NewHilux.net

I have a 2007 hilux manual with 1kd motor which vibrates under load when accelerating through the 1700 to 1900 rev range in 4th and 5th.I have changed the clutch and checked the tailshaft and there was no change.The vehicle was in a rollover which caused one of the conrods to bend when it sucked oil into the combustion chamber. all that was fixed though and I cant find what is wrong and neither can the dealer.It feels like a fuel issue but I am not sure.Anyone have any ideas

Checked engine and gearbox mounts?

what clutch was put into it? did it vibrate before the new clutch was installed?

I have same vibration in that rev range due to new clutch that was fitted.

Have checked engine and gearbox mounts and I put the old clutch back in to see if that fixed the problem and that did not change a thing.It is only under load ie going up hill and will persist while it remains in that rev range but disapear either side

Is it lifted?

Mine had a shudder/vibration caused by suspension lift that used to happen in that rev range and gear combo under load,also coming back into second annoyed it too, has gone away now that it has settled 10mm at the back..

No it is not lifted completely standard

Viper82 wrote:what clutch was put into it? did it vibrate before the new clutch was installed?

I have same vibration in that rev range due to new clutch that was fitted.

Same here - why is that??

Can't speak for others but I had the same problem, if just fitted a 3" exhaust and he vibration had been significantly reduced

any one else having this ?

Gday akibruce,

2 things come to mind.

Have the dowels that locate the clutch to the flywheel been left out? The clutch will end up misaligned to the crank centreline and cause an out of balance.

Has a conrod of vastly different weight been fitted to the engine. You say that it only appears under load! When free revving does the engine seem especially harsh at this particular RPM?

Did this vibration appear immediately after the conrod replacement?

My 2 cents worth. I apologise for the following ranting!!
It surprises me again and again that dealerships will just replace one conrod without checking to see if the weight is even close to the original. When engines are mass produced originally, conrods are graded by weight. They are normally within 5 - 10 grams and this is considered acceptable by most car companies. I have purchased individual Toyota diesel conrods (mainly 3L and 1HZ engines) and had them vary by more than 50 grams from the original, often requiring swapping for another new conrod to get it closer, so the set can be individually balanced. No single conrod should ever be replaced without match balancing it (if it is heavier) or match balancing the remainder of the rods (if the new rod is lighter).

Not checking the weight of a new conrod is a gamble. 9 times out of 10 the engine will not vibrate. You may be that other 10%.

I hope that I am wrong and you find something simple.

Some additional advice to anyone who is having a diesel engine rebuilt. Pay the extra to have the whole rotating assembly balanced and you will find just how smooth a diesel engine can be (and just how poorly balanced they often are from the factory).

Whenever a flywheel is remachined and a new clutch fitted these 2 items should always also be rebalanced. The shop i work out of gets several clutch/flywheels a week from people chasing vibrations.

By the way i should have introduced my self as a Sydney based engine builder specialising in engine development for circuit racing and rallying. I live and breathe engines. If anyone wants to PM me, I am more than happy to give out my mobile number for people who are having engine related problems.

Regards
Chris

On top of what Chis has said, just had dealings with a Nissan had one piston to replace due to the usual flame down the side, four attempts with Nissan to get a new one that would come any-ware near the same for weight. Had to replace all four with aftermarket. Very easy thing to go wrong when trying to keep costs down.

the dowels are in and there is no vibration when free running at any point just in 5th and 4th underload.I have swapped wheels and exhausts with a mates to check if that was an issue.I believe it was a balance problem within the motor it would show up when free running probably a little down the rev range but it would at least show up.Thanks for your input Chris it is greatly appreciated

You say it feels like a fuel issue? Does it hesitate when this vibration is occurring?
Have you thought about the actual transmission being damaged?

Im pretty sure these engines have a counter balance shaft. maybe this shaft wasn't set properly when the head was put back on

The transmission is my next thing to look at.I dont think it is the counter balance shafts as this would cause a vibration when the engine is free running and in all gears

Clutch..........4th and 5th, 1700 - 1900 rpm and under load.

Has to be surely. After all everyone went through with the clutch industries HD one and these being the exact same symptoms I can't see it being anything else.

I had a clutch industries pressure plate and clutch plate in.However I pulled the pressure plate off and put the old one back on as I thought there can be no problem with the plate.

Well it wasn't the pressure plate that was the problem it was the clutch plate. So if your still running the original clutch plate ide say that is your problem still.

I should have posted more information - my bad.

Had a heavy duty clutch fitted as it just wasn't keeping up with the chipped D4D.

Vibration is in all gears at around 1700 - 2000rpm but most noticable in the higher gears.

Had no other work done at that time.

Seriously is anyone changing conrods on the unbreakable?

Just bringing up an old thread how did u go with this? my 2006 turbo diesel Hilux is doing the exact same thing

Mine does as well, same rev range and mostly more noticeable in the higher gears. Free revving shows no vibration.
I've long believed it to be the clutch however the vibration is only an annoyance so I have far better things to spend my money on in the meantime.