulls the plugs and sees a set up Denso in one bank and NGK in the other. The dealership knows the original plugs were never changed. The 30K plug change requirement has been violated. The owner is now on the hook for the emissions repair.

If Toyota wanted to use half of this brand of plug and half of another in order to spread the wealth, they would have done so across the board with all of their engines and not just the 1GR-FE used in 2nd Gen Tacoma's, but further down, you will see that Toyota will own 49% of Denso in April 2020 and owns no part of NGK.


How much of Denso does Toyota own?

Denso, a Toyota Group supplier, will own 51% of the new company, with Toyota holding the remainder, the companies said in a joint statement. They said they aim to establish the company in April 2020 with a capitalization of 50 million yen ($458,968) and about 500 employees. Jul 10, 2019

Who owns NGK plugs?

United States. Established in 1966 - NGK Spark Plugs (USA), Inc. was founded as a subsidiary of NGK Spark Plug Co, Ltd., of Japan.