r/Excursion

I just found this group. A couple of pics of my Excursion on a trip to Utah. 2000 6.8L gasser. 4x4 Limited. I’ve owned her for about 9 years now. She has been all over the country on road trips. Great truck!

Front end rapid vibration 30+ mph when hitting bump.. (not death wobble) it goes away if I hit another bump or slow down. . It feels like 5% of a death wobble

99-04 Front end has

tight track bar no play

Tight ball joints and tie rods no play

New mile marker locking hubs

Tight hub bearings no play

Front axle shafts have no sticky spots in u joints no play in u joints

New front axle shatt thrust washers

And before someone says its the steering damper its definitely not that i drove the truck for months without one

I don't have the front axle vacuum seals installed as I have manual hubs.. do the stub shafts need the seal for support ?

The superduty springs have been on for 25k miles without any issues.

So, I'm not new to wrenching, but I know where there is gaps in my knowledge and one of those is pretty much anything with the voodoo magic we humans call electrical. I know it either works or it doesn't but trying to narrow down electrical concerns has always been a shortcoming of mine. I can connect wire from here to there and know enough to not kill myself or let the smoke out (most of the time).

With that said, I acquired a new to me Ex (V10, 4wd, '03) about a month ago and took care of all of the mechanical issues, but one that has been on the back of my mind is how high the truck revs at start up cold or hot. Cold im used to, but when its hot it still revs up over 2500 and high idles for 10 or 15 seconds before settling to ~800rpm. My first thought was maybe the IAC, but it doesn't show any other symptoms of a failing valve. Then while driving I noticed that it shifts a little more firm, and at higher speeds than my 2000 v10. Additionally when coasting down a hill it seems to take quite a long time before it goes into fuel cut off than im used to in general.

Fast forward to last weekend and I installed an android head unit and finally got the torque app running. I have it connected via USB (same dongel I used for forscan). While I havent monitored it with forscan yet (need go renew the license), I noticed a few things that maybe made me point towards the TPS. First was the instantaneous mpg gauge and current fuel consumption through torque. While I know this is mostly unreliable, while coasting down hill at around 55-60 mph, the mpg gauge only goes to about 35mpg and fuel consumption shows about 1.9 gallons per hour. My assumption is that under fuel cut off coasting down a hill that the mpg should be maxing the gauge and the consumption should be all but zero.

So I look at my TPS gauge and it reads about 26.5% at idle and 94% at wot (engine off) and my short/long term fuel trims are trying to lean things out to the tune of 5-7%. While this all seems normal, under any throttle while accelerating or cruising the fuel trims are near 0 where I expect them.

The truck is hot right now and I dont have another sensor on hand unless I swap the one from my 2000 (which i might do this weekend). As far as I know the truck has no tune, but it has a k&n kit on it and previous owners have installed everything from subs to car alarms and remote starters so who knows what else they've messed with.. Do any of you think im on to something, or are these like my old SHO's where each one has its own personality and different status quos?

Sorry for the long read.