Are you sure it's the Birf?

[Dave 2000]

Well I started this thread because it could save someone a lot of money? Many of you are aware of my
https://forum.ih8mud.com/80-series-tech/365673-my-lc-80-thread-2.html

Well at post #48 shows some very strange wear patterns on the birf, it has been hitting the INSIDE of the birf 'chamber' where the grease is ect? It appears that the bronze bush inside the spindle carrier has worn really bad and it allows the birf to not only twist but also puts additional load on the CV joint which can cause it to click ect when turning under load in partuclar when the lockers are engaged?

This unwanted movement can also contribute to wearing the oil seal in the axle and causing it to fail in a very short time. Why mine shows this wear is a mystery, FSH (with receipts ect) and a verified 183,000 miles, this particular side was leaking quite badly whilst the other side was bone dry i.e. no leaks but full of grease. I have already assembled the other side but still may strip it down again to check the bush , this is my own fault I should have checked during cleaning ect, having said that I have had NO noises from anywhere at the front, my advise is before you go spalshing out on new birfs I would check the running clearance of the birf in the spindle carrier first.

regards

Dave

 

[IdahoDoug]

A couple thoughts on this. Offcenter/excessive inner oil seal wear can be caused by several things:

1 - A bent axle housing
2 - Destroyed knuckle bearings allowing the knuckle to flop around
3 - A birfield joint that has excessive wear and allows the axle to flop around.
4 - A worn bronze bushing in the spindle that allows the axle to flop around.

These same factors could allow the birfield to grind against the birfield chamber as your photo 48 shows. So the odd birf wear on its edge could have been the result of a number of past sins by the previous owner. I would agree with you that the bronze bushing would be a first thing to replace during a repack to help control birf movement.

Having said that, I'm surprised that nobody pointed out the horrible condition of your birfield in #48. Quite plainly, there is a chunk of steel missing from the cage where the ball contacts it and this is very, very bad. That birfield should not have been reused even if it is the only chunk missing (I suspect there will be others). My guess would be that the birf itself has a lot of slack in it, allowing for unwanted movement that will quickly wear a new bronze bushing (itself designed only for occasional contact, not constant control of the axle stub) and inner oil seal.

DougM

 

[Dave 2000]

Whilst I wil be replacing the joint Doug, you mention the bronze pushing is for occasional contact only? I think it's design and position would indicate more than occasional contact, there is a support inside the axle casing just behind the oil seal and then the next area of support would indeed be the bronze bushing right? The flange at the end of the birf i.e. the one held on by 6 cones/washers/nuts ect would not be capable of supporting the joint other than centering it leaving just the bronze bush to support the rest of the birf or am I missing something here?

I have put the shaft on 'V' blocks and it is showing no significant 'runout' so that leaves me (us) that the birf and housing has been run dry at some time in the past. I do not have the facilities to check the axle for straightness but there is nothing that jumps out at you, I would also keep in mind the previous owners occupation as a surgeon and the faultless service history would indicate a no expense spared type of ownership, so how has this occured?

regards

Dave

 

[IdahoDoug]

No clue how any of these might happen, but obviously 180,000 miles is a long time and either an accident or sliding heavily into a ditch could bend the housing, etc in terms of a bent housing. Not saying that's what you have as I doubt it. As for maintenance, it's worth noting that even Toyota dealerships do not always know how to maintain a LandCruiser properly. Many dealership repacks have been noted here on Mud without replacing the inner axle seal for instance. Most dealerships have no clue the rear wheel bearings need repacking (bet yours have never been touched), for another.

As for the front axle shaft support. That ring support behind the axle seal is only there for aligning the shaft while it's being supported and it should NEVER touch that support once it's assembled. The axle shaft is supported by the splined tip at the drive plate you call the 6 cones/washers, etc. Then in order moving inboard the bronze bushing partially supports the spinning axle shaft more to control its movement. The axle is said to be "floating" in that bushing - not rubbing hard against it. When the axle is turned for steering, I suspect the axle does rub against it under torque when the birfield causes axial movements (outward flexing due to the joint's neccessary design). Then the axle shaft is entirely unsupported all the way to the differential.

The key is the birfield joint in the axle being able to run true while unsupported for all this length. If it is new and tight there will be little axial movment. As it wears, there is progressively more and more movement and play which come to bear on the bronze spindle bushing - running against it even with the steering straight, etc. This movement also tears up the inner axle oil seal as the shaft wobbles against it.

So, the entire drive shaft is essentially supported at the splined tips where it enters the drive plate and the differential with the bronze bushing there to limit movement under heavy load or while steering sharply.

The diesel models have a roller bearing in place of the bushing in deference to the greater torque of this engine being able to distort the drive shaft more easily under heavy loads. The bearing is designed to handle more frequent and greater loading. Here in the US, we can get this bearing and I think it's something to consider for you if you don't replace the birfield. The bearing can handle the greater load of a loose birfield than the bushing would.

DougM

 

[Dave 2000]

Thanks for clarifying that Doug, mine is a diesel and yet there is no roller bearings? The picture at the dealership was the same the broze one I have fitted but again the pictures are not alway right, I will be picking up the bush tommorow along with a set of big end bolts ect.

Re the dealers not knowing how to service their own cars I hear you buddy, it's not just Toyota either!

Re the rear axle I went through the printouts and guess what?......your dead right!! The nearest that a mechanic got to that was changing the brake pads, not an issue for me though I will put it on the list.

many thanks

regards

Dave