Bad juddering after running 60mph

[Gregh]

Hi everyone,
I'm hoping someone will know what is going on with my 1996 24v Manual HDJ80R.
When I travel at around 55-60+ MPH it sometimes starts to judder badly . So much so that I need to stop, then it's OK again.
This has happened before, a long while back when it was new, and Toyota fixed it under warranty diagnosing the problem as the handbrake binding in the rear rotors.
Is this a known issue? Does it just need new rotors or could it be adjustment or brake service etc?
When it was new and under warranty the Toyota agent was always firing the parts canon at it so all new brakes and rotors was the fix.
However that was A LONG time ago and I did not have to pay, (or have much of a say in the matter), so I wonder if anyone has any experience of this before I get new rotors installed.
Regards to all
GregH

 

[Shayne]

seriously mismatched tyre pressures . Worn out universal joint . Sticking brake caliper .wheel alignment ?

 

[Towpack]

Sticking/binding handbrake shoes can give the symptoms you describe. It's more likely to happen after adjusting the handbrake and setting the shoes with insufficient free play as I have done a couple of times. Initially all seems well but the binding causes the brakes to heat up and you get a vibration through the drive train. Stopping and letting them cool down, the problem stops until they heat up again. Checking the shoes for binding is easy enough.
I'd expect a wheel balance or a propshaft/UJ problem to be there all the time, not just sometimes.

 

[Shayne]

Thanks for that Towpack I recently rebuilt rear calipers and fitted new rear discs , on doing a bit of distance today it was obvious somethings not right .

 

[Gregh]

Thanks everyone, really appreciate your help
Looks like I may have the rotors problem again but I will get the adjustments checked first
Cheers

 

[Shayne]

The handbrake works by spreading shoes that contact the inside of the rotor and it is properly adjusted by taking rear wheels off and using a screwdriver to turn a cog . Its very unlikely you will need new rotors .

 

[Shayne]

Come to think of it yours problem has evolved all by itself which is the opposite of typical , Cruiser handbrakes are renowned for slacking themselves off during off road exploits and needing tightening .

So look at the lever at the rear of your brake dust shield and i bet its rusted solid . At 13 seconds you get just a glimpse of a brand new one in this vid but to free it up and grease it will likely see you good for many years .

 

[Gregh]

Hi Guys
I got my local guy to take a look and he said the rotors & handbrake are OK but the rear prop UJ at the transfer box end has got slight play in it. (Both rear UJ's were replaced in 2023)

Driving the truck today the vibration came back again, (and it did seem higher frequency than the wheel speed when I think about it so looks like it is the UJ)
As usual I stopped, waited for the traffic to pass, and when I started off again and it went away!?
I did not think UJ's went bad like this. The experience I have is they vibrate and moan under load until you replace them.
Anyway, thanks for the help and advice. VERY much appreciated
Regards
GregH

 

[Shayne]

First sign of UJ on the way out is vibration in the rear view mirror at speed I reckon . Has to get much worse before you feel it

 

[Tachycardic]

Make sure you check your nuts. Knuckle nuts that is. I believe that they should be torqued to 71 foot pounds (96.3 Nm).

 

[Volly]

Sticking/binding handbrake shoes can give the symptoms you describe. It's more likely to happen after adjusting the handbrake and setting the shoes with insufficient free play as I have done a couple of times. Initially all seems well but the binding causes the brakes to heat up and you get a vibration through the drive train. Stopping and letting them cool down, the problem stops until they heat up again. Checking the shoes for binding is easy enough.
I'd expect a wheel balance or a propshaft/UJ problem to be there all the time, not just sometimes.

I’ve had the handbrake issue, combined with non-aligned wheels. Did exactly this.

 

[essexpete]

I would doubt a worn UJ on the prop would be intermittent.

 

[frank rabbets]

Sticking brake shoes on the rear maybe your problem. Terrible juddering. I would slacken them off and remove the drums to make sure the adjusters are not seized and that the shoes are able to go right back. (ie. Pull off the brake drum when the handbrake is released).

 

[Gregh]

Well I now have the brakes and the UJ's sorted and as you suspected it has not cured the problem.

The general consensus from the garage mechanics who worked on the UJ's and brakes, (and admit they are not experienced with a Landcruiser), is that it is the front differential.
They are probably right because it has been worked on numerous times in the last couple of years.

Do you guys have any advice as to where to go for a replacement?

It's a manual HDJ80R and I have been told the diffs are very hard to find so any advice most would be most appreciated.

Regards
GregH

 

[Shayne]

https://www.4x4works.co.uk/product/terrain-tamer-differential-rebuild-kit-toyota-land-cruiser-fj-fzj-hdj-hzj-80-81-series-1990-98-diff-overhaul-front/

Take it to a gearbox specialist preferably one who works on hgv stuff

 

[felix2566]

I'd be surprised if the diff needs to be replaced. More likely a rebuild. But I'd imagine there would be noticeable noise and lash in the system if it was that bad.

 

[frank rabbets]

If the prop splines have been separated it could be the phasing is out. I assume it's not wheel balance?

 

[Shayne]

Tyre wear might offer some clues ?

 

[Gregh]

Hi Folks,
I agree with all the comments that the diff should not need replacing.
Also agree with Shayne that a re-build would be in order, but this has already been done using mostly genuine bearings and seals from Rough Trax and a new Crown & Pinion kit from Oz via eBay.

The thing is that this diff has a history and I do not know what it was before it appeared on my vehicle, and that is a whole other disappointing story that precedes this current situation, (I could relate the chain of events for you guys but I am sure you would not believe me!)
I just had a retired engineer spend a bit of time to check it out and he thinks there is a noise from the front diff and he points out that the juddering always occurs after extended deceleration such as slowing down from speed or down a long hill using the engine braking. His advice is the same. Get a specialist engineer to take it apart and see what is going on

I think I may have been foisted with a problem diff, and trying to fix it is flogging a dead horse. Consequentially this makes me think I think it would be better to get a refurbished replacement, or a second hand unit to re-furbish. Currently I am wondering about the possibility of getting a second hand differential with a locker from an automatic vehicle, (I believe they are available), and swap the manual ratio gearing into the replacement carrier.
Does anyone have experience of this route or know if this is possible?

 

[frank rabbets]

An in cabin video might help. I would quadruple check that the rear shoes are backing right off when hand brake is off. What was the very last work done before the problem occurred?