Drive Shaft U Joints (1 Viewer)
- Thread starter Adventure Teq
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Yes sir. Took shafts off and inspected u-joints...no play, but not 100% smooth. I have heard of worse . Removed one at a time and still had some vibs.
Tires have been balanced. I feel it in the driveline. Steering wheel does not shake, just the frame, bumper, and T-case lever
Interesting that most prominent at 35 mph and 70mph. Seems there is a harmonic. I dare test it at 105mph!
My hunch is still u-joints. Going to replace them when able. Going with OEM. No reason balance is out ...no damage
Tires have been balanced. I feel it in the driveline. Steering wheel does not shake, just the frame, bumper, and T-case lever
Interesting that most prominent at 35 mph and 70mph. Seems there is a harmonic. I dare test it at 105mph!
My hunch is still u-joints. Going to replace them when able. Going with OEM. No reason balance is out ...no damage
I know!!!!!!! Shaft are like $400 for rear and something close to that on front....maybe work some over time or wait for my next check from the govt!! Lol
Quick status.
- Removed rear shaft and drove. Still vibs. Pinion flanges are within 0.4 degrees. U-joints are tight, but not 100% free moving over complete range. Very minor play in slip joint.
- removed front shaft and drove. Still vibs. Ujoints are not loose and have free range of motion. Pinion and t- case flanges out by 4 degrees! How is that? I have the slee diff drop up front. That should keep factory pinion angles. Need to look at diff mounts to make sure nothing funny. They are tight.
- next step...maybe. remove the hub flanges that lock the front axles to the wheels and drive it on highway to see if vibs are related to the front axles. Assume this is okay for a short drive.
- after that, will decide on new rear shaft followed by front...
Thanks for listening!!
- Removed rear shaft and drove. Still vibs. Pinion flanges are within 0.4 degrees. U-joints are tight, but not 100% free moving over complete range. Very minor play in slip joint.
- removed front shaft and drove. Still vibs. Ujoints are not loose and have free range of motion. Pinion and t- case flanges out by 4 degrees! How is that? I have the slee diff drop up front. That should keep factory pinion angles. Need to look at diff mounts to make sure nothing funny. They are tight.
- next step...maybe. remove the hub flanges that lock the front axles to the wheels and drive it on highway to see if vibs are related to the front axles. Assume this is okay for a short drive.
- after that, will decide on new rear shaft followed by front...
Thanks for listening!!
Hey guys...moving questions to the thread below...seems more applicable with lots of good info related to my specific issue...
forum.ih8mud.com
Pulsing/droning vibration at highway speeds
forum.ih8mud.com
Sorry for this dumb question, why we need a "Slee Diff Drop Kit." ? and could I install this to a stocked LC100 without any other modification?
Adventure Teq
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I'm quite certain no one would ever install a diff drop kit if they hadn't installed a suspension lift. The reason they are beneficial is because when you install heavier duty torsion bars, and crank them up to get the height you want, you are changing the angles of the CV joints. If you had brand new CV shafts installed at the same time as your lift then you wouldn't be as bad off as you would if you have aged CV shafts that have their wear patterns already internally worn in. Even with new shafts, the increased angles are not healthy for those components, and lowering the diff simply reduces that angle and generally returns it to near factory designed angles.
^^^
@HawkDriver nailed it. There is zero reason to run a diff drop kit if you haven't lifted the front end. Well, Christo would be happy to have you buy one, so I guess there is ONE reason.
@HawkDriver nailed it. There is zero reason to run a diff drop kit if you haven't lifted the front end. Well, Christo would be happy to have you buy one, so I guess there is ONE reason.
learned! Thanks for the explanation!
Fingers crossed, but I have my rear drive shaft out and will test to see if the vibration I experience at 70 will go away.
If it does, it makes more sense to buy a new DS than spend money on U Joints and a shop to press them in. I KNOW I can do it myself. But if I miss one step or do something wrong, like use the wrong thickness snap rings, then the vibration will be back and all that money spent will have been for nothing but more headaches.
IF I purchase a new DS, does it matter how it goes back in, in relation to the marks I made before removing the old one?
Update: rear drive shaft removed, still shakes like a mother.
As others have commented. The torque steer is quite something.
Repeating the process with the front shaft removed tonight.
Otherwise, I’m fairly certain it’s the tired 260k mile cv axles.
As others have commented. The torque steer is quite something.
Repeating the process with the front shaft removed tonight.
Otherwise, I’m fairly certain it’s the tired 260k mile cv axles.
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Badly worn Cv axles you’ll feel through the floorboard.
Is your truck stock? Does the rear view mirror vibrate when your driving to the point it’s annoying to clearly see behind you ? Do you feel the vibes in the seat, hands or feet? What’s the audible noise sound like? Noise or vibes on acceleration or deceleration? Speed dependent? What speed range?
The frames on these trucks resonate sound and transfer vibes making it difficult to pinpoint where from. Especially with aftermarket skid plates.
