tell me your opinion on spark plugs

[dashhho]

My '05 B4000 4.0L doesn't start up very easy and I figure my mileage is lower than it is supposed to be.

I pulled out a plug and the previous owner ran NGK TR551GP which look to be single platinum. The ground strap looks to be slightly burnt away so the gaps grown. I'm guessing this is my issue? Some motorcraft plugs are on their way.

 

[Dirtman]

Spark plugs is goes zzzzzap!

NGK plugs don't belong anywhere near a Ford engine. Motorcraft or Autolites only and if you have a DIS system (like you do) you should always run DOUBLE platinum or iridium.

Whether the worn plugs are the problem is impossible to say, but old worn plugs definitely wouldn't be helping the situation so replacing them is smart anyway.

 

[sgtsandman]

Look at your plug wires as well. If they look like the ones that came with the truck in 2005, it’s time to change them. Don’t go cheap or you could have problems with the wires even if the plugs are fine. Like the plugs, I would get motorcraft wires and make sure the light colored ones go to the back cylinders. They are like that so they are easier to see. And more than likely, you will need to go through the wheel well on the passenger side to get good access to the plugs and wires. The box for the A/C will be in the way otherwise.

 

[19Walt93]

I prefer Motorcraft to anything else, Autolites used to be the same but that's no longer true.

 

[Eddo Rogue]

Mine hated NGK, ran like crap. Didnt like the Bosch either. Now I run autolite double platinum and love them. Motorcraft is also good.

 

[dashhho]

Now a second question. What gap do yall use?

Looks like Ford specs 0.054"
The Motorcraft ones I bought seem to all be around 0.064". Should I gap em down to 0.054"?

 

[Dirtman]

Double platinum should come gapped. If not DO NOT USE A TYPICAL GAPPING TOOL! (Coin type) You will break the tiny platinum plate off the ground prong, you must use a gap tool that grabs the back of the ground and not stick anything actually between the electrode and ground. I believe gap is .051-.054.

It's easy to reduce gap by very very gently tapping the ground against something solid and checking with a feeler gauge.

Again never pry on or jam anything into the gap!

 

[cbxer55]

Motorcraft double platinum in my 98 Ranger and 07 Mustang. NGK TR-6 in my Lightning.

 

[Eddo Rogue]

Factory pre gap

 

[sgtsandman]

They come pre-gapped from the factory but during shipping and handling, they could have dropped and knocked out of proper gap. Even pre-gapped should always be verified before you install them.

 

[dashhho]

Well I got all the plugs in.

When I went to push the boot on the last plug the wire slid up inside the boot...Guess I'm paying the price for being cheap on my wires. Is there any easy way to pull the wire back down? I could try to shove some needle nose pliers in there. I also thought I could crimp the wire so it's tighter and hopefully it pulls the wire back down the boot when I click the plug in place.

Right now when I click the wire on it pops off as the boot is putting pressure on the plug.

 

[Eddo Rogue]

Well I got all the plugs in.

When I went to push the boot on the last plug the wire slid up inside the boot...Guess I'm paying the price for being cheap on my wires. Is there any easy way to pull the wire back down? I could try to shove some needle nose pliers in there. I also thought I could crimp the wire so it's tighter and hopefully it pulls the wire back down the boot when I click the plug in place.

Right now when I click the wire on it pops off as the boot is putting pressure on the plug.

I got a pair of oversize locking forceps that come in handy for stuff like this. I would get new wires.

 

[Broosedamoose]

If you bought cheap wires you will find yourself replacing them soon. Break down and get a set of Motorcraft or Taylor wires. You will thank yourself later.

 

[blbzeckhart]

I have a 94 Ranger with the 4.0L in it. I am a parts guy and I know the business. The spark plugs in my Ranger originaly are not the same as what came in the truck from Ford. With that said, the upgraded plug from Ford is an Iridium and they are not really expensive. I get a heavy discount but the price for the OE Plug from Ford is not expensive, put them in your Truck. Ive worked in A/M and OE and I would def put the OE plug in your truck. I have seen an enormous improvement in performance with the new OE Ford plugs. Jusy sayin

 

[ekrampitzjr]

I'll be a little different here. My 2011 4.0 Ranger is running Denso TT platinum-iridium plugs now after changing the original Motorcraft plugs at 102,000 miles. The wires were changed at the same time with new Motorcraft. The truck runs great on Densos. Really.

My mechanic buddy who changed the plugs (long story, I couldn't budge one of them) talked me out of using Autolite. He said he had seen too many problems with that brand in different vehicles. Some other forums say that certain Autolite and Motorcraft plugs have a pressed-together two-piece outer metal shell that likes to separate during removal. This leaves part of the plug in the head. It's common enough that a special tool is available to get the separated part out of the head.

He saved the old plugs for me and pointed out a blue dot painted on each one. That was the original Ford assembly mark, he said, showing these were the originals the truck was built with.

I saw plenty of comments elsewhere about not using NGK in these engines. Densos had great reviews.

The original plugs were supposed to be gapped 0.052–0.054". After 102K miles they were all eroded to about 0.070". I gapped the Denso plugs to 0.052".

The 4.0 SOHC engine is not known for great fuel economy and the EPA highway rating is only 20 mpg highway, but I regularly see 21–23 mpg highway with these plugs and synthetic oil. So there are alternatives.