Trying to diagnose a pulsing driveline vibration

Bearing cups on the u-joint should spin free when slid on 1/2-3/4 way on the joint bearing shaft portion. Pushing the cups on clear to the seals,,will cause the seals to rub on the u-joint body,,giving you a false feel,, and the best time to check them is when they are due for grease. With only 92K on them, I would wager a bet that they are fine. 208K on my original "99" joints all around and still smooth. They started tossing service grease onto the floorboards at about 100-125K,,so they get greased at 1500-1700 mile intervals,,then the full service happens at 3000. Your rear differential joint is the one that takes the most abuse out of all of them,,from road deposits getting blasted on it during the wet.

 

I bet it is the need bearing, in front diff. Sounds like what many of us with this issue experienced. Will link it in a few when I get home.

Here, read this, your 'goes away in 4hi' is a big red flag pointing this direction:
http://www.tacomaworld.com/forum/1s...1st-gen-4x4-front-diff-bearing-vibration.html

Edit: disregard, I derped and misread the postings and thred (never walk and tapatalk), good luck with your diagnosis

 

Did that solve your vibration problem?

 

I just got it in the mail friday and its been snowing. Not sure when I will have time this week as I am a full-time student with a full-time job lol. I will post when I get it installed!

 

Any update with this, I have the same problem in my 08'. Its the same pulsing vibration about every second. Except mine quits when I make a right hand turn (switching lanes). I've been trying to figure this out for months now.

 

After the installation of the new bearing my pulsing vibration at low speeds is gone. But if your vibration stops when you make a turn I would vote on a bad wheel bearing.

 

+1. And that can go both ways. It will either stop vibrating or get severely worse,,in which case, carefully slow down and pull it over, let it cool down on it's own.

Just drifting over in a lane change is not a huge angle of attack change most of the time, but it could definitely be a wheel bearing.

 

Thanks for the help. I didn't think it would be a wheel bearing because I only have 106k on the truck. That seemed premature for a 2wd truck to have front bearings going bad

 

well I haven't posted here on here in a while. But my problem never really went away. A few days after I got the new carrier bearing and a new u-joint on the rear drive shaft (had a tight spot in it) the vibration/sound came back. I now realize that was just a coincidence because I have now discovered what my vibration is. The front driveshaft is spinning in 2 wheel drive. Anyone have any ideas why or how this is happening? No power is being put to the front wheels it just spins over about once every second or so. I can crawl under the truck and easily turn the driveshaft with my hand while the truck is parked and in gear. Any ideas?

 

Don't know how I missed this thread, ok, first off the turning of front shaft is pretty normal while going down the road,its centrifugal force, more so with A.D.D. types than a standard "get out of truck" to lock the hubs.. Actually, a fair amount of movement/play in the Carrier is considered normal, Prolly been asked a thousand times already so I'll ask again are you sure the rear driveshaft is straight ??Balanced ?? No chance it threw a weight ?? rare but it happens..

Pulled axles to check outer bearing yet?? That could be it too possibly, ya might as well, change the seal its due.. Sometimes wheel bearings will act this way, when they wear into the race, it gets deeper & the bearings start to "egg shape" that can cause a warping wobble in rotation, dont think its going to be a pinion losing its bearing or preload, you'd have heard something, get a cam mounted somewhere far end of bed, underneath so you can view behavior of driveline, tires/wheel/axle movement....thays all i got for ya dude

 

Hey
kckrawford!
Did you manage to figure out the cause of your vibration problem?
I think I have the same issue with my truck.

 

Any update on this?
Thanks!

 

DO NOT rotate the driveshaft on its splines. There are several paint marks/dabs on these shafts (mine had white paint dabs), just make sure they are lined up perfectly so the universal joints are in 'phase'. If not, vibrations will ensure....the weights on the shaft pieces can be anywhere on either shaft, they are balanced separately, then aligned and assembled for a final balance check. Not unusual to see weights in various spots as they are not intended to line up...

Believe me when I tell you I have spent a maddening amount of time understanding these long two piece driveshafts...

Pay attention to your angles, there are three of them to measure, front of shaft coming out of transmission, middle of shaft, end of shaft to third member. If any of these are not in spec, then you have to use shims and washers to bring all back to 'right'.

Since you have a 4 wheel drive vehicle, it could be the bearings up front....do a search, you will find all sorts of informations on that problem...