New Vibration (1 Viewer)

[franken60]

Looking for some advice on a vibration issue I've started having.
Truck specs:
1981 bj60 turbo
SOA
37" tires with balancing beads
456 gearing
H42 trans

So I've got a vibration at almost all speeds. Upon accelerating past 2md gear there is a very faint vibration, once holding/maintaining a speed (30-90km/h) it becomes more prominent. There worst I've found it is decelerating from 40km/h in 2md gear, feels like I'm driving on rumble strips. Joints seems fine though there is a slight squeeks at parking lot speeds.

I recent had the Pinion bearing replaced professionally, and regressed the rear wheel bearings. New fluids in the diff. Fluids in trans and Tcase are 9months old with less than 15k on them and are at appropriate levels.

I've had ujoint problems in the past and it's always a good place to start but this feels different. There no clunking or clanging when changing gear, pulling away from a stop or going into reverse.

Thoughts?

 

[mattressking]

Can you disconnect rear axle and run it in fwd and see if the vibration changes?

Before pinion was serviced, was the issue occurring?

 

[franken60]

Can you disconnect rear axle and run it in fwd and see if the vibration changes?

Before pinion was serviced, was the issue occurring?

I could try that ya, but it's never run on the road well in fwd, angles a bit steep with the 4speed.

I'd vibrated a bit maintaining highway speeds but nothing to this extent. It's been almost 2 months of consistent driving since the rear diff service

 

[BlackCat]

Decelerating vibration in my experience is pinion angle. It can also be tire balance as well. Easy thing to do would be to swap some smaller wheels and tires from a buddy and go drive it real quick.

 

[Seth S]

Try smaller tires with traditional balance weights first. Tires and tire balance are like blown fuses. Most likely moving vibration culprit

 

[OSS]

I bet it's the tires with those dynabeads inside em

 

[franken60]

Decelerating vibration in my experience is pinion angle. It can also be tire balance as well. Easy thing to do would be to swap some smaller wheels and tires from a buddy and go drive it real quick.

Pinion angle hasn't changed in 6 years

 

[franken60]

Try smaller tires with traditional balance weights first. Tires and tire balance are like blown fuses. Most likely moving vibration culprit

I bet it's the tires with those dynabeads inside em

Possible but they've been the most balanced tires over ever had, and haven't let me down in 3 years
Gotta get a patch and stems changed anyhow. Maybe get the beads changed as well.

Heard some more defining snaps and pops when pulling away from a stop this morning though

 

[Seth S]

Grease all your joints?

 

[franken60]

Grease all your joints?

Ya they've been greased a couple times recently

 

[Seth S]

You might also just try moving the from tires to the back and backs to the front and see if the vibration changes.

 

[stevebradford]

Hey buddy!

So I've got a vibration at almost all speeds. Upon accelerating past 2md gear there is a very faint vibration, once holding/maintaining a speed (30-90km/h) it becomes more prominent. There worst I've found it is decelerating from 40km/h in 2md gear, feels like I'm driving on rumble strips. Joints seems fine though there is a slight squeeks at parking lot speeds.

Decelerating vibration in my experience is pinion angle. It can also be tire balance as well. Easy thing to do would be to swap some smaller wheels and tires from a buddy and go drive it real quick.

Agreed with BlackCat but you didn’t have issues before the work done, hopefully they didn’t cock up your pinion preload..

Does the deceleration vibrations change when you are in gear using the motor hold back to slow you down vrs coasting?

If it’s still vibrating the same when coasting it’s a lump in the tires, bad balance or loose wheel bearings. (Those Toyota full float axles like tight wheel bearings in my opinion)

If it’s the hold back causing the deceleration vibes it’s pinion, ujoint or tcase output bearing.

Can I ask what shop did the pinion work?
Feel free to text me if you need to borrow a set of rollers to try, the wheel bearing tool or just a beer.

 

[cruisermatt]

I've had bad/loose pinion bearings that have caused similar symptoms. What where the circumstances that led to you having the rear diff serviced in the first place?

 

[franken60]

I've had bad/loose pinion bearings that have caused similar symptoms. What where the circumstances that led to you having the rear diff serviced in the first place?

I had it serviced due to worn pinion bearings. It has 3/16" slop all around. New bearings, crush washer and seals. Professionally done. I reinstalled the carrier and wheel bearings as per the FSM and drove it daily for a month roughly 70-120km per day with no issues

 

[cruisermatt]

Let’s try that again.

What where the circumstances that led to you having the rear diff serviced in the first place?

Did you have any issues before you had the rear diff serviced? What made you decide to have the rear diff serviced?

 

[KWalkerM]

My experience with literally the exact same setup says U-joint or rear pinion. Make sure it has adequate fluid by filling on an incline rear pointed up. Also check motor mounts and transmission mount.

After that check for front end slop in the TREs and alignment. Sounds dumb but that was a contributing factor on mine by not having adequate toe in/out creating wobble on the 37s.

 

[franken60]

Let’s try that again.

What where the circumstances that led to you having the rear diff serviced in the first place?

Did you have any issues before you had the rear diff serviced? What made you decide to have the rear diff serviced?

Ah ok. It was squeaking and and making some light clunking noises. I crawled underneath to check ujoint and found that the pinion had play along with fluids leaking from the Pinion seal. I removed driveshaft and checked it again to confirm it was bad. The shop also confirmed that the bearings were worn. Not sure what else to tell ya, had play, made noise, wasn't tight, got it fixed

 

[franken60]

My experience with literally the exact same setup says U-joint or rear pinion. Make sure it has adequate fluid by filling on an incline rear pointed up. Also check motor mounts and transmission mount.

After that check for front end slop in the TREs and alignment. Sounds dumb but that was a contributing factor on mine by not having adequate toe in/out creating wobble on the 37s.

I'll check fluid levels in the diff again, filled it properly and hasn't leaked at all though. As for mounts, new engine mounts and trans mount within the year, all factory, no aftermarket.

I've had Tre issues in the past with factory components and upgraded to gm 1ton on a 4x4 labs system. Truck drives straight with minimal to no wandering, steering is tight.

 

[cruisermatt]

Ah ok. It was squeaking and and making some light clunking noises. I crawled underneath to check ujoint and found that the pinion had play along with fluids leaking from the Pinion seal. I removed driveshaft and checked it again to confirm it was bad. The shop also confirmed that the bearings were worn. Not sure what else to tell ya, had play, made noise, wasn't tight, got it fixed

Ok, mainly what I was getting at was that your current issue has different symptoms then your previous pinion issue.

I’d be looking at driveline, pinion, T-case output. You can pretty much check all three at once.

 

[KWalkerM]

I'll check fluid levels in the diff again, filled it properly and hasn't leaked at all though. As for mounts, new engine mounts and trans mount within the year, all factory, no aftermarket.

I've had Tre issues in the past with factory components and upgraded to gm 1ton on a 4x4 labs system. Truck drives straight with minimal to no wandering, steering is tight.

Ha. The only difference in our trucks is powerplant and I have a cage. I have chevy 1ton TREs as well. But yeah front end slop and a broken U-Joint and a bad lower pinion all gave me wobble on seperate instances like you described