Topic: (not so good)vibrations 2006 Dodge ram 3500

[BLACKDOG]

Curious on your thoughts as far as what this could be. 

I get a vibration when I hit 25 mph in my truck.  The vibes go away completely between 35 and 40 mph. It definitely feels like its coming from the back. 

I checked the driveline, no obvious weights missing, ujoints seem to be tight.  There is some movement from the carrier bearing, but it is very minimal, and seems to be just the rubber flexing.  I haven't pulled the driveshaft, and it is still indexed correctly.  Strangely, it seems as if this happened over night.   I haven't checked the wheels out closely, but they shouldn't be out of balance at all.
thoughts?

[fordh8r]

U-joints may be tight but are you sure you don't have one that may be seizing up on you?  I had one doing something similar on my Toyota recently. Only, it vibrated at around 45-50 and then went away. Then it wasn't til way later that it started squealing real bad before I realized what was going on.    Weird part was that of the 4 cups on the cross, three were perfect and well greased and the fourth was bone dry and all galled up. 

[Blingn]

my ford threw a weight on one rim and it would shake at only 45 mph up.  good luck on the diag

[BLACKDOG [OP]]

Oh, and a bit more info:

manual transmission
doesn't happen based on rpms, just speed
doesn't happen in 4wd

[junya92toy]

Tire balanced?

[BLACKDOG [OP]]

U-joints may be tight but are you sure you don't have one that may be seizing up on you?  I had one doing something similar on my Toyota recently. Only, it vibrated at around 45-50 and then went away. Then it wasn't til way later that it started squealing real bad before I realized what was going on.    Weird part was that of the 4 cups on the cross, three were perfect and well greased and the fourth was bone dry and all galled up. 

WINNAR!!  This was exactly it.  It was nice and tight, pulled the driveshaft, and it was still nice and tight.  did a close visual inspection, and the only thing that tipped me off was that 2 of the caps on the ujoint had a bit of grease coming out, the other two had none, and had barely visible bare metal. 

Oh, and that new(ish) injected retaining method? PITA!

[fordh8r]

Nice!

As for that injection retainer, I usually just heat them up and when that stuff melts and expands it will ooze out of the injection holes like a massive Zit being popped in slow motion!

[superyota]

Oh, and a bit more info:

manual transmission
doesn't happen based on rpms, just speed
doesn't happen in 4wd

does it do it in all gears or only a certain gear?  i'm wondering if it might be a bearing in the trans or tcase.

[Hunterwarren]

My 2500 does something like this I can feel floor vibrating and it loses power around the same speed I have a 2000 dodge ram 2500 5.9 liter gas with auto transmission any ideas would be great

[fordh8r]

Dropping the driveline and checking the U-joints seems to be a good place to start.