Vibrations in drivetrain?
- Thread starter Chrash
- Start date
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Did you check the U-Joint play with the driveshafts UNLOADED? Everything you describe points to a U-Joint.
Find a deserted alley with buildings on each side. Slowly drive the vehicle down the alley with the window open. If you hear a 'click, click, click': You've got a bad u-joint.
If you've already done the wiggle test, have you checked your tires/wheels? You might have slung a wheel weight.
If you've already done the wiggle test, have you checked your tires/wheels? You might have slung a wheel weight.
It is normally over greasing the sliders that can cause vibes, but of course no grease means they may be jammed. Just don't go mad while searching for problems, you do not want to add to them.
Regards
Dave
Regards
Dave
Ok go with this, pump a load in there (both shafts), then unscrew the zirks x2 and go for a drive, if you over filled grease will be expelled as the shafts expand and contract with axle movement, messy yes but a certain method to put you right.
Regards
Dave
Regards
Dave
By UNLOADED I mean....No booze in YOU! 
No, not really!
Unloaded on the driveline does NOT mean the wheels off the ground, although that certainly helps.
It means, set the parking brake, place the transmission in NEUTRAL, chock the wheels, THEN get under it. You SHOULD be able to wiggle the DS a little bit rotationally by hand. If you get vertical or lateral movement, the U-Joint is shot.
I always try to do this AT DRIVE HEIGHT (rather than on the stands) because that way it is in the "wear point" position. This is the place where the driveline NORMALLY operates and wears. When you take the weight off the truck and let the axles hang, the splined yokes will be in a tighter place because they on the UNWORN area of the shaft. Sort of the same with the U-Joints, but not as much.
ALWAYS grease the driveline in an UNLOADED state and at normal drive height, because otherwise, the grease goes to the UNLOADED side of the splines and not to the side that is wearing.
When you grease the slip joint (Splined yoke that allows the DS to telescope), only put in 3-4 pumps when it is in its NORMALLY OPERATING POSITION.
If you do it when it is EXTENDED (such as wheels off the ground) do as @Dave 2000 has said and unscrew the zerks to allow the grease to ooze out. There IS a hole in the center plate behind the U-Joint, but that is FREQUENTLY clogged. If you over grease, it will blow out that plate and that's worse. If you don't relieve the pressure and it doesn't blow out the plate, you can still hydraulic the bearings in your T-Case because the pressure cannot relieve.
Lots of threads here about this.
No, not really!
Unloaded on the driveline does NOT mean the wheels off the ground, although that certainly helps.
It means, set the parking brake, place the transmission in NEUTRAL, chock the wheels, THEN get under it. You SHOULD be able to wiggle the DS a little bit rotationally by hand. If you get vertical or lateral movement, the U-Joint is shot.
I always try to do this AT DRIVE HEIGHT (rather than on the stands) because that way it is in the "wear point" position. This is the place where the driveline NORMALLY operates and wears. When you take the weight off the truck and let the axles hang, the splined yokes will be in a tighter place because they on the UNWORN area of the shaft. Sort of the same with the U-Joints, but not as much.
ALWAYS grease the driveline in an UNLOADED state and at normal drive height, because otherwise, the grease goes to the UNLOADED side of the splines and not to the side that is wearing.
When you grease the slip joint (Splined yoke that allows the DS to telescope), only put in 3-4 pumps when it is in its NORMALLY OPERATING POSITION.
If you do it when it is EXTENDED (such as wheels off the ground) do as @Dave 2000 has said and unscrew the zerks to allow the grease to ooze out. There IS a hole in the center plate behind the U-Joint, but that is FREQUENTLY clogged. If you over grease, it will blow out that plate and that's worse. If you don't relieve the pressure and it doesn't blow out the plate, you can still hydraulic the bearings in your T-Case because the pressure cannot relieve.
Lots of threads here about this.
Head gasket
If your u joints are shot, grease may not make a difference. If your still chasing a vibration, remove the drive shafts so you can rotate the uni joints in every direction. They should rotate smoothly and freely in all directions, if they are excessively stiff, or notchy, they are done.
The roller bearings in u joints can be seized, and still feel and look ok while the drive shaft is bolted in.
- Thread starter
- #18
Finally got it greased up and took it out on the highway. It's much smoother. I'm hyper focused on vibrations now, still getting a some here and there, but it's much better. Thanks to everyone, I appreciate your help.
