Rebuilding the 80 series front axle

[karl webster]

Defo cris
There is a bloke who used to work at toyota who has his own garge in derby now. If i remember i will get someone i know who goes there to ask him as i would like to understand myself. I do know that You have the small bearings at the top and bottom holding the hub in place.
I will have a better look when i Put new seals and bearings in my 80 so i can try and understand whats what. I will pack with grease i think though.
I seem to have to tighten my bearings up very often on the 80 as well even tho ive fitted new within the last couple of months. I know im running spacers but ever 80 i have i have to nip them up.
Also had to tighten the o/s on the 100 tonight. But bearings are another topic
karl

 

[Chris]

All part of the hub rebuild topic though Karl. I have done mine several times now for different reasons and every time I come to them, the pre load is still spot on. Happy to come over some time and look at how you are doing them. I set mine with some electronic scales. Seems to work every time.

Chris

 

[karl webster]

Each 80 i buy cris has to have the bearings looked at for mot. The truck dave had off me had the bearing issue with it. I think the 80s just follow this pattern.

As for the 100. It was always maintained to a high standard as it did alot of heavy toing with 3.5t behind it. Ive probably done 1000 miles in it and had to nip the bearing up already.

What do you mean by scales mate?

Thanks karl

 

[Chris]

For setting the pre load on the bearings mate. I use small electronic scales to get the break away load on the hub. That is to say, how much force is required to get the hub to turn against the friction of the bearings etc. They shouldn't just spin around nor should they bind excessively. I use the scales to get them exact.

Chris

 

[Jon Wildsmith]

I changed the front axle on my old 80, for a brand new casing bought at the main steeler not long after I got it, due to pitted swivels, that might be the one you've heard about Karl

I think the swivel being full of grease and topped up is:

lubricate the bronze bush in the base of the stub axle
keep putting a coating of grease on the swivel helping to stop it corroding
helps delay the effects of any water ingress

Karl you are changing the race when you change bearings and you're not using Milner's are you? Having to keep nipping them up is a sign of not enough pre-load IMO. If it only happened on 1 truck and always the same side I'd have suggested the stub axle was damaged but they can't all be like that!

 

[frank rabbets]

I think the front wheel bearings going out of adjustment is due to a soft washer between the first nut and the outside bearing. If there is any play then movement wears this washer and it gets worse. Many other vehicles I've worked on have a hardened and ground washer for this application.

Frank

 

[Jon Wildsmith]

That washer is a bit soft Frank but I've wondered if it isn't concious design choice? A hardened washer wouldn't wear but the bearing would still be turning on the stub axle and damaging it. On the other hand the rate of wear wouldn't accelerate if the washer was hard ...

 

[frank rabbets]

My washers show significant wear; but to be fair I have never applied a preload but have just taken out all the play apart from a whisker. I can't see why the inner bearing should turn on the axle tube whether preloaded or not unless the lubrication fails. I can see that my axle tube ends are shiny, but not worn, giving witness to the inner bearing slowly creeping round. I've worked on dozens of axles, front and rear and have only seen wear on the axle tube or shaft after the bearing has seized. But yes the soft material washer may be a conscious decision but I don't quite see why. Could it be that if the bearings are preloaded correctly then the washer does not wear and then the assembly takes much longer to go out of adjustment?

Frank

 

[Jon Wildsmith]

I stopped having washer wear problems when I stopped leaving any play at all in the bearing. The wear I used to see was the bearing inner race turning against the thrust washer and I replaced at least one stub axle on my old 80 because in the end the outer bearing wouldn't seat securely. I don't know what the pro's do but mine get done up pretty tight now

 

[karl webster]

Jon,
I always buy my bearings from derby bearings as milner are rubbish or so im told.
Yes i always replace the race as well on my personal trucks as i buy them together.
When i mention other trucks,i mean the ones i buy to sell on. Its vary rare to buy a 80 that hasnt needed the bearings niping up and ive had a fair few. Maybe its just people not servicing them???
Maybe i need to make sure i have this preload sorted next time round. As i mentioned with the 100 though. That has always been looked after and ive done a handfull of miles in it really and ive just had to have a look at the o/s
karl

 

[dave b]

I had a bit of trouble with front bearing on the way to recover karl this is what i found

there was no warning that anything was wrong no steering issues or noise just seized and took me in to the hard shoulder.karl had only tightened the bearing up bout 500 miles before.i even got away with the stub axle even though i had to chiesel off the remains and pull the race off.fitted new bearings complete with washers locking tabs and non chiesled nuts tightened just to take up the play with wheel fitted.

 

[Bat21]

I had a bit of trouble with front bearing on the way to recover karl this is what i found

I think I need to go to SepcSavers

Either that or it's time to junk the N8

 

[dave b]

the floors in perfect focus

 

[frank rabbets]

You might be right Jon. I'll take mine off and check the axle tube and preload the bearings. My 80 had done 30,000 miles when I bought it and there was a lot of play in the FWB's ; enough to force the pistons up into the calipers so that after tight turns the pedal went down a long way. When I rebuilt the axle at 120,000 miles the axle tubes were not worn but I could see where the inner races had been creeping round on the washer. I'll report back.

I've read various methods of preloading the bearings ending with a measurement of 6-12 llbs on the scales on the wheel studs. Should this also be the case AFTER you have put the locknut on as due to play in the threads of the first nut the tightening of the locknut significantly increases the preload on the bearing and therefore it's turning resistance ?

Frank

 

[Jon Wildsmith]

I haven't used the FSM method for so long that I can't remember how it should be done by the book

 

[Brett]

I also tighten my bearings more than the FSM states & they don't work loose anymore.

Been running them tighter for nearly 2 years now with no problems so far.

 

[Chris]

Frank, you run them to the figures that you have described with only the inner nut on. Adding the lock nut to the prescribed torque adds very little to the load on the hub. I have measured both readings. Even if you crank the outer nut up more than you should, the reading doesn't change that much. I tighten mine up quite hard, rotate several times either way and gradually back the nut off until I reach 12 lbs. Rather then have it slack and work UP to 12 lbs. Mine haven't slackened off in the time I have been doing that. I don't crank them up more than that. I think to do a lot more would be to accelerate wear and increase heat build up. I do make sure that all of those bits have plenty of grease between them too.

Chris

 

[ajnabi]

Are the Front hubs supposed to be slightly warm to the touch after about 300 miles on the motorway?
Is this heat being generated from the braking?

IQ

 

[Bat21]

Are the Front hubs supposed to be slightly warm to the touch after about 300 miles on the motorway?
Is this heat being generated from the braking?

IQ

Unless you have been doing a lot of breaking, the heat is unlikely to have been caused by the heat of the discs.

 

[Dave Docwra]

Ajnabi, that sounds fine to me