Is your truck stock? Does the rear view mirror vibrate when your driving to the point it’s annoying to clearly see behind you ? Do you feel the vibes in the seat, hands or feet? What’s the audible noise sound like? Noise or vibes on acceleration or deceleration? Speed dependent? What speed range?
The frames on these trucks resonate sound and transfer vibes making it difficult to pinpoint where from. Especially with aftermarket skid plates.
2.5" lift with diff drop and a bunch of other suspension stuff. Rear view mirror does not vibrate or shake, just the bull bar, the back seats, and I can feel it mostly through the floor. Not the brakes or steering wheel. I feel it mostly at 65 MPH + whether in neutral or drive accelerating or slowing down.
Update:
Just got back from a quick drive down the freeway, with the front driveshaft out in RDW mode, the vibration is just as bad.
I really feel like it has to be the axles at this point. You can just feel as you're getting onto the freeway creeping through 50 MPH that the front end particularly where the axles would be sound like airplane engines firing up with that deep rhythmic rumbling.
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Mine has started doing the very same thing. I removed the front drive shaft to test and still had vibes. Since it was out I went ahead and did the ujoints. Seems to have made the problem worse. Thinking CV’s at this point. I’m due for brakes soon, so I’m thinking change everything, brakes, CV’s, wheel bearings, ball joints, all at the same time. If I’m gonna take it down that far for the CV’s I’d rather only have to do it once.
That was my concern. That I would replace the U-Joints and it would be worse. With all the talk about using correct thickness snap rings I didn't want to risk not doing it right and just pay for a new driveshaft whether it was the front or rear.
I've been battling/ chasing similar vibes for a while now. Here's where I'm at:
Both front and rear shafts have been rebuilt/ balanced in the last few weeks. Engine mounts, trans mount, CVs are all new or pretty new.
Truck is smooth up to 45-50, then moderate to pretty heavy vibration begins at highway speed. Very much relative to throttle input. At some speeds, vibration is present during acceleration, and at other speeds it isn't. If it's not vibrating while acceleration, it vibrates pretty badly when letting off the throttle and the truck coasts.
Pulled front shaft. Vibrations are worse. Replace front shaft. Pulled rear shaft, vibrations are nearly gone, basically imperceptible. OK, let's dig in to the rear some more.
New u joints on the slip joint end (toward the diff) are quite notchy now. These joints are a few weeks old and have maybe 1,000 miles and one road trip on them. Joints on the other end (t case side) appear/feel fine still. I've very recently adjusted all of my rear arms to bring my pinion flanges within a few tenths of a degree of each other.
So I'm debating if I should try a new OEM rear shaft, or if there's possibly something in my diff that's causing joints to fail very quickly. IIRC, I had the same vibrations running my Tom Woods double cardan shaft as well. Rear view mirror jiggles quite a bit at peak vibration, and the feeling resonates through the whole truck at higher speed, 80-85+.
It's getting to the point that I don't want to drive the truck on the highway anymore, which sucks because it's my road trip vehicle. I definitely don't want to keep in it FWD mode because it torque steers like a MF on the 4.88s.
Both front and rear shafts have been rebuilt/ balanced in the last few weeks. Engine mounts, trans mount, CVs are all new or pretty new.
Truck is smooth up to 45-50, then moderate to pretty heavy vibration begins at highway speed. Very much relative to throttle input. At some speeds, vibration is present during acceleration, and at other speeds it isn't. If it's not vibrating while acceleration, it vibrates pretty badly when letting off the throttle and the truck coasts.
Pulled front shaft. Vibrations are worse. Replace front shaft. Pulled rear shaft, vibrations are nearly gone, basically imperceptible. OK, let's dig in to the rear some more.
New u joints on the slip joint end (toward the diff) are quite notchy now. These joints are a few weeks old and have maybe 1,000 miles and one road trip on them. Joints on the other end (t case side) appear/feel fine still. I've very recently adjusted all of my rear arms to bring my pinion flanges within a few tenths of a degree of each other.
So I'm debating if I should try a new OEM rear shaft, or if there's possibly something in my diff that's causing joints to fail very quickly. IIRC, I had the same vibrations running my Tom Woods double cardan shaft as well. Rear view mirror jiggles quite a bit at peak vibration, and the feeling resonates through the whole truck at higher speed, 80-85+.
It's getting to the point that I don't want to drive the truck on the highway anymore, which sucks because it's my road trip vehicle. I definitely don't want to keep in it FWD mode because it torque steers like a MF on the 4.88s.
Have you checked the pinion nut? My 40
Had a nasty vibration when I got off the throttle and I chased it forever. My pinion nut had worked loose enough to cause the vibration. Just a thought.
Had a nasty vibration when I got off the throttle and I chased it forever. My pinion nut had worked loose enough to cause the vibration. Just a thought.
No, but I will!
I took advantage of the sale at Mr. T of Decatur AL and bought a new OEM shaft for a deal. Let's see how this goes. Worst case, I have an extra spare now.
