Hello fellas,

Just did a 3k mile trip from Seattle to Austin TX, eastern Oregon close to Rouge River, Western Colorado from Grand Mesa/Junction n hey 550 South via San Juan Mountains, loved it.
Anyhow a few hours into the trip we noticed shaking at idle but only when I let the brake pedal go or just before coming to a stop. Lately it would shake around 45MPH.

I took off the coil pack and the rubber boot has a crack, the inside looks fine, the dealership quoted $140 for one, also should I take the plug off? The 8th one was a ***** to take out, took some PB blaster soaking and slowly FF-RR turning to come off, I did not check the gaps, the plugs are Desno SRK exact match, and I do use dielectric grease and a bit of antiseize, and basically had replaced them 2 weeks before the trip, the V8 now has 270k.

What option would be best

1. Being super cheap here, has anyone repaired the rubber boot with Silicon type adhesive or another method?
2. Have tried 3rd party and have been happy with them?
3. I should suckup and order OEM online, a quick glance tells me app. $75ish?

Regards

I replaced all 8 coilpacks on my V8 a few months ago. Get Denso or OEM (OEM is made by Denso), nothing else. Mine is a 2003 and I don't recall there being a rubber boot on the coils.

I got all 8 coils from rockauto.com and bought Denso coils. Aftermarket coils tend to cause issues down the road and I would avoid them personally. My OEM coils had 328k miles on them and all had cracks, which is why I replaced them.

You can get the boots separately. I remember seeing them for my 5.7L. Search for Coil On Plug Boots. Although I don't know if that will fix your problem with the shaking.

The 5.7L and 4.7L V8 aren't even close to being the same, other than having 8 cylinders.

Yes, they can. Rockauto has both NGK (available individually for $5.60 each) or Denso (set of 8 for $50.48) boots for an '05 T4R 4.7L V8. Not sure what year you have. Either of those would be good. If it were me, I would replace all of them....

Good call. I just looked on rockauto and see the boots being referenced here. Yeah, those are replaceable, you are correct.

However, to the OP, if you are seeing cracks on the coil body that extends down to that boot, which could also look like a casting line from the manufacturing process, the whole coil should be replaced and not just the little boot on the end. That extension is where I saw the cracks on my OEM coils and why I replaced all 8.

Sorry for the late update, but I did replace the boot with $5 NGK, and that took care of the problem. Although being baked but enjoying at Dave Crockett National Forest in Texas;), she been great in the backroads