vt v6 commodore clunking when accelerating.

[thebot123]

Hi guys when im drivIng my vt it clunks when changing gears from drive to 3rd. (Not manually chamging the gears just accelerating say up a hill and it has to drop back a gear)
It sounds like the motor but then my mrs thinks its the back end. Either way I just swapped the engine, diff and tranny mounts but it still does it.. could my diff oil be low or is something on my motor on its way out as its done 380,000ks?

shes a well looked after car mind you

Or could it be a new tranny?

 

[kais3r]

Try whether it does the noise from 3 to 2 or 2 to 1, if the noise is just in 4 to 3, then logic would say it's a transmission problem, check fluid level in it with a hot engine and idling, if level is ok then you might have a worn clutch pack or something similar, something only a transmission specialist can properly diagnose.
If it's in all downshifts then it could be something along the tail shaft or diff like worn/cracked rubber couplings or diff mount, if you can get under the car safely, check for slack in the tail shaft by pushing it in all directions or wriggling it around and check for rotational slack by turning it back and forth at different locations.

If all that doesn't show any flaws then take it to get checked at a transmission specialist, won't cost you anything to get a diagnosis.

Doubt it's the engine.

 

[thebot123]

Good on ya champ your a legend..

Either way if it's the trans I'll just shoot to u pull it and rip one out and throw it in they're going for cheap as biscuits down there at the moment.
Haven't got much time to get under it this week but I'll definitely take your advice and have a suss on the weekend it's not an urgent problem just shits me when it makes the noise lol I'm a bit anal with my cars I don't like here grunts, groans or noises only like to hear her purring like a kitten

 

[thebot123]

Also I chucked a brand new diff mount on her mate I've been meaning to. Swap the diff fluid but that didn't happen last weekend unfortunately

So of my tail shaft has any play do you think it'd be worth considering swapping that out soon?

 

[kais3r]

Tail shaft will always have some play, just a matter of how much that matters.

Like I said if you're only getting the issue in a specific gear change, then most likely a transmission issue.
Have you tested it out? It'll help to cut down the problem location.

 

[kais3r]

Also I wouldn't go replacing anything till you know exactly what needs it.
Diagnosing like this isn't effective, you'll need to do the checks or have someone do the more complex stuff like checking trans.

 

[thebot123]

Also I wouldn't go replacing anything till you know exactly what needs it.
Diagnosing like this isn't effective, you'll need to do the checks or have someone do the more complex stuff like checking trans.

No luck yet with getting her on the stands to have a play i leave for work when it's dark and I get home when it's dark so this weekend I'll be sliding under to have as quiz. but I have been bugging round with the gears on the way to work etc and it seems to make the noise going from D to 3rd and from 3rd to 2nd when accelerating up a hill when the revs get to low for that gear and it needs to drop back, in that transition between switching gears the horrid noise comes out and says hello lol. I reckon you may be right the tail shaft could be on its way out. I haven't checked 2nd to 1st yet

If I Cain the **** out of it it won't make the noise it's more when your just cruising. To be honest I took a different route to work today and there was no hills etc and I needed to give her some juice to overtake someone and it still made the same noise when it dropped back, so it's not just hills and decent slopes.

On top of it all my bloody steering rack **** itself I reckon today. driving with no power steering sucks big time can barely make some u turns without accelerating hard and then quickly steering. No biggie though I do have a spare rack.

Will keep this post updated and will try get a video

 

[kais3r]

Ok interesting, the alternate gear test was really to determine if it "was" the transmission only, but from what you've said it could still be any of the above, because there's other areas in the transmission not gear dependent, but start with checking the less complex stuff like you plan to on weekend and go from there.

If you need to do U turns you could just get to 10km/h and put it in neutral and rev the engine to give you more pump power without the extra speed, just let it rev back down before going into drive. Still I don't recommend driving at all without proper power steering as you will wear out your rack & pinion and maybe more pretty fast and it's just dangerous in general.

 

[thebot123]

Ok interesting, the alternate gear test was really to determine if it "was" the transmission only, but from what you've said it could still be any of the above, because there's other areas in the transmission not gear dependent, but start with checking the less complex stuff like you plan to on weekend and go from there.

If you need to do U turns you could just get to 10km/h and put it in neutral and rev the engine to give you more pump power without the extra speed, just let it rev back down before going into drive. Still I don't recommend driving at all without proper power steering as you will wear out your rack & pinion and maybe more pretty fast and it's just dangerous in general.

Your not wrong buddy very unsafe and dangerous, didn't think of the whole neutral and revving excellent idea! Bit busy today on my Saturday but definitely getting under it tomorrow mate like I said I'll get a couple of vids etc.

As for the rack I wasn't aware it could ruin the pinion I think I'll be buying some new tie rod ends today and will be putting my other rack on tomorrow too.

Thanks again advance

Thebot

 

[thebot123]

Alright guys had a suss

I'm my opinion it's the tail shaft it's certainly slowly on its way out, in saying that though the trans is on its way out also.
Getting a tail shaft in the next week or so will let you know if it was in fact that or not, if it's not well the tranny is shitting itself lol

Thanks for all the advice