Clunk/thud In Transmission

[duffsparky2]

Hi All,

I originally posted this in the Toyota Family section back in September because there does not appear to be a section in the forums for my vehicle but got no replies. So I've re-posted it in the Hilux forum because I think my vehicle and Hilux transmissions are similar/same.

I have a 1998 Hiace Powervan 2.4D that has developed a heavy clunk/thud noise whenever I release the clutch pedal, the problem can also be felt through the seat, pedals and floor. It happens when changing up through the gears and is noticeable at any driving style except very gentle. At first I thought it might be a propshaft joint but I seem to remember (from the dim and distant past) that a worn prop joint also causes excess vibration and there is none out of the ordinary.

The problem is also noticeable if I press and release the throttle pedal repeatedly several times in quick succession, however, I've only done this a couple of times just to prove it happens. The van has done about 87K miles so its hardly run in (tongue-in-cheek). The problem only appears to have started fairly recently although having said that the van hasn't been used very much in the last 5 years or so (perhaps a couple of times a month doing 5000 or 6000 miles in that time).

Any help would be much appreciated.

Cheers.

[Max34]

Total guess does your van have a double mass fly wheel?

[duffsparky2]

I wouldn't have a clue about the flywheel but I think the problem is not the diff itself but a worn rubber(?) bush in the diff stabilizer arm where it is secured to the chassic. Transmission repair man said diff is worn but not excessively. I'll change the bush/arm and see if that cures the issue. Thanks for the reply.

[Andybruv]

I experienced a very similar problem tonight with my 2001 3 litre diesel. Perhaps the very same problem.

it starting with a slight knocking.  Then as I was driving I tried dumping the clutch, not to excess.  It normally would have been fine,  but it very quickly got to a severe clunking/ thud I coukd feel through the floor / pedals.  I felt I had to keep the revs high just so I could make it home.  Felt like the prop was going to fall off.

 I’ll post again when I find the cause