Worrying Clunk


ok so we had a light fall of snow yesterday, but i decided to lock my hubs 'just in case' their auto hubs, so i just put it in 4hi drove forward about 20ft, stopped, back to 2 wheel drive and left the work car park. just as i got round a corner i heard a sort of whirring sound and as i came to a stop at a set of lights i heard a clunk from the drivers side wheel and when pulling off the whirring had stopped. further down the road the other wheel started whirring so i pulled over and as i came to a stop it clunk again.

Now thinking back i have heard it before on the drivers side when using it in the recent heavy snow.

Im i right in thinking the hubs are way over due a greasing, so have become sticky?. i did intend doing it once the weather had got better. Iv only had her 6 months so have no idea what the previous have / havent done.



"so i just put it in 4hi drove forward about 20ft, stopped, back to 2 wheel drive "

Did you reverse to unlock the hubs, before driving off !!!!, sounds like the front hubs and axle/prop/transfer gears are playing catch up.

I think what was happening was the previously engaged hubs were driving the axle/prop/transfer gears, as you slowed down the faster rotational speed of the axle/prop/transfer gears caused racheting as the hubs tried to relock, the clunk was the hub rengaging/ locking back in under force. NOT good as I had this happened to me ,destroying the internals of one auto hub, replaced with maual hubs.

Edward (ews) '92 Fourtrak 2.8 TDX


no my thinking was to lock them in incase i needed them, i know auto hubs are tempermental at the best of times and thought if i knew they we locked on i wouldnt have to worry about them later. Looks like i'll be taking them apart this weekend to have a look if their damaged. I have no doubt that eventually im going to have to replace them with manual hubs anyway. and from what i hear may not be such a bad thing, or such a hard/costly job. Thanks for the info

Auto Hubs


Auto Hubs designed to lock automaticaly when you select 4WD, you do not need to preselect. When changing to 2WD, you must reverse to unlock the hubs !!!!

Edward (ews) '92 Fourtrak 2.8 TDX

There are no problems with

There are no problems with auto hubs, just owners who do not use them correctly, and fail to maintain them correctly.

Cold weather can affect the hubs, particularly if water and sludge has penetrated them and it freezes. This situation is exaserbated when a vehicle is second hand as the previous owner may have abused them.

Remove the hubs and check for any damage, clean all the grease from the vehicles front wheel bearings and adjust these, pack fully with waterproof marine type grease. Fully clean the hub itself of everything, including greaese, mud, and any corrosion which may have formed. Dry thoroughly and fill with a thick gear oil, allow to soak for an hour to coat all moving components and empty out the oil.

Pack the hub fully with waterproof grease, work it in to all the voids and force it in as much as possible, or use a syringe to pump it in. Overfill the hub with grease and install to the vehicle, remove any surplus grease.
This will give a fully grease packed hub which will prevent water or sludge ingress and insulate it from the cold in extreme weather conditions.
Periodically remove the hubs, depending upon driving or operating conditions, and repack with fresh grease to maintain its waterproof capabilities.
Many operating in extreme operating conditions such as sludge and water find 6 months is ideal, annually for all other operating conditions.

Always remember that a proportion of grease will leak through the front bearing seals over time, this is why they need topping up periodically.


thanks for the info, should hopefully get round to it next weekend weather permitting and such. it appears iv made a mistake in thinking that when going back to 2wd i didnt neccessarily need to reverse. and just assumed they would stay locked. hopefully havent done any damage. but i guess we'll see

thanks again