ZF5 Help!! Neutral Grinds

[Pino2234]

I finally bled the clutch and drove my 85 F350 dually for the first time.

I have a 1991 7.3 and ZF5 Combo I put in this truck last year and finished it today. I started and a few days ago and everything sounded fine.

I bled the clutch today and put it in first and drove it for the first time today and when I put it in nuetral it started a loud grinding sound.

I drove it again and it makes that noise in the gear too but inconsistently. I put the transfer case in neutral so it wouldn't move and went through the gears. (Also pushing in the clutch stops the grinding) I went through the gears without pushing the clutch and halfway in each gear it stops but 1st still makes the noise. 2nd sounds a little quieter but still there. 3rd is the same as 2nd and 4th, 5th & R all have a skip grind sound. Like the grinding gets more violent but not at frequent.

I emptied the trans and took off all the plates and can't find anything.

Every gear works and I did the lucky mod to the fly wheel

 

[Diesel_brad]

Sounds like the bearings for the input shaft are bad. that is the only thing that should be spining in neutral

 

[alienturtle]

Every gear works and I did the lucky mod to the fly wheel

does that mean you welded the flywheel together and is acting like a solid flywheel? If the lucky mod is not what i think it is then disregard what i just said

if so then you are experiencing gear roll over noise and is an outcome of a "solid flywheel"l..It wont go away unless you go back to a dual mass flywheel.

 

[bike-maker]

I run the lucky mod in mine; sounds like rollover noise is what you are experiencing. Also sounds like the clutch isn't quite bled yet, so it's still dragging a bit.
Mine has the rollover noise intermittently. When you roll up to a stop and let the clutch out, sometimes it makes no noise, and other times it's really loud, sometimes it's quiet for a few seconds, then all of a sudden starts making noise. It goes away temporarily if you blip the throttle. If you lug the motor very much, it will rattle as well. Biggest giveaway is you don't hear it at all if the clutch is pushed in.

 

[alienturtle]

Biggest giveaway is you don't hear it at all if the clutch is pushed in.

ok so the lucky mod is a solid flywheel then..i wasnt sure..and that is exactly what i thought as well

 

[Pino2234]

Sounds like the bearings for the input shaft are bad. that is the only thing that should be spining in neutral

It is pretty bad in 5th too. I took the top loader off and started the motor in 5th (tcase in N) every time it grinds it pushes the shift fork forward.

does that mean you welded the flywheel together and is acting like a solid flywheel? *If the lucky mod is not what i think it is then disregard what i just said

if so then you are experiencing gear roll over noise and is an outcome of a "solid flywheel"l..It wont go away unless you go back to a dual mass flywheel.

The lucky mod is in the tech section.*

Gear rollover? But it didn't do it all the times I started the motor before I had the clutch bled. I started it to check the cooling system, turbo and oil leaks. A week later I bled the clutch(today).

I run the lucky mod in mine; sounds like rollover noise is what you are experiencing. Also sounds like the clutch isn't quite bled yet, so it's still dragging a bit.*
Mine has the rollover noise intermittently. When you roll up to a stop and let the clutch out, sometimes it makes no noise, and other times it's really loud, sometimes it's quiet for a few seconds, then all of a sudden starts making noise. It goes away temporarily if you blip the throttle. If you lug the motor very much, it will rattle as well. Biggest giveaway is you don't hear it at all if the clutch is pushed in.

Yea when I push the clutch in everything goes away but if the clutch wasn't bled I wouldn't be able to get it into gear right? And this noise is happening when the clutch pedal is released so it should have nothing to do with the hydraulics.

 

[Goofyexponent]

When you did the lucky mod, did you use a sprung clutch disc?

How much fluid is in the trans? Sometimes overfilling it with a full gallon will eliminate a lot of the rollover noise. I personally have NO noise, but I am also running an un modded DMF....wonder how long THAT will last!!!

 

[Pino2234]

When you did the lucky mod, did you use a sprung clutch disc?

How much fluid is in the trans? Sometimes overfilling it with a full gallon will eliminate a lot of the rollover noise. I personally have NO noise, but I am also running an un modded DMF....wonder how long THAT will last!!!

I did the mod last year and I made sure my new clutch disc had springs in it. I also did what the tech article said and overfilled (2 gals) with 30wt.

 

[bike-maker]

Mine seems to be dependant on engine RPM, and doesn't change in different gears. Like I said, if you lug it pretty good (like in parking lots) it will growl pretty good.
Mine has 2 gallons of 30wt in it also, filled through the shifter hole. Bleeding the clutches on these things is one of the biggest PIA's there is. Most people (myself included) can't get them bled very well until they just drive the truck for a while. I bled mine about 20 times until finally I got it jammed into 5th gear, let it sit for a few seconds, then jammed it into 4th, then 3rd, etc. until I finally got it down into 1st. It drug like hell at first, but after a hand full of miles, it started working just fine. Been working great ever since.
The clutch disc was a sprung one right? If it was solid, it will break the center out of it.

 

[Pino2234]

Just keeping everyone updated the lucky mod flywheel seemed to be whobbling so I pulled the trans on Friday and ordered the LUK solid mass flywheel conversion for $350.

 

[Pino2234]

The LUK flywheel and clutch came in. After I installed it there was no grinding. The single mass conversion I made was really unbalanced. So for $350 you can get a single mass conversion that doesnt put strain on your input shaft.

 

[Fordsandguns]

Did you bolt it together like the original Lucky mod or did you weld it? Just curious why it would wobble if it was bolted together.

 

[Pino2234]

Yea I bolted it with grade 8 bolts and lock tite. I don't know either but for the headache $350 was worth it.

 

[towtruckdave]

The LUK flywheel and clutch came in. After I installed it there was no grinding. The single mass conversion I made was really unbalanced. So for $350 you can get a single mass conversion that doesnt put strain on your input shaft.

Thanks for following up on your problem. I am glad you found your issue.