jim.peter

Got a 2004 off road ranger, 60,000 miles. Its got a vibration which starts about 55 mph. It drumbs the cab making it hard to hear the radio. Its a high speed vibration. Hanging on to the steering wheel feels like hanging on to the handle bars of a cheap motorcycle. Smooth as glass up to 55mph. Got new tires too. A friend said it felt like it was in 4 wheel drive.

Is the front drive shaft supposed to turn when it's not in 4 wheel drive? It turns. I had an earlier model with automatic hubs that would release the front drive system in 2 wheel drive. Not sure about this one. The rear drive system looks like new.

Rangerak

If you don't have manual locking hubs your front drive line will turn with the wheels while rolling down the road, they just won't have any power to them if the transfer case is not engaged. Best way to describe it would be the front end would be "coasting." A clue to your vibration could be that the rear wheel drive system "looks like new." Does it look as dirty as the front system from normal use? If not, and looks new, some work mostly likely was done on it. Automatic or manual transmission? Does it have a driveline support bearing between the transmission and the rear end? Sometimes they will go out on you and start to vibrate. If work was done and the driveline was taken out it could be out of time, also called out of balance. I have read about other guys having the same type of vibration and they took out the rear driveline and greased the slipjoint real good and put it back together and the vibration stopped.
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jim.peter

Got no locking hubs. Got no center carrier in the drive line. I have a nice clean looking underneath because I don't often get off the pavement. This is the wife's truck. She owned it since new but I never drove it. Through a recent change in circumstance I'm now the primary driver. Hell, for all I know its been shake'n since new.

I like the "grease the spline" idea. It feels like it could be something like that.

It's smooth as glass up to 54mph. Starts drumming the cab at 55. Drives you nuts at 60mph. Sorta lets up around 73 or so.

Help.

pete

as you shift into 4-wheel drive, there is an electric acuator that engages the front axle to run in 4-wheel drive mode (to lock it in). when in 2-wheel drive, the front axle should not be turning, (also front drive shaft should not be rotating ) thus - automatic locking hubs.

pete

check the wiring to the solinoid that locks the front axle, the axle may be locked in, engaging the front axle, while not in 4X4.

jim.peter

Well, the front drive shaft is turning when going down the road, in 2wd. I guess whatever disengages the axels is a good place to start looking. Seems the few mechanics to which I've talked have mixed opinions about whether or not the front axels, on that model, actually are supposed to disconnect. Gotta get that verfied.

Rangerak

Engaging and disengaging happens in the transfer case. Unless you have to get out of the truck and lock the hub manually by spinning the knob you have a basic hub and bearing assembly. Hub sits on the splined end of the front axle supported by the wheel bearings. The axle goes directly into the front differential. No locking or unlocking automatically happens in the hubs or the differential, they are always locked direct drive. Everything turns when going down the road 4WD engaged or not. Have you changed the oil in your transfer case? It uses ATF. My Haynes manual says to change the t-case oil every 30k and to lubricate both the front and rear slip yokes at 30k also. To get a good look at the front hub assembly most online parts suppliers have a picture along with the parts description (cuz I can't figure out how to post a pic in this note). I am not used to seeing clean anything under a truck around here because of most of us live out in the woods somewhere or the sand and salt on the highway takes a toll on the undercarriage as well.

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Rangerak

I put a picture of the the hub in my photo album in my profile if you would like to see what one looks like.
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jim.peter

That's the way I see it. I talked to a Ford dealer service manager yesterday and he said otherwise. I think rangerak is right though and the dealer guy is wrong. I can't find any wires or vacuum lines going to any front drive part to cause any switching to take place. I think its all done in the transfer case.

Anyway, I had the tranny and t/c oil changed recently at a dealers garage. I'm not too sure about the splines getting greased though. Gotta check into that. The buzz feels a bit like a bad u-joint but they're so quite when turned by hand and feel really smooth too, not creaking like you'd expect.

pete

I should have done my homework-2001 and newer have a live axle (always engaged )