Driveline question: UJoint/DC/Tranfer Output?

[gabenguyen]

Hey Everyone, New to the board overall and have been chasing down a vibrating issue others seem to have had.

I have replaced both my CV axles think that was the issue. I then thought possibly needle bearings but stumpled more closely to U-joints.

My issue is that the car seems to vibrate and hum once I get to about 60-65mph. At about 70, the vibration tapers down a little and is not as noticable going any quicker.

within that sweet spot, it also seems to ease off when I release the throttle.

Alot of people have said it was symptoms of U-joints but probably wouldnt need to replace all of them.

2001 SR5 AWD with abotu 350k miles

For the sake of not fixing all of them, I went under to check. The rear driveshaft and u-joint seem solid. The DC also seems solid but I noticed there was about 3mm of play. It looks like its coming from the transfer case output flange.

I saw the front driveshaft. Someone on the boards said there were 3 u-joints, but Im not entirely sure what Im looking for. I checked both ends of the driveshaft for what I believe to be the u-joints and there's no play. Im not sure where the third one is.

Going back to the output flange, has anyone experienced this? What should I prepare for? Rather than buying a bunch of stuff and chasing another problem, what do you think it would be? Also, if im in there, what should I just replace anyways?

My train of thought is to buy a new flange; and possibly a seal and bearing?
Also maybe just only the flange since its not that intrusive of a replacement; and if the problem persists, consider getting a new bearing or even transfer case

Here's the video:
https://www.youtube.com/watch?v=S9yIY8lfnqw

 

[NachesPass4x4]

My experience is all with the gear drive cases but in my experience a little up down play in the flange is normal. Even with new bearings.
The front driveline has two u joints, the rear has a u joint and a cv joint. To really inspect them, after inspecting on vehicle, you can remove the shaft and see how they feel. You could replace the rear u joint and test drive with the front shaft removed to rule it out.

My 2000 4runner chain case has like 1/16" in/out play. I've never seen that and not familiar enough with the chain case to know what would cause it.

EDIT: Didn't see the video until after I posted. That definitely looks like more play that what is normal. Was that movement making noise?

 

[NachesPass4x4]

My train of thought is to buy a new flange; and possibly a seal and bearing?
Also maybe just only the flange since its not that intrusive of a replacement; and if the problem persists, consider getting a new bearing or even transfer case

Here's the video:
https://www.youtube.com/watch?v=S9yIY8lfnqw

You need the bearing and seal. The only thing that really goes wrong with the flange is the seal can wear a groove into it so you can never get a good seal. With high mileage that will likely be what you find and need a new flange also.

There may be more to this than just the output bearing, I'd be curious what others have to say

 

[gabenguyen]

My experience is all with the gear drive cases but in my experience a little up down play in the flange is normal. Even with new bearings.
The front driveline has two u joints, the rear has a u joint and a cv joint. To really inspect them, after inspecting on vehicle, you can remove the shaft and see how they feel. You could replace the rear u joint and test drive with the front shaft removed to rule it out.

My 2000 4runner chain case has like 1/16" in/out play. I've never seen that and not familiar enough with the chain case to know what would cause it.

EDIT: Didn't see the video until after I posted. That definitely looks like more play that what is normal. Was that movement making noise?

Thanks for the clarity. Apologies for the vehicle that drove by in the video but pushing the driveshaft up and down does have an audible noise. You can pick it up in the video

 

[gabenguyen]

You need the bearing and seal. The only thing that really goes wrong with the flange is the seal can wear a groove into it so you can never get a good seal. With high mileage that will likely be what you find and need a new flange also.

There may be more to this than just the output bearing, I'd be curious what others have to say

Appreciate it. Preparing for the seal, bearing and flange makes sense.

If suspected to be more, do people typically just replace the whole transfer case?

 

[alumarine]

I had a vibration that I couldn't figure out.
U joints on front and rear drive shaft seemed ok.
I disconnected the rear driveshaft and drove it in 4wd.
I only had to go about 100 feet when it was obvious it was the front drivesahft.
For some reason with the rear attached it reduced the front vibration somehow.

 

[NachesPass4x4]

Appreciate it. Preparing for the seal, bearing and flange makes sense.

If suspected to be more, do people typically just replace the whole transfer case?

I probably shouldn't have mentioned the possibility of there being more going on because I dont know that. I was just surprised to see that much movement and that you could actually hear it. I think you are on the right track with the output bearings.

As for rebuild/replece, I have only worked on the old RF1A gear drive cases. If it was one of those I would rebuild, if needed. They are pretty simple and the bearing kits arnt too expensive. I dont know what kind of work/$ goes into the chain drive cases or what they go for used. Hopefully they arnt too complicated.

 

[ninethings]

I chased down a very similar issue a few years ago. Would get a vibration/chatter under certain load/rpms. Replaced the needle bearing with a ECGS clamshell bushing, replaced both CV's, greased the driveline, no noticeable play outside of allowance, etc.

This may add nothing to the thread, it may. But in 01-02's with the A340F auto transmissions, there is a failure point in the throwout bearing in the overdrive planetary gear. That was unfortunately the issue with my rig. Only stumbled on it after replacing the needle bearing with the clamshell. Got out of the garage and on to the road and for whatever reason, after hearing the chatter persist, hit the O/D OFF button and the vibration/chatter disappeared. Limped it around for a few months with O/D off before I had the trans rebuilt by YOTA1. I really hope this isn't the cause of your mystery vibration (as its the most expensive conclusion) but try clicking the O/D button next time you hear/feel it and see if there is any discernable change. Good luck

 

[gtx13]

I know this thread is a little old but I'm also getting play in the t-case output flange. There's a staked nut which holds down the flange, remove the driveshaft and check if it's loose. Some people have reported they were finger loose and causing the vibration. Here's a video showing it:
- YouTube

Mine still seems tight, but I will try tightening it down later and see if that removes the play. It should be torqued to 87 lb/ft, iirc. If you want to be thorough, unstake the nut, install a new nut and then stake it

 

[gtx13]

Update, after torquing down the nut to spec it has removed 90% of the vibrations. Prior to tightening it, the stake/witness paint mark were aligned. After tightening, they're slightly off-center. In the photo, you can see how the stake nut has shifted slightly clockwise, enough to remove the play on the flange.

My 4Runner has 288k mi and is nearly 30yrs old, so my best guess is that gradually over time the bearings or something developed play, resulting in the looseness. As I just bought it recently, I have no idea how long it was like this for.

 

[BuffaloBass]

PS Those nicely done OEM studs that surround that flange are no longer avail BTW. I found one where the knurling was beat up pretty good, maybe by being loose.

PSS while swapping out ujoints in the forward shaft was easy, it was impossible in the main shaft. The double Cardon (?) joint was whacked so couldnt remove either of the front 2 ujoints. Beat the snot out of it trying too. Ended up having a new shaft made at Fleet Pride. Real nice work!