So I'm used to the vibration coasting down from 110-115mph or so, I would mitigate it by applying light throttle. Recently it started coasting in the 75-80 range, then 70-80, and now it does it just plain cruising in that range as well. Nothing below 65, and nothing above 80 (coasting, cruising, or under load).

It's definitely a mechanical vibration, tires are fine, wheels are fine, wheel bearings are new... Thinking driveline u-joints? Don't have the money to throw parts at it unless they're the fix. I've consulted Christina's analysis chart and this is the only thing that makes sense so far.

No other symptoms anywhere else except those ranges. U-joints are, as far as I know, OEM originals. 276k miles seems like a hell of a life for them, especially with the abuse they've seen in the past 75,000.

Thoughts, advice, and so forth?

I need to crawl under and give things a shake and wiggle, current condition is unknown. Left for a road trip to meet the wife's ex so he can have his time with his son, and the X was so bad at the aforementioned speeds that we turned around and swapped vehicles. It was worse this morning than it's ever been and I wasn't risking catastrophic failure with a zero emergency fund.

 

I had a really bad vibration as well on my drive back from Tx to Colorado. Turned out the drive shaft was out of whack. Got it rebalanced and put on some new u-joints..now it is smoother than ever. Mine was the worse in the 50-60MPH range at 75-90 no vibrations and once I dropped below 45/50MPH it was gone.

 

If you feel that it is the u joints, do you have any idea what kind you'll go with?

 

I would get the U shaped ones, but that's just me.

 

I get the same vibrations passing through 110 and going back down to about 80. These rigs were not designed for that so I figured it was the truck's way of telling to chill.

 

Figuring on the Spicer non-greaseable (5-1410x IIRC) for the strength and reliability factor. It doesn't go off-road anymore, just a pavement pounder these days with part time sleeper duty.

It didn't vibrate all the time, the 100+ started happening months and months ago, then the 75-80 and a few weeks ago it started doing it 70-80 no matter what, and I haven't been over 90 since it worsened. Don't need whatever component it is failing at triple digits in 9000 pounds.

 

Had similar issue, but mine was at low speeds with light brake pressure to stop. U-joints, I used the spicers, only ever topped out at 85 with her but no vibes anymore

 

As discussed yesterday my first inclination was U-joint(s), can you get underneath and apply some pressure/wiggle the driveline in any direction?

 

I'm home now, so yes I can crawl under the pig and give things a nice little "where's my money" shake.

 

You really are "Krazee" to drive the Ex so fast. I don't feel comfortable going over 80. I'm surprised wifey let's you with her in it.

 

Speeds over 85-90 are rarely achieved with wife in the vehicle, let alone the kids. Typically out in west Texas where it's 80 and 85mph, or when passing that semi that's been passing another semi for the last 9.2 miles. It's also Houston, everybody runs down I-45 and I-10 at 80, even though it's posted 60 and 65.

Unsuspecting friends? Yes. Doubting acquaintances that don't believe the performance claims, absolutely. Did I take my parents out and had my 62 year old mother threaten to spank my 31 year old butt? Oh yeah.

 

And you take a picture while doing it???

 

Actually it's a screencap from a video Razzi took riding with me. Sheesh, I may be Krazee but I'm not an idiot.

 

Back in the 90s I run my large car kenworth w900l with a 400 cat at 400 hp snapped together with 13 speed and 3.55 rears, at full pedal to the medal 85 mph east bound I-10 out in the pecos. The speedo didn't show anything more than 85.

Them there I-10 texas cow pokers run up on my left lane *** with black as coal smoke comin out them exhaust. They had to have even larger cars than me to whip by and shake my large car like in a tornado.

I wouldn't run my 02 limited over 75 cause I don't want repairs. Anyway, I just drive it lovingly and slow so everybody can jaw drop when I breeze by.

So ya, good story.

 

ATF

Stewart