Is it normal to get clanking noise from driveline when releaseing clutch

[Grizzly]

My neighbor has a 2006 CTD DRW, 6 speed G56, 4WD. Every time he changes gears, he get a clanking noise from the drive line, which he says come from the transfer case to the front axle. The two dealers and independent transmission shops he has taken it to say it's normal. My 05 doesn't do it, my son's 04. 5 doesn't do it and my 95 never did it. He said that when he changes gears at 1500 RPM and is very easy with the clutch, he can avoid the noise, but when he pulls his 5th wheel, he can't avoid it.

 

[roperteacher]

My 06 will do this if I am pulling my large horse trailer and I am in first gear going down a fairly steep grade. If I push in the clutch and go to 2nd gear while still on the incline it will do it. Thats the only time however. I figured it was just the pressure from the load. . On the flats it does not do it. .

 

[DBoggs]

I'm having that exact same issue in my Kenworth. According to the shop I deal with for it, it is either a U-joint, carrier bearing or rear end.



There is excess slack in the driveline someplace and that is whats causing the clunk. He can ease into it and take up that slack slowly and not get the clunk, but when towing you can't ease into it that slowly or you lose to much speed.



A certain amount of freeplay is normal but if it is causing a pronounced clunk, then in my opinion it is too much.



The only time my 06 clunks is if I don't come to a complete stop before I shift from reverse to drive or vice versa.



Duane

 

[rbattelle]

It's probably a bad rear driveshaft universal. Having said that, there is slop in the driveline normally, and even with brand new universals it is possible to make a sort of "thud" sound if you work the clutch just right.

But a loud clunk is almost certainly a universal joint.

Ryan

 

[BHolm]

Grizzly, Not sure if that is what you meant ot type but it says, he thinks it is coming from the t-case to the front axle. Unless it is in 4wd, there is no tension at all on the front driveshaft. It spins freely until you engage 4wd. I seriously doubt that is really where the noise is coming from.

That said, I get some rattling around of driveline parts when shifting, not bad and I accept that it is probably normal. There is a lot of driveshaft back there on the lwb trucks, and a center bearing, making for more places to generate noise. I am getting the whole driveshaft and center bearing assembly replaced, hopefully this week still, and I will report back and let you know if it helps with some of the noises I hear.

Changing gears at 1500 rpm, especially if towing, is something I would avoid. You are lugging the engine by running hard below the torque peak. I would run it up to at least 2500 with a load on before shifitng.

 

[jelag]

I think Duane's on track here..... I've had the problem with our 04, 3500 dually pulling our 22K lb trailer... We tugged and pulled on the drive line and it felt good..... we pulled it down and found 2 u-joints bad..... these drive lines are a nice piece of work... . even with a small pry bar I didn't see the movement in the joint yet when it was apart it was very apparent to me that they were bad. .

You need to take it apart to check it out in my opinion.....

 

[Grizzly]

Grizzly, Not sure if that is what you meant ot type but it says, he thinks it is coming from the t-case to the front axle. Unless it is in 4wd, there is no tension at all on the front driveshaft. It spins freely until you engage 4wd. I seriously doubt that is really where the noise is coming from.



That said, I get some rattling around of driveline parts when shifting, not bad and I accept that it is probably normal. There is a lot of driveshaft back there on the lwb trucks, and a center bearing, making for more places to generate noise. I am getting the whole driveshaft and center bearing assembly replaced, hopefully this week still, and I will report back and let you know if it helps with some of the noises I hear.



Changing gears at 1500 rpm, especially if towing, is something I would avoid. You are lugging the engine by running hard below the torque peak. I would run it up to at least 2500 with a load on before shifitng.

I asked him the same question and I did tell him that the 4WD is spinning free and shouldn't make any noise unless it was engaged. I agree with you and think the noise it's coming from somewhere forward of the differential.



I'll see him today and pass all this on. Thank you everyone.

 

[AWay]

I have my 06 at the dealer know for them to check this same problem out. Mine is only 2wd, but if you don't time your shift just right, it will clank when you disengage the clutch. Slower speeds are the worse. I'll let you know what they found. Just called and they gotta keep it over night.

