2000 Ford Explorer shuddering/vibration

**FriboRage** · 01-04-2015

So it's been awhile since I've been around, I'm in a lull one irking on my comp g and I'm trying to keep it garaged for the winter so it sees as little salt as possible.

My old 95 explorer was rusting away, so I invested in a newer, great condition 2000 4wd explorer as a winter vehicle. It's almost rust free and the underbody is beautiful, interior is nearly pristine.

Ive had it a few months now, and about a week ago it developed this shudder/vibration. It only appears around 25-30mph, and slowly intensifies from there, but only under acceleration.

Say I'm speeding up to get on the interstate, it vibrates and shudders like I'm driving on the rumble strips on the shoulder, at 60mph it's pretty heavy with my foot on the gas, but then I take my foot off the pedal, so now I'm just coasting, no pedal, at 60 and it instantly goes smooth as butter. Put my foot back into the throttle and the vibration comes right back. So it's not tied to speed but load.

3 people told me to get the tires balanced, but I think that's stupid cause it would vibrate all the time, not just under throttle. I was thinking about a u-joint. I'm not that familiar with rwd and 4wd systems cause 95% of my experience is in my gp.

opinions?

**Scottydoggs** · 01-04-2015

sounds like a U joint, or a cv joint gone bad to me.

to check the u joints you can get under it trans in N then turn the drive shaft back and fourth by the rear watching for play in the u joint, as well as the by the t case. same for the front drive shaft.

you can also put the truck in low gear, get it up to say 25 mph then let of the gas and back on the gas, if the u joints are bad you'll hear and feel a good clunk.

**timboku** · 01-04-2015

U joint or sure. Had same issue on my 01 explorer. Go under car and grab drive shaft. Shake it and you should be able to see.the.pay in it.

**Fivefingerdeathpunch** · 01-04-2015

To me it sounds broke, you should fix it.

**FriboRage** · 01-06-2015

Any secrets to disconnecting this drive shaft? I've got all 4 bolts out that hold the yoke to the rear diff... I have it all sprayed up and I've been hammering on the edges for almost an hour... doesnt wanna break loose. I wanna drop it down so I can work on the u joints on the bench.

Starting to wonder if it's really just rusted on, or if there's something I missed to bust it loose.

**Scottydoggs** · 01-06-2015

so the end caps are stuck in the yolk? if so put a screw driver under the U joint between the yolk and U joint, and pry it out, you cant hurt anything.

if the front side is a spline shaft have a pan under it when you pull the shaft out, it may leak trans fluid out the back of the t case.

**Slick2500** · 01-06-2015

BFH?

**Scottydoggs** · 01-06-2015

nahhhh, you dont want to dent it, its balanced.

**Fivefingerdeathpunch** · 01-06-2015

I use a big pry bar to pop the u-joint out of the rear yoke.

**Scottydoggs** · 01-06-2015

a install tip for ya, tape the two free end caps on when your pounding the caps in the shaft. nothing worse then one of them needle bearings coming out if the cap falls off and pops em free.

make sure the needles in the two caps you need to remove are in place as the u joint is put back into them. a press makes this a easy job, the pound em in method kinda blows some times. dont pound/press them in to deep either or the cap will crack. copy how they are now.

**FriboRage** · 01-07-2015

They're not held in with straps, they're pressed in both sides.

The u joint is pressed into here

Which is the bolted onto here:

Which goes into the rear to form this assembly:

The problem I was having was, after the 12pt bolts you see in the 3rd pic were out, getting part A separated from part B.. but yeah it was just rust cause I took a crowbar to it and it popped off with some force.

Took the whole shaft down, popped the clips out, pressed the joint out of both the yoke and the shaft, pressed the new ones in on both ends, replaced clips.. all done...

Then I sheared off one of the grease fittings in one of the joints cause I went a little crazy tightening them in

Oh well, at least the hard part is over. I called it a night, but if I cant spin the remains out tomorrow I'll just grab another one for $15 I guess. The advice for the straps will come in handy for the front though... the front drive shaft u joints are held in that way... so I'll keep that in mind. Thanks for all the help.