Sudden Extreme Shuddering

[Adam Roby]

Hey guys, never experienced this before and I have no clue what to look at.

I was on the highway for the past hour in very heavy rain so I didn't hear anything strange or feel anything noticeable. When I got off the highway, I noticed an extreme shuddering when decelerating. When pressing the gas to advance it's "smooth" but just letting go of the gas pedal the whole truck shakes like I'm driving on those truck warning bumps on the side of a highway. I pulled over, don't see anything (in the rain). All the wheel bolts are still there and not loose. Brakes in front were done around Christmas, rear is just about due...

Can water be doing something strange here?
Is there a list of things I could check to tell what's wrong?

I sure as hell hope its not something major, I am tapped out - can't afford a massive fix right now. I am worried it might be transmission / differential / something power-train. Any suggestions where to look would be much appreciated.

 

[ltd02]

Did it stop when you applied the brakes? If Torque converter shudder, applying the brakes should disengage the TC.

When was the ****** serviced last? Ujoint ok? Front propshaft ends OK?

 

[HoosierJeeper]

I'm guessing ujoints.

 

[Adam Roby]

Did it stop when you applied the brakes? If Torque converter shudder, applying the brakes should disengage the TC.

When was the ****** serviced last? Ujoint ok? Front propshaft ends OK?

Thanks for the replies.

****** was flushed and fluid replaced last spring.
I'll have to check the u-joints tomorrow, I'll look on here for the best way to do that. Not sure about the propshaft...

My "feeling" albeit possibly not technically sounds is that a tire/wheel problem would not show this much shudder at such a low speed. U-joints would probably also show more vibration at speed, could they really give this kind of pretty heavy shudder at very low speed? (We're talking driveway speeds, let go of brake and just drive on idle already starts to shudder). Braking also seems to make it worse rather than better, does that automatically eliminate the TC as a culprit?

 

[ltd02]

That doesn't sound like Torque converter to me. Any noises associated with the slow speed vibration? I'd lean toward U-joints but at such a slow speed seems iffy. Maybe it is time to check the rear brakes and see if the ebrakes fell apart.

 

[HoosierJeeper]

U joints could be bad at low speeds if they're really worn or broken. I once had a few caps shatter on mine and one fell off, couldn't go over 10 MPH without throwing up almost.

 

[forcefed44]

Check the front D/S CV joint. If the boot is torn and the joint is dry and water got in there.. It's going to make a hell of a vibration or noise and both.. Mine was and that was my vibration.

 

[Adam Roby]

So I just did a visual check of the vehicle.
The CV boots are all perfect, I don't see any tears or grease leaking out anywhere.
All the u-joints feel tight, and turning the tire I don't see any play and don't feel any knock. I found a small screw in one rear tire, needs to be plugged but not my current problem. I took the rear wheels off, the discs spin freely, and don't feel anything loose inside but I'd have to remove the caliper and disc to be 100% sure the parking brakes have not fallen apart. When driving there is no sound, just the dash board shuddering.

The one place I found a tear, and possible water entry point is in the front shaft leaving the transfer case. There is a seal or rubber piece that has torn.

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When I left yesterday, I hit some pretty gnarly puddles from the crazy rain storm. I felt an immediate shudder at that point but thought it was just my discs were wet. By the next stop everything was fine. Drove 1 hour at highway speeds, again in some pretty heavy downpour, and when I got to the first stop that's when this shudder started again, and is still present. Something is either wet, damaged, missing... driving me crazy, I was hoping it would just out at me.

 

[Logan Savage]

If I'm not mistaken you can remove the front shaft & still drive the jeep leaving the lever in 2WD . That torn boot on the front shaft may have caused that joint to go bad causing your problem . Worth a try to see if your shuddering goes away with the front shaft removed .

 

[Adam Roby]

That could be a relatively quick test to make sure, question is can I safely drive without the axle in place, or do I risk getting more dirt/water inside the TC? I could maybe make a temporary cover plate I suppose.

 

[Logan Savage]

The yokes remain in the transfer case & front differential so you wouldn't have a problem with anything entering or leaking . We are talking about the front driveshaft , not an axle .

 

[Adam Roby]

My bad... typo, I meant the drive shaft not the axle, sorry for the confusion.

Indeed it does seem to be a bad U-Joint. Swapping it out now.

 

[Adam Roby]

I swapped both rear u-joints, the shaking is gone but I do hear some noise now from the front when turning. I think I need to replace the front drive shaft or rebuild it. RockAuto only shows a complete front driveshaft for around $500. EBay shows joint repair kits for $30+... can it really be rebuilt or do you need a completely new shaft?

 

[ltd02]

Easy rebuild. I like the stuff from these guys: Jeep Front Driveshaft CV Joint

 

[HoosierJeeper]

If it's while turning I don't think it'd be the front driveshaft. Probably a CV shaft.

 

[Adam Roby]

Got a point there... the boot is torn on the front shaft anyway so it can't hurt to replace the entire end. Have to test the CV...

Are all these joints supposed to be replaced as part of some scheduled maintenance or are they just "replace when broken" type parts?

 

[HoosierJeeper]

Replace when broken

 

[jharrisliberty]

Easy rebuild. I like the stuff from these guys: Jeep Front Driveshaft CV Joint

Wish I would have know about this before shelling out $100 for mine. But at least I will know for next time.

 

[Adam Roby]

I called the local autoparts, they don't sell rebuilt kits, only the full drive shaft and they want a whopping $750 for one! What the hell... how come I can get a $30 rebuild kit but they only sell a $750 new shaft? Don't make any sense...

In that link, it says front drive shaft CV joint. Just want to make sure that is on the transfer case end. What is the other side that goes to the diff, it is also a CV?
Also, are the side CV shafts also rebuildable?

 

[ltd02]

In that link, it says front drive shaft CV joint. Just want to make sure that is on the transfer case end. What is the other side that goes to the diff, it is also a CV?

This is the kit for the other (diff) end of the front shaft: Jeep front Driveshaft CV Joint - Diff side

Years ago I bought an intact (assembled) diff end from them for the same price. Guess they don't sell that anymore. Still sitting on the KJ shelf in the garage.

Also, are the side CV shafts also rebuildable?

No I found out recently you can only get a boot kit not a complete rebuild kit.