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Nov 18, 2015 | 09:49 AM

DonsF100

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Hi all, I recently bought a 1997 Eddie Baur Expedition. Right off the bat I knew it needed a little TLC on the front suspension. Replaced both lower ball joints and the pitman arm. Upper ball joints, all tie rods and idler arm all exhibit no play. Then I had the tires balanced. Still have a vibration at speeds above 60-65. But it's not all the time. Sometimes it rides nice and smooth, but then it will start vibrating after coming out of a bend, or hitting a bump.
Is there something else in the drive line I'm missing? Maybe I should've watched the kid on the balancer?
It does need shocks too, but I wouldn't think weak shocks would be the cause of the vibration. Or could it?

Nov 18, 2015 | 09:54 AM

alloro

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What you've described is typical for worn driveshaft u-joints.

Nov 18, 2015 | 10:00 AM

DonsF100

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Aha. Now, are you talking about the main front to rear driveshaft or one of the shafts coming out of the transfer case to the front wheels? (Man, I'd hate to have to take all that apart again).

Nov 18, 2015 | 10:16 AM

DonsF100

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Well, I just went out and put it in neutral and crawled around shaking and turning both ends of the drive shaft and both front wheel shafts. No play at all.

Nov 18, 2015 | 11:10 AM

alloro

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Since you have a 97 you have the 2WD option on the selector switch. As long as you're in 2WD the front shaft does not turn. That would leave the rear driveshaft as the likely culprit. Getting under and twisting/moving the driveshaft is not a tell all.

Nov 18, 2015 | 08:44 PM

pdqford

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Quote:

Originally Posted by DonsF100

Sometimes it rides nice and smooth, but then it will start vibrating after coming out of a bend, or hitting a bump.
Is there something else in the drive line I'm missing?

I'm not saying this is your solution, but just went through this on a 2000 Expy. After replacing two u-joints, no help. Pulled the rear rotors and bingo! One of the ebrakes had lost its hardware to rust. One shoe lost its lining and the other shoe was getting ground up in there. Prolly getting jambed into the rotor hat and releasing, on/off/on/off causing the vibration. Put new ebrakes/hardware/rotors on and all was good.

Like I said, may not be your issue, but when you posted it happens when you hit a bump, it might be worth pulling the rear rotors for a look see.