Noise on gear change

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Hi, I now have another problem? to add to the increasing list any ideas? When I change gear (changing up) as I let the clutch up there is a noise the best way I can describe it is like there is some one underneath tapping metal with a metal spoon!! it has also made this noise on occasions when I take my foot off the accelerater if going at a higher speed. I had 2 now UJs fitted on the back a few months ago and that solved the problem for a couple of weeks, I have been told that the front ones are OK with no play, however if grease is pumped in there it does stop the noise for a few days, so could it be the Ujs even though they appear OK or could it be something in the gear box, the noise sounds like it is coming from under the gear stick or in front of it. Any sugestions??

Thrust bearing springs to

Thrust bearing springs to mind, check its adjustment on the cable first to ensure this is OK. On the side of the bellhousing is a fork for engaging the clutch, remove the rubber surrounding it and you can see it with a torch, and listen.

Other suggestions would be the U/J's or the propshaft splines worn, do you also grease the splines as these are often forgotten.They have a hole under the spider where the grease comes out when greased fully, this lets dirt and water in also, and worsens this problem.

Check any underbody plates, these may include those heat shields around the exhaust if they are still fitted as these corrode and snap.

Check the silencer boxes by hitting them with your fist, internal corrosion causes rusty lumps to build up on the bottom of the silencer casing.

noisy gear change

Hi thanks for your reply, I will ask my dad to check the splines. As it only makes the noise when its moving could it still be the thrust bearing? as I read somewhere that the thrust bearing will make a noise when stationary too and my fourtrak doesn't. many thanks.

Yes it can, it is the

Yes it can, it is the vibration of the gearbox input shaft which generally causes it. Modern vehicles have their thrust bearings in contact with the pressure plate at all times, although it only just touches with the clutch released it keeps it turning and takes out any slack.

Many people do grease the prop shaft u/j's, but not the splines as it takes a large amount of grease, and often the nipple is smashed off. This often means people are not aware that they can be greased so do not do them.

If in 2wd (as you should be

If in 2wd (as you should be on the road) with the free wheeling hubs unlocked (if they are manual) you should be able to discount front drive train, as it should be isolated, and stationary. When the rear prop was off to fit new UJ's, was the rear diff input flange checked for play? This would probably produce a more heavy metel noise if out of wack, but worth checking.
Other than that, if there is play in the drive chain (bar in mind that there is always a small amount) then finding where the play is may help diagnose the issue.
Jack one rear wheel off the ground (with front wheels chocked). Put it in 1st of reverse gear. Leave transfure in 2wd. Hand break off. Now if one person turns the lifted wheel as far ase they can in one direction, then back to other way, and keep repeating this. A second persone can look under the car to see where any extra play may be occering. Also they can have a good listen for tell tail knocks.
Under normal conditions the wheel will turn about an inch or two at most.

Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.