Replace spark plugs?

My truck has 75,000 miles on it. I went to replace the plugs yesterday because I figure its probably past due. I went to pull the first plug and it looked really good/clean. What do you all think? Should I go ahead and change them, or just leave them?

 

I'm in the same boat as you, 70K+ miles and my plugs look good, but should I just replace/upgrade anyways. Looking forward to seeing what comes of this thread. I was thinking plugs and wires. Congrats on only 75K on an 03, sadly my 07 has already reaches this point as well. The fiancées new car get great gas mileage so I'm hopping my pickup can be just an around town truck from here on out.

 

In the 3.4 they need to be changed every 30k. Not sure on the 4cyl. Gap should .040 to.043

 

I just did my plugs a few weeks ago, along with most of the 60,000 mile maintenance. also an 03 v6 , has 58,000 on it. get this though.... I bought the truck in 2008 and hardly drove it, pretty much changed the oil and did minor maintenance when i got it and then put minimal miles on it. ended up selling my 89 pickup so i started driving the 03 more and figured it was time to do some maintnance befor putting too many of my own miles on it. When i pulled the plugs, the ones on the bank under the intake side were much more worn than the others (not to mention a different brand) which leads me to believe the previous owner/ mechanic/ whoever, got lazy and only did 3 plugs and didnt want to take the intake hardware off to get to the plugs. Have you owned the truck since new? because those plugs look to be in pretty good shape for 75,000. if your not sure i would say pull them. but if they all look like that one, they have a lot of life left probably

 

I can tell you that i bought my 98 tacoma in August 09 and i replaced the stock plugs and wires at 169k!!! It ran better after i replaced them, but the plugs looked about like the one you show above, I obviously wouldnt have gone this long without changing them, nor would i recomend it but the fact that the truck still ran good was a statement in of itself, as for your plugs they still look good to me, but it never hurts to change them

 

In the 3.4 when changing them what plugs would you recommend? Also the truck will be S/C soon.

 

From the factory, I do know that the tacomas came with different spark plugs on each side of the block so that explains the different spark plugs you found. I have owned the truck for about a year, but did talk to the previous owner who owned it since new and he had never changed the plugs before.

 

Is replacing the wires a fairly straight forward job?

 

pretty sure the 3.4L uses coil packs, so no wires

honestly haven't spent much time under my hood other than to do an oil change and air filter lol

 

There is only coil packs on the pass side

 

Cost of new spark plugs - under $20
You obviously know how to change them.

So.......... just change them.

 

If its gonna be sc'd soon.......may wanna go with iridiums. They may be better for forced induction.

Also.........coil packs on pass side fire the plugs on the driver side.

 

Definitely a good way to look at it, thats my theory on oil changes, spend a little to get a lot.... not that letting your plugs go will exactly ruin anything. And good call on the factory using 2 different kinds of plugs, i didnt think of that, i just figured someone was getting lazy. I tell you though, those plugs look super clean compared to what came out of mine at 58 k, not clean in an oil fouled sense but mine were very worn.

 

Going through the work to inspect them just as well replace em. I think I have coil packs on both banks. Put some anti seize on the threads before you re-install, a little die electric grease on the boots to.

 

I'll have to look and see but I think I got iridiums with the URD kit. So with the coil packs your saying change them too? What about wires?

Edit: just read there is only coil packs.

 

All 3.4 motors only have three coils on pass side no matter what unless you put in a vortex v-8 from chevy. I run only NGK iridium plugs only, not the pos stock two pronged junk that cannot be gapped whatsoever from the factory, the best Toyota builders in the world also run NGK iridium plugs in their race machines, they get three times the life out of them and the gap doesn't warp out on it's own+the people that put em in will notice a considerably quicker start up time than stock. They can cost about 50.00 bucks but they pay for themselves. Good luck...

 

Considering I only pulled one plug to inspect, and it was the NGK, makes me wonder what the Densos on driver side look like.

I think I'll go ahead and pull them and replace them this weekend just to be done with it.

 

not true, you still have to buy wires but only a set of three because each coil pack serves for two cylinders, instead of having a distributor that runs spark on every individual plug.

 

good call on that. anyone have any good input on why the factory would use 2 different plugs, just curious?

 

only coil packs on the passenger side.....driver side has wires.

thats just how they come down the assy line at Toyota.