Spark Plugs & More
 

My 04 GT is creeping up on 100,000KM and I was wondering if I should change the plugs...

If So...

Should I stick with Ford Plugs or go with another brand?

Some say you should always stick with your factory brand plugs
And of course
Others swear by aftermarket plugs

Also, is there any other maintenace that should be done at 100,000?

wouldn't hurt to do your fuel filter and air filter if you don't have an aftermarket one. As for plugs, from what I hear stick with the Motorcraft factory plugs. I used champions when I did mine, and havent had any issues at all. Can't go wrong with factory though.

Only use Ford Motorcraft,............. most other plugs,.... especially crappy tire are garbage.

OK so Motorcraft Plugs...Change the fuel filter...Air filter is fine as I have an intake
What about transmission work (fluid, filter?)
What about my coolant?

^^Is your car a standard or an Auto? If it;s an auto, wont hurt to change the tranny fluid, manual should be OK I would think. Diff fluid change wouldn't hurt either. Just did mine last year.

Stock plugs are good,you will get some longtivity out of them when sticking with them.Or if you want to go with copper plugs,AutoLite 764's are also recommened for our 4.6L for the best performance,but they will be needed to be changed more frequently.

I will change the fuel filter (ford), plugs (ford) and coolant (prestone)
I am going to leave the diff fluid till I get my new gears
When I change the coolant I guess I should flush it as well right?
With something like Prestone SUPER FLUSH as the coolant that is in the car might be original as I am the second owner and the car is 5 years old

Stay with Motorcrafts, these are great plugs...just make sure you gap them to your specs.

If you're running original plugs at 100,000km's I'd say change them. From my experience (I know its not a Mustang) but I had a 00' F150 4.2 V6 that had 120,000km's on it before the plugs were changed and what a difference new plugs made in fuel economy. I also did fuel and air filter and that also helped a lot so I'd recommend those as well.

Honestly, my '96 has 80 000k and i did my fluids and filters

I did the stupid thing of paying just over 100$ for botch platnium 4s and they were the biggest waist of cash!! with about 300kms on them and they started to fall apart already and made my car run like crap. I then put in ngk g power tr55gp. They were fairly cheap so if they didnt work good id just go back stock but theyre doing good and i noticed a slight slight gain in power especially over 3gs.