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With a heavy heart, something broke in the transmission running along at 80 MPH. 5th gear failed with a horrid grinding sound. 1st to 4th still works find but there is a loose object for sure like a 5th gear nut. But you can't put it 5th it grinds bad.

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  • No, overdrive (6th) is inside the case, better support and it is a bigger tougher tranny all around. The issue with the NV4500 is 5th gear is outside the main case. So any slight bearing slack on the

  • We obviously dont agree but based on the pictures and information I've seen so far, I do not believe the pilot walked out of the flywheel on its own.  I think it was drawn out by the wiggling input sh

  • DONT float gears in these transmissions.  This discussion has been hashed out for years and seems to get very heated depending who's defending what position...but no matter, it still stands as a FACT

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7 hours ago, Evan said:

When you hit cruise resume does the computer mash the throttle.

 

Fly by wire not really. It pulls hard not quite a full WOT mash job.

 

13 hours ago, KATOOM said:

It clearly sounds like you need to mellow out your tune

 

Only 1,700 microseconds of wire tap. Most of the magic is the steeper timing curve I'm running pushing the power band up in the 2,500 realm of the tach. Needless to say I still think think the input shaft has a bit of say in this too. This is another reason I've keep the small tires and the tune was very capable of lighting the tires up. 

Its your truck Mike but I'm wondering why you're "upgrading" your clutch and rebuilding the transmission.  You clearly are making too much power for the 4500 given your driving conditions.  Why ask to deal with this again in the future?  It cant be cheap to rebuild that tranny so why not put that money towards something stronger? :think:

Edited by KATOOM

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Need the truck as quickly as possible. Remember Mom requires dialysis every other day. The Cummins is way more efficient that the half ton. Not to mention I need the truck for towing trailers and moving stuff that is just too heavy for the half ton. I use about 600 in fuel per month.

 

As for the clutch between the two I just needed to add $20 for the upgrade. Why not?

 

Personally I think the trans will hold up fine. It was the pilot bearing that created the issue. Since the input shaft goes to the counter shaft it built up some free play and the teeth where just on the tips and the torque did its just and broke them off. This was a reason I went down a tire size to to reduce torque stress. But I never knew the pilot bearing fell out. Lot of unseen problems that contributed to the failure.

 

20190830_143644.jpg

 

We might just have to revisit the fact of the main shaft I broke with Edge Comp and +50 HP injectors. Too much power? Just for Edge Comp and +50 HP injectors to break the main shaft.

 

Image result for mopar1973man main shaft

 

Heck I might as well go back to stock and by a Ford then huh?

Edited by Mopar