Front axle - have i killed it?? :-(

For the past few weeks my truck has been making a grinding noise from the front end when the 4wd is engaged. I've suspected its one of the hubs not engaging properly or a knackered half shaft. I took the passenger side hub off (the side i think the noise is coming from) and when driven in 4wd the noise went away, yet when the hub is back on the noise comes back. I havent got the flashing light on the dash indicating a fault with the vacuum, so i think the vacuum is fine, just the hubs thats wrong. But...........

I took it into my local garage today for them to have a look at. They agree with me that there is a noise and also a whine from the transfer box - we both agree that this is the transfer box chain operating as normal. The garage have said that they will strip the front axle for me and have a look at the contents of the diff and the half shafts before deciding on whats best.

Problem is guys, my thinking is its the hub, yet the garage think its likely to be the diff beacuse "with the hub off the diff wont be turning so it wont make a noise". My thinking was all the parts in the axle are turning when in 2wd and when 4wd is engaged so are the hubs, so its likely to be the hubs as it doesnt occur when theyre not engaged. if this is the case, and it is a knackered hub then Im gonna replace them for some manual lockers. Incidentally, im happy for them to split the diff and have a look as it saves me draining the diff myself :-P, plus theyre fitting extended brake lines for me at the same time, so i'll at least know for sure whether its the diff or a hlaf shaft. The garage have said that at worst, they'll source and fit me a second hand front axle if it works out too costly to replace any parts.

Any advice would be gratefully received as to what you guys think it is.

(there wasnt any problem during the snow, no noise and no grinding, and im still getting wind up when its in 4wd and try and turn sharply)

The inside of the axle stays still when in 2wd, unless the hubs are engaged.

Doesn't sound like a hub, but easy way to tell is swap them side for side and see if the noise moves.

I'd start dismantling the axle from the noisy side to see what it is, possibly a CV joint, or the bush bearing in the stub axle, the half shafts have to come out to remove the diff anyway.

(I take it there is plenty of oil in the front axle?)

Yep, I'd doubt its the hub, there's nothing in the hub to make a noise, like facade says, swap them over, it's a two minute job. My money'd be on the CV.
John.

Could well be the diff. Mine made a load of noise and got progressively worse until it was an unbearable noise inside the car when in 4wd. I had about 1/2" play in the pinion bearing, when i removed the diff it was all shot inside and just fell apart. When i drained the diff all the bearings fell out in the oil. If you pull on the front propshaft there will be loads of play if its the pinion bearing.

I'd save a bit of money and drop the diff oil myself rather than getting a garage to do it. Drain it into a shallow pan and you can see if there's anything in the oil. It will cost you about £10-15 for the oil to do the change. Changing the the diff is an easy diy fix too.

Just a quick update - the garage took the front axle part and it was dead When they took the hubs off and removed the half shafts in their terms "you should have seen all the Shi77y water come pouring out on the end of the half shafts, it went on for ages, and as for when we opened the diff up, the sludge, muck and slit in the oil hasnt helped. There was more water in there than oil". Obviously all the bearings needed replacing and there was clear damage to the gears, so i bit the bullet and replaced the whole axle with a second hand one.

CAM suzuki delivered it straight to the garage the day after i ordered it from them and it fitted perfectly (5* service from Cam there - cheers ) and the garage fitted a set of new discs and pads as mine were due for replacement anytime soon. So my truck is back on the road after major organ transplant.

It did have me thinking - CAM Suzuki should start sending out organ donor cards incase your trucks getting written off, that way they know that any trucks they buy in, the previous owners wishes of keeping the jimny sprit alive continues

I have also treated the new axle to a set a of axle breathers and a steering damper from martin, so will be fitting them as soon as they arrive

You should check the rear axle as well. I mean if water and mud enter the front axle so it should for the rear. I hope it didn't.

The rear bearings failed last towards the end of last year. The same garage replaced them and when they did the front axle they checked the rear one again. The rear ones was fine, so chances are the front axle has being filling up gradually. New axle breathers should be delivered from martin these next few days and hopefully that should stop any more water entering the axle. Strangely though, due to work commitments, i haven't been anywhere upto the hubs, let alone wading so i can see how the front axle could have filled with some much water :-S only thing i can think of, is the king pins got replaced two years again, by a "back street" garage and they didnt drain the oil and muck then :-S I dunno :-S All i know now, is its healthy and the current garage i use is a bit more better