- #40 of 43
-
Re: Quest for better MPG [harborharley]
by buffalojoe
-
Jul 13, 2009 (2:14 pm)
-
|
|
Replying to: harborharley (Jul 13, 2009 7:57 am)
Yeah, I had a look under the hood and I groaned when I saw what was there. Did the replacement of the plugs help your mileage? I'm still trying to figure out if I want to try it or take the smart way out.
As far as tires, I hate Goodyears in general and am glad I'm not the only one.
Thanks! 
|
- #41 of 43
-
Re: Quest for better MPG [buffalojoe]
by harborharley
-
Jul 14, 2009 (5:52 am)
-
|
|
Replying to: buffalojoe (Jul 13, 2009 2:14 pm)
The manual says to replace plugs at 100,000 miles. When I measured the old plugs the gap was almost 1/8", pretty big and plugs were worn to some degree. I would say the engine runs better, smother with the new plugs, idles just great. You can do the plug job but take your time. If plugs have never been replaced and you are at the 100K mark do it. Also you may damage wires so consider replacing them at the same time. The plug wire boots are quite long and were difficult to remove without damaging them. If not up to the job, let the dealer do it. I did the job over a two day period to ease my back from bending over those fenders!
The Generals HTS seem to be quiet, smooth riding and handle well. I do mostly street, hi-way driving. Check the Tire Rack site for reviews on them. These tires were so new when I got them, my garage smelled like fresh rubber for 2 months! I think i paid $550 for 4 balanced and installed at Tire Rack here in South Bend, IN.
Let me know how you did on the plugs.
|
- #42 of 43
-
Re: Quest for better MPG [harborharley]
by buffalojoe
-
Jul 23, 2009 (9:35 am)
-
|
|
Replying to: harborharley (Jul 14, 2009 5:52 am)
I finished the plugs over the weekend and it took me a total of 7 hours (2 hours one night after work and 5 more in a straight shot on Saturday). I don't have the angled socket extenders so I was splayed out over the engine with the ones nearest the firewall. What a pain. The interesting part is three of them had corrosion on the higher part of the threads and the nut. I'd never seen that before on any of my vehicles. I have the 5.4L with coils but none of the rubber looked damaged enough to leak. I don't see any white smoke so the head gasket must be okay. It's a bit weird, though.
The plugs looked as if they were wearing normally. There wasn't any fouling or anything that appeared out of the ordinary. We'll see if this helps the mpg.
|
- #43 of 43
-
Re: Quest for better MPG [buffalojoe]
by harborharley
-
Jul 23, 2009 (6:00 pm)
-
|
|
Replying to: buffalojoe (Jul 23, 2009 9:35 am)
Ok on doing it yourself. I may have taken 5 hours total, I forget now. How was the plug on the passenger side rear? There have been some problems with the threads on the head on some 4.6 engines. This plug has actually blown out of the head in some cases. I did squirt some WD40 in the plug holes before I tried to remove them. I think I let it sit over night and soak in. Anyway good deal, you saved some money doing it.
As I mentioned with 90K miles on mine the plug gaps were way out of spec, much opened. I have a 99 Expedition and it's almost show room condition! I get around 17 to 18 mpg on the hiway conservative driving.
|
![[F]](http://a332.g.akamai.net/f/332/936/12h/www.edmunds.com/media/townhall/webxicons/site.gif){kind=small}
Forums
SUVs 
