Bad Vibrations

[ABryan]

Here is the situation... I have a 99 4runner SR5 v6 auto 4×4. i have replaced the calipers & rotors. I have turned the rear drums and had all 4 tires balanced and road force balanced at the dealership. I have a slight vibration (it feels like drive train, not wheels) at 70 mph and up. The vibration does not necessarily get any worse off with the increase speed but remains mostly the same (if it is worse, it is very slight) Once I had 300 lbs (or so) in the back and the vibration was worse but at the same speeds. The dealer is telling me they do not know what the problem is but it will be a lot to find it and fix it. They think it is the drive shaft... Any thoughts Ya’ll???????

[Seanz0rz]

i vote for rear ujoint. get under and check for excessive play.

[MTL_4runner]

i vote for rear ujoint. get under and check for excessive play.

Ditto.....I'd get under and check for excessive play.

[ABryan]

Ya I have checked that and all is well. i keep it well greased... I did have a drive shaft problem a few months ago where there was dried grease in the slip yoke from the previous owner. Once new grease was in place the sloppiness left. vibration still there...

[Good Times]

maybe your driveshaft is not balanced. may want to check that too.

[Cebby]

Do you see any excessive oil/grease at either the rear diff pinion or at the rear t-case output?

I'd take it to a driveshaft shop. Have them pull the rear shaft and check it for trueness (and check the u-joints too). It might even possibly be something with your pinion flange.

When you started noticing this, did you by chance carry a really heavy load in the cargo area?

[Lee]

maybe your driveshaft is not balanced. may want to check that too.

AGREED, check to ensure the weights are on.

[ABryan]

So the saga continues... i just got my driveshaft back from Patterson's driveshafts and i had it balanced and fazed. they said it was out of balance more then they expected... The vibrations seem to have left or reduced but now there is a loud low rumble from the rear. Any more ideas???

[Small_words]

I had a significant vibration when upwards of 45 mph and it would go away if I engaged the clutch. I had a bad U-joint and it was simple to fix. If I remember right, there are only (2) U-joints on the rear driveshaft that you can replace, the other (2) are funky types and if they're bad you have to replace the driveshaft entirely. Anyone else know different?