HJ75 inconsistent driveline vibration

[HJ75]

Hi all.

I have recently been fighting with a very frustrating issue.
My 75 has an inconsistent driveline vibration.

This vibration only occurs over 95kph, doesn't matter if I am accelerating or not or even if I am coasting in neutral.
The part that confuses me the most is that it is inconsistent, it will go away for 30 seconds up to a few minutes, then come back, gradually get worse, then only vibrate lightly.

I feel this vibration in the seat base and can feel/see the gearstick vibrating, which lead me to believe it was drivetrain or towards the rear of the car.

To try solve this issue, I have already tried the following with No change:
-Rotate tyres, front to back
-Replace both universal joints,
-Replace driveshaft slip yoke
-Balance driveshaft
-Replace rear wheel bearings
-Inspect axle shafts- no bends or damage.

I have absolutely no idea what it could be now, so any help would be very much appreciated.
Thanks,

 

[pithicus]

Looks like you have tried just about everything. Can be frustrating. All I can suggest is replace each wheel 1 at a time with the spare and go for a drive. [ovaled,out of round tyers can cause vibrations]
Good luck

 

[mcmarshing]

Hey,

Have you checked the temperature of your rear wheels after driving?

I had a similar issue and it turned out to be:
1) worn out drum
2) brakes were slowly over tightening due to the bell crank adjustment bolts not accurately adjusted (0.6mm of clearance from brake backing with the adjustment cable tight)
3) worn out spring that wasn't releasing the drum shoes effectively
4) worn out auto-adjustment cable that was letting the cam/pulley (cam PN: 47626-60010, google it and you'll see what part i'm talking about) intermittently touching the rear hub. You'll see your dust boot shredded in specific spots if so.
5) letting my new tires break in (Falken AT3W)

 

[HJ75]

Looks like you have tried just about everything. Can be frustrating. All I can suggest is replace each wheel 1 at a time with the spare and go for a drive. [ovaled,out of round tyers can cause vibrations]
Good luck

Good thinking, I will give that a try.

Bell housing bolts were loose too, I have tightened them and just quickly tested it again on the highway.

I believe the vibration is still there, but I don't know if I am now just expecting too much from a solid axle leaf spring vehicle driving on poor Melbourne roads...

 

[HJ75]

Hey,

Have you checked the temperature of your rear wheels after driving?

I had a similar issue and it turned out to be:
1) worn out drum
2) brakes were slowly over tightening due to the bell crank adjustment bolts not accurately adjusted (0.6mm of clearance from brake backing with the adjustment cable tight)
3) worn out spring that wasn't releasing the drum shoes effectively
4) worn out auto-adjustment cable that was letting the cam/pulley (cam PN: 47626-60010, google it and you'll see what part i'm talking about) intermittently touching the rear hub. You'll see your dust boot shredded in specific spots if so.
5) letting my new tires break in (Falken AT3W)

Thank you that is very useful info, next chance I get I will check the temp of the drum.

I know my drums are old and grooved, and I have recently had the brakes apart to install new shoes and handbrake cable.

You may be onto something, I'll take a closer look at my rear brake set up.

 

[sodafeld1]

When I picked up my hj75 in Sydney driving back to Melbourne, it wobbled and vibrated sickeningly bad over 80kmh, New balanced tyres on the front fixed that in Yass. Old neglected split rims full of rust on the inside, rock chewed muddies, nasty. But it must have been like that for awhile as all the front bearings were worn and slopped out from the unbalanced tyres.

 

[HJ75]

When I picked up my hj75 in Sydney driving back to Melbourne, it wobbled and vibrated sickeningly bad over 80kmh, New balanced tyres on the front fixed that in Yass. Old neglected split rims full of rust on the inside, rock chewed muddies, nasty. But it must have been like that for awhile as all the front bearings were worn and slopped out from the unbalanced tyres.

Very interesting,
I brought the car with ROH sunraysia rims, I haven't touched the 31x10.5 r15 A/T tyres that it came with, I rotated the wheels front to back but the vibration seemed to stay in the rear so never gave them a second thought.

Might be time to invest in new tyres too....

