Rattling Sound in all gears but 4th

[damo667]

Hey Guys why does your truck always break when your the furthest away from home?

I was driving up the west coast and about 50K before Greymouth started to hear a clicking sound coming from the engine or gear box,

Checked Oil in Gearbox and Transfer case.. seemed fine.. Then started to think it might be a ticking from the exhaust.

I carried on and it got louder as I thought it would if it was a hole in exhaust..

When I got to Grey and slowed down I noticed the ticking/clicking was quite loud at low revs so that made me question the exhaust theory..

I then noticed that it makes sound in ever gear but 4th.. its dead silent...



Does anyone have any ideas? What are my chances of getting back to QT in 4th

Cheers in advance..

[geeves]

so noisy in 1 2 3 5 r?
Check your driveshaft ujoints first Also check the driveshaft centre bearing
Check for rocks between body chassis exhaust and brakes
Take a sample of gearbox oil after a short run and after its sat for a while looking for water or shiney bits
All of the below is a guess with no chance of warrentee or comeback
Contaminated gearbox drain refill hope for the best try and drive back
Either rear ujoint Take the driveshaft out split it and reinstall the front half Select 4wd to drive home in front wheel drive (been there done that but not 500km)
Front u joint or center bearing is an issue. Your gearbox has a spline output that seals against the driveshaft Take it off and it will pump the oil out. If you can figure out a seal go for it as above but when I tried it dropped half a litre of oil in 500 metres.
Of course if you head for Haast there is only one decent hill and its not far from home by then

[damo667]

Cheers Geeves
Yes 1235 and I think reverse but I'll confirm that tomorrow
I'll have a good look at the Ujoints in the morning, didn't get a chance tonight,

Weird how it doesn't do it in 4th?

[turnturn]

Isn't 4th gear 1:1? As in the only gear where the input shaft is locked directly to the main/output shaft? Not exactly sure how this helps you in your situation, but something to consider.
What in the gearbox, when all other gears are engaged, could make a clicking sound?
Is 4th gear the only one that doesn't involve the layshaft under load?
Does the noise stay constant with road speed? Or engine speed (gearbox input shaft)?

[isuzurob]

turn turn you are correct, i would say it has broken a tooth off the gearset on the lay shaft in the gearbox, it should be fine to drive just try not to put it under to much load in 1235 gears

[damo667]

It is constant with the engine speed turn turn..
the truck still running fine other then the noise,The noise is getting louder though.
So if that is the case hopefully would get me home and gearbox rebuild needed soon as..

[damo667]

800 k's after the noise started ad I've got it home drove most of that at 80-90 in 4th gear

Before i set off home I replaced to oil in the gearbox and transfer case and there was a bit of metal and even a bit of water but having said that I've seen alot worse.
Cant see and signs of wear to u joints or central bearing

The noise got louder and louder to begin with but then reached a point where it stayed constant. Its kinda the same sound as a really bad CV Joint the way it clicks..

It is present in all gears but 4th still and you can even seem to hear it slightly in neutral until you press the clutch. It is present in 2WD, 4WD and 4WD low..

It made it all that way without any 'crunching' but i parked it in my driveway which is quite steep and when I went to move it to bring in my other car it sounds way worse and sounded like its slipping from the extra load of a hill start. I had to put it in Low 4th to move it

Suppose I'd better drop the gearbox out at the weekend and have a look. Are part replaceable in the gearbox or I'm I looking at finding a second had box?

Cheers for your help guys

[mattmannz]

Parts are replaceable. These also destroy the input shaft bearings.

Depending on what you want to spend it might be better to get a second hand box if you can find one that has been looked after that has less than 200ks on it

[isuzurob]

there is a guy in chch with 2 gearboxes out of 2.8 bighorns they are on trademe

[damo667]

Cheers guys I'll have look at the weekend and see what the damage is and work out a plan.. is there anything I should replace on the the new box before I fit it if I go for that option?