 

[y-knot]

If it was your truck, would you think that too be NORMAL??

 

[BHolm]

If it was your truck, would you think that too be NORMAL??

Well that depends. None of us are there to hear/feel the clunk in this guys truck. I don't think it is reasonable to expect a truck like this to be perfectly silent in operation, do you? On a six speed truck with a load on there is going to be some axle wind up. Releasing the pressure by disengaging the clutch is going to suddenly cause the pinion angle to change. Would it surprise you if that made a slight clunk? I don't think it should.



If the pokey dealer ever gets my new driveline in, I should be able to offer a little insight between 70k hard miles on a driveline, and a fresh set of joints and center bearing, not to mention likely tighter slip joints.



Those fairly new to these trucks may not have a good reference point for "normal". I am on my sixth third gen, I feel like I have a pretty good handle on what normal is for these trucks, his doesn't sound that dramatic, but like I said, I'm not there either. When an independant agrees with the dealers assesment, it might just be so. If it is under warranty still, and you gripe correctly, they will probably replace the whole driveshaft. If it bothers him, why not go for it and see if the concern was justified?

 

[abrankod]

My 07 has done this from day 1. I think its just the dual mass flywheel clunking as tension is suddenly released from the driveline as you clutch.

It has taught me to be a better driver, shifting on the moment the driveline goes slack from releasing the throttle. Its a more proper shift and minimizes stress on the whole driveline. If you pay attention to how big trucks with non synchro'd gearboxes shift, you'll notice that they shift the same way...

-Dan

 

[Grizzly]

Could this be G56 issue, because my NV5600 nor my son's NV5600 does it. I have no idea what the transmission has to do with it, but in reviewing these posts, it seems like only some trucks with the G56 have this problem.

 

[jgillott]

My 07 has done this from day 1. I think its just the dual mass flywheel clunking as tension is suddenly released from the driveline as you clutch.





-Dan

Could this be G56 issue, because my NV5600 nor my son's NV5600 does it. I have no idea what the transmission has to do with it, but in reviewing these posts, it seems like only some trucks with the G56 have this problem.

My '07 has done it also since I brought it home. The sound seems to come from the clutch area in mine. I'm not sure if that is the source of the noise, but it is where I notice it.

 

[JWHays]

My '99 did the same thing...



... John

 

[AKaiser]

Mine clunks alot in low gears at slower speeds. My gasser did too.

 

[AKaiser]

Mine clunks alot in low gears at slower speeds. My gasser did too.

As of today, I have had the dealer replace the rear driveshaft u-joints. The tail end joint was going out,and only within the last month (I've been under it). It only started to make clanging noises a couple of days ago. The dealer called and said they put both U-joints in it. $100 bill and that was the warranty deductible. I'm curious to see the cost sheet on this. If I had the equipment, time, and a shop, probably could've done it for half that, whatever parts cost. I'm also out $30 for gas ($3. 18/gal) and whatever the rental fee was.

 

[Wdoucet]

My 07 has done this from day 1. I think its just the dual mass flywheel clunking as tension is suddenly released from the driveline as you clutch.



It has taught me to be a better driver, shifting on the moment the driveline goes slack from releasing the throttle. Its a more proper shift and minimizes stress on the whole driveline. If you pay attention to how big trucks with non synchro'd gearboxes shift, you'll notice that they shift the same way...



-Dan

Mine also clunked from day one, tried shifting at different speeds (probably better syncronized) and it all goes away (except for once in a while when I miss a shift).

 

[Grizzly]

Mine also clunked from day one, tried shifting at different speeds (probably better syncronized) and it all goes away (except for once in a while when I miss a shift).

I have looked at all these posts and so far it seems to happen only to the trucks equipped with the G56 transmission, with a couple of exceptions. That is the 05. 5, 06 and 07, all with the G56. Why is that?

 

[msperos]

Mine will clunk if I'm pulling a heavy load and put the clutch in while on the power. I have always chalked it up to energy stored in the dual mass flywheel. Just my . 2 cents

 

[AKaiser]

I still have a clunk in the driveline; slack in the gears, I suppose.