Strange gearbox problem...

[isuzurover]

I think it must be the selectors or the lever, will pull it down tonight but thought I would ask if the same has happened to anyone?

Yesterday, drove to work, no problem. Later drove to pick up some equipment, 1st and 2nd were a bit stiff (more effort to engage than normal). Drove home, couldn't shift into 1st or 2nd - lever would go over, just not forwards or back.

This morning, 3rd and 4th were stiff first time I tried, then 2nd time, could not get any forward gears - again lever moves across, but not forwards or backwards.

Reverse is fine.

Maybe I can do a "gods must be crazy", and drive around in reverse, sitting on the bonnet? :D

[JDNSW]

Possibly just jammed up with a load of oily dust where the selector shafts come out, but probably more likely either a broken selector spring or loss of one of the retainer plates means there is nothing holding one of the selector shafts into the exact neutral position, and the interlock is then preventing the other selector shafts from moving.

A similar effect could result from a total lack of oil in the box.

John

[isuzurover]

Possibly just jammed up with a load of oily dust where the selector shafts come out, but probably more likely either a broken selector spring or loss of one of the retainer plates means there is nothing holding one of the selector shafts into the exact neutral position, and the interlock is then preventing the other selector shafts from moving.

A similar effect could result from a total lack of oil in the box.

John

Thanks John - what I thought. Definitely oil in the box though - we will see tonight what the culprit is...

[Blknight.aus]

assuming its not selector shafts jaming on the interlocks+detents I have bad news for you...

its the center support bearing/bush gone to lunch.

[isuzurover]

assuming its not selector shafts jaming on the interlocks+detents I have bad news for you...

its the center support bearing/bush gone to lunch.

Centre support bush??? The one that 2nd and 3rd runs on? Hope not, I replaced it with a new one not too long back.

[C H T]

Your problem might be the nut on back end of the main shaft - take the top left hand inspection plate off the top of the transfer case (inline with the gearbox) - you will see the transfer case input gear on the end of the main shaft and the gear retaining nut (usually with a steel lock tab behind it) if the nut is loose it allows the main shaft to move forward and you get the symptons you have described. I had this happen on S111 gearbox years ago

Christopher

[isuzurover]

Your problem might be the nut on back end of the main shaft - take the top left hand inspection plate off the top of the transfer case (inline with the gearbox) - you will see the transfer case input gear on the end of the main shaft and the gear retaining nut (usually with a steel lock tab behind it) if the nut is loose it allows the main shaft to move forward and you get the symptons you have described. I had this happen on S111 gearbox years ago

Christopher

Thanks Chris, but I had that happen to me in the middle of a steel hill at Brookly 4x4 Park once, so I made sure it wouldn't happen ever again - lots of retaining compound. So I doubt that is the problem, and it would affect reverse if that was the case.

Didn't get to pull the top off the box last night - should get it done tonight or over the weekend.

[isuzurover]

Well in case anyone is interested. It was none of the above... The reverse gear bush had started to work its way out - which was stopping the reverse selector from going back to fully to the neutral position, which was putting pressure on the interlocks to stop the other selectors moving.

Bush has been re-peened now, so all is well again.

[Blknight.aus]

ID have never picked that one up...

[JDNSW]

Well in case anyone is interested. It was none of the above... The reverse gear bush had started to work its way out - which was stopping the reverse selector from going back to fully to the neutral position, which was putting pressure on the interlocks to stop the other selectors moving.

Bush has been re-peened now, so all is well again.

Well, that's a new one! But at least it fits in with it being an interlock problem, although not for the usual reasons.

John

[isuzurover]

The same thing happened to a mate's S1 a while back, but he was being silly (reversing up a hill in low range at a 4x4 park), and the bush came out further - locking the box in reverse.