 

[sodafeld1]

When I picked up my hj75 in Sydney driving back to Melbourne, it wobbled and vibrated sickeningly bad over 80kmh, New balanced tyres on the front fixed that in Yass. Old neglected split rims full of rust on the inside, rock chewed muddies, nasty. But it must have been like that for awhile as all the front bearings were worn and slopped out from the unbalanced tyres.

could be any number of things though..yeah find anywhere excessively hot. Time and love. Bearings came off like in the movies or stuck to axle housing? Shackles? tie rods? stabilser? springs? saddles for springs? Front bearings?
When I had vibrations it was the front, gear stick wobbled around and could feel it in the seat.

 

[pithicus]

I had a speed specific vibration with sometimes accompanying death wobbles. Tried everything, nothing helped, tyres rebalanced, rotated etc.Tyres weren't even half worn. I gave up. When time came for new tyres, it fixed it! And it never came back.

 

[HJ75]

could be any number of things though..yeah find anywhere excessively hot. Time and love. Bearings came off like in the movies or stuck to axle housing? Shackles? tie rods? stabilser? springs? saddles for springs? Front bearings?
When I had vibrations it was the front, gear stick wobbled around and could feel it in the seat.

I wasn't there when the wheel bearings were changed, but the old ones appeared ok I was told. They were clearly old with slightly worn races, but they never got hot on me before I replaced them.

I have now replaced all the wheel bearings as well as tie rods.

However it is worth noting that on occasion (in the wet) there is a clunk in the front end, I suspect this is the front shackle bushings, might somehow be related.

The rear leaf spring u bolts have been hit hard once in their life, 2 of them have had the threaded portion bent back.

 

[coldtaco]

sounds like your ute did not have a good life. I would replace front steering stuff, replace/repack front hubs. anything else that could be replaced. Make sure none of the springs are broken. Shackle bushings. Steering dampner/bushes.

 

[HJ75]

I had a speed specific vibration with sometimes accompanying death wobbles. Tried everything, nothing helped, tyres rebalanced, rotated etc.Tyres weren't even half worn. I gave up. When time came for new tyres, it fixed it! And it never came back.

Wow rebalanced the old tyres and the vibration still remained?
These have just under half their tread left but it might be worth the upgrade.

There is no way of telling what they have been put through before me...

 

[sodafeld1]

clunk in the wet is the front leaf springs, described as factory clunk, only time I didn't get it especially in the wet was with new front springs. Maybe re-springing them may work, but close to the same price here.

 

[pithicus]

Wow rebalanced the old tyres and the vibration still remained?

Yep, a couple of the tyres were slightly ovaled/out of round.

 

[HJ75]

sounds like your ute did not have a good life. I would replace front steering stuff, replace/repack front hubs. anything else that could be replaced. Make sure none of the springs are broken. Shackle bushings. Steering dampner/bushes.

You are certainly not wrong... I got it off a dairy farm so who knows what its been through.
The brake fluid in the clutch master cylinder had actually solidified when I first got it.

I knew that I was getting into unchartered waters when I brought it, so I have tried to replace most things, Front wheel bearings, tie rods, brakes and master cylinders, clutch were first to get done.

Shackle bushings (while appear ok externally) are next on the cards.

 

[HJ75]

clunk in the wet is the front leaf springs, described as factory clunk, only time I didn't get it especially in the wet was with new front springs. Maybe re-springing them may work, but close to the same price here.

I've heard that the front end clunk is very common like you say, apparently most just choose to live with it.

The vibration however has stumped several people that I have asked.

 

[HJ75]

Yep, a couple of the tyres were slightly ovaled/out of round.

Must be more common than I thought, will now look into some decent affordable tyres.

 

[sodafeld1]

a mechanic mate not attached to landcruisers, did point out that clunk noise is a sound that stresses metal, metal which is stressed and fatigued over long periods becomes brittle. did live with it for awhile though.

 

[troopydoopie]

Is the vehicle lifted? maybe you need caster wedges between the axlehousing and leafpack... ive got the same issue with my hzj75 and i reckon its the driveshaft angle that doesnt match anymore. I ordered a angle gauge to find out if thats the issue.

 

[HJ75]

Is the vehicle lifted? maybe you need caster wedges between the axlehousing and leafpack... ive got the same issue with my hzj75 and i reckon its the driveshaft angle that doesnt match anymore. I ordered a angle gauge to find out if thats the issue.

Vehicle has been lifted 2 inches I believe.
What is the driveshaft angle supposed to be on a 75? Once your angle gauge arrives, I would be very interested to hear how you measured it and determined if it is wrong.