Noisy gearbox in all but 4th - Gen1 Pajero

[dan.c]

Hi

Picked up a manual swb gen1 pajero for next to nothing, has a noisy gearbox in all gears but 4th. Originally bought it for the tyres and to just sell on to the wreckers, however it is a bit of a shame as it is quite tidy. Was talking to a guy about the gearbox and he mumbled something about gearbox being easy fix, 4th not being noisy due to 'direct drive', and just needing a bearing, or something along those lines. If someone could explain this and what im looking to replace i would be grateful, never had a gearbox apart before.

Thanks

[slide]

As 4th is a direct drive theres no side thrust from the gears. and no side thrust = less load on bearings.
Could be just bearings, but could also be more like gears teeth worn.

[Weemsy]

gearbox layshaft bearing or bearings will be flogged out

fairly straightforward to fix, but once you pull a gearbox apart you can open an expensive can of worms. synchros, dogs, seals & bearings will all need checking & probably replacing if it already has a couple of bad bearings......

weigh it in at the local scrappy & get a good 2nd hand box would be my 2c

weemsy

[churchill]

^^ sounds right. We had an old van that did that, ended up fixing it but would've been cheaper buying a second hand gearbox.

[Swamped]

I had a gbox that ate a layshaft needle bearing. Exact same symptoms as yours, quiet in 4th. Ran and felt fine but screamed like a banshee. Once opened, a bearing in the middle of the shaft had flogged out the housing.

Go second hand esp if you can confirm reasonable k's.

[dan.c]

Second hand box isnt really an option... was hoping i could just flick a couple bearings in it and away we go. boxs on trademe seem to be around a grand, twice what i payed for the whole truck. I know i can get 1200 for it from a wrecker, so may be better to just get rid of it. It still changes gear fine, and stays in gear, just makes a hell of a noise

[Swamped]

You should be able to get one way cheaper than that. I repaired mine more as a learning experience than anything else and it still whined afterwards and the gbox shat itself 18months later. Among the rest I did new bearings, checked synchros, shimmed properly and this was after having a mate build up the housing and remachine it down. Figured the gears had worn a bit on the piss so the whine remained.

If you want to repair it and are up to pulling it apart it should be relatively easy to find the problem if it is bearing related. decide where to go from there.

Could always fill the gbox with banana skins to hide the whine and flick it off too

[dan.c]

yeah its matter of waiting for one to turn up and having the heap of shit sitting on a mates lawn. so theres a pretty slim chance that shel be sweet after a few bearings? 230km on the clock, doesnt look the the numbers have been clicked back. may pull it out and have a look, if its cheap sweet as, if its a major see ya later

ps. im the guy whos smashed white ute ya pulled out of a gully

[CRAZYBUSTARD]

where you from

[churchill]

If the bearing's been screwed for a while it can wear the gear teeth in a funny way and stuff the mesh meaning they will probably need replacing if you want it to be quiet again.

[Swamped]

O yeah hey Dan totally forgot. Hes from the Waikato.

[89pajero]

If your going to scrap it let me know as I may be keen on a handful of parts if theyre any good.

[dan.c]

thanks for the input guys. i might just pull it apart anyway, good learning experence eh. Is it obvious from looking at the internals that the gears are worn abnormally or is it a put back together and pray kinda job?

Im from hamilton.

Yeap if i get rid of it ill let you know

[Swamped]

I think you might notice a different sheen on the gear teeth as the mesh has changed but I didn't notice anything on mine.
If you end up wanting to part it out one of the guys at the club might be keen too.

[dan.c]

went for a drive today, the noise is not as bad as i remember. will def pull it apart and attempt to fix. however the turbo turbine moves up and down, drips oil and blows a ton of smoke. Gonna have to rig up a 3.1 bighorn turbo up i think. Anyone know of any issues between the two turbos, oil cooled, water cooled etc? havnt had a chance to compare yet.