Freewheel hub being honed out by misaligned side axle shaft

[Ryperd]

So I was replacing the front right freewheel hub for the second time (after installing a cheap Chinese hub as a temporary measure), and had a nasty surprise. The original hub had a brass bush that was worn out, but this one just had the solid hub body without the bush. After driving with it for only about 900km, it had been completely honed out by the inner gear (by inner gear I mean the gear that slides onto the splines on the side axle shaft - which you can see in the photo below), so that it looked basically the same as the previous hub (notice the large gap at the top):


You can get an idea of how it's honed out from this short video:
https://www.youtube.com/watch?v=uzVg0DEmQVU" onclick="window.open(this.href);return false;

If you look at the side axle shaft sticking out here, you will notice how it's pushed to the back:


The replacement freewheel hub did not go on very easily, and I had to massage it with a rubber mallet to get it onto the studs (studs removed in the photo). I suspect that the axle is bent, and is forcing the inner gear into the hub body or bush. As the wheel rotates the gear is basically honing out the hub body or bush. Although the freewheel hub in the picture is a cheap one that I wouldn't recommend to anyone, I think if I put another more expensive one on, the same thing will probably happen. If it's made of stronger material, it could potentially do some damage to the stub axle itself.

I'm pretty sure this means that the axle is bent, but I'm happy to hear from anyone who has a better or different explanation for why this is happening. The challenge is that we are planning a trip to Zambia and Malawi in 2 weeks time (using this vehicle of course), so I don't have much time to sort this out. My first plan is to take the vehicle up to Ronald at 4x4traction in Polokwane, but I don't know if he'd be able to sort out the axle in time.

Some questions:

1) How big a deal is it to straighten a bent axle? The bearings have recently been redone, so it should just be a case of taking off the steering knuckles to get to the side axle shafts. Not trivial, but hopefully not too time-consuming or expensive. Any recommendations of a place to do it in Pretoria?

2) If it's not feasible to straighten the axle before we go, can we use the original freewheel hub without the bush? I'm pretty sure I used the vehicle in 4wd without realising that the freewheel hub was not in a good state, and didn't notice anything wrong. What damage could we be doing to the axle shaft or diff if we use it like that?

3) Would there be any danger in removing the inner gear and essentially disabling the hub completely? The freewheel hub then is basically only serving as a cover, and we'd have to use the vehicle in 2wd only.

Any other suggestions?

[LouisZ]

Phone Tokay 4x4 in Montana at 012 5489979. Ask for the L/C 75 Free wheel hub. Its the same as the Hilux SFA.

[The Legend]

Rudi if the axle is bend the chance is good the axle/diff casing might also be bend.Have it check as well.Did your axle not get damage with the previous accident you have with your bakkie?

[Ryperd]

Dawie, yes, I think it happened with the accident. Sorry, I think the axle is still straight, it's the axle casing that I think is bent. If I turn the front propshaft by hand, the side axle shaft does not wobble.

[CasKru]

Just thinking out loud here but when someone serviced the front wheel assembly, did they replace the shims on the kingpins exactly as they were previously as this greatly influences the alignment of the shaft.

[Ryperd]

Phone Tokay 4x4 in Montana at 012 5489979. Ask for the L/C 75 Free wheel hub. Its the same as the Hilux SFA.

Thanks Louis. I actually have a replacement hub already, but I think it will get eaten out like the other two hubs (the original one and the cheap Chinese one). I first want to get that side axle rotating true so that it's not pushing on the sides of the freewheel hub.

[Ryperd]

Just thinking out loud here but when someone serviced the front wheel assembly, did they replace the shims on the kingpins exactly as they were previously as this greatly influences the alignment of the shaft.

Cassie, if you are referring to the shims at the top and bottom of the steering knuckles, I did replace them exactly the same when I redid my bearings in December. It might be that they were out of balance from someone who worked on them previously, but it didn't come out when I had the alignment done recently.

[Mud Dog]

Bent banjo housing - almost 100% certain of it. It will do the same with any new free-wheel hub that you fit. You will have to have it sorted first.

If you absolutely have to go on a long trip before you can get it sorted, then leave the hubs engaged. It will use more fuel and not so good for the front diff, but at least it won't wear the new hub (the drive axle will turn with the hub).

[Ryperd]

Thanks Andy. When we overhauled the front axle, Louis realised that there is some kind of permanent front diff lock mechanism. If the one side axle shaft is rotated, the other one rotates in the same direction, and they can't be turned independently. Because of that, leaving the hubs engaged would probably damage the diff.

I spoke to Ronald from 4x4 Traction this afternoon, and he says he had a vehicle there with a similar issue recently, and he can sort it out for me (sounds like it was indeed bent banjo housing). He has a spare driver coming down this way in the next couple of days. He'll take it back up to Polokwane and hopefully will have it sorted out in time. It will be good to have someone take a look at that diff centre portion in any case, and figure out what's locking it. Having a locker of sorts will be handy in Zambia, but if it's damaged somehow, I'd rather know that now.

As a separate note, 4x4 Traction can overhaul the inner parts of the freewheel hub, so if anyone has a good AISIN that just needs a new bush or replacement gears, I'd highly recommend sending it to them to overhaul. I've been very impressed with their knowledge and service in general.

[Mud Dog]

Hmmmm ..... it might have an auto locker of sorts fitted (maybe True Trac). In that case you cannot do as I suggested as a desperate measure for any lengthy distances. Looks like your only option is to have it sorted before you go - the best option anyway.

[Ryperd]

Just a followup on this. Ronald and his team did a great job to sort out my axle in not a lot of time! The axle housing was too bent to fix, but they had an assembled axle that they were willing to disassemble for me under the circumstances. They added gussets for extra strength, so Ryperd probably has the strongest front axle of any SFA on the roads now! It was a lot of money that wasn't budgeted, but peace of mind is worth it. I'd recommend 4x4 Traction for any drive-train, suspension or custom work.

[The Legend]

Foto,s of the new axle??

[Ryperd]

Sorry Dawie, here you go!

[The Legend]

Sorry Dawie, here you go!

Eisch that looks great.

[Mud Dog]

Nice neat reinforcement!

You can still bend it though if you klap something hard enough, so keep it clear of rocks and anthills .....

[Ryperd]

You can still bend it though if you klap something hard enough, so keep it clear of rocks and anthills .....

Thanks Andy... my plan is to never need the reinforcement, but when the going gets tough it's good to know that it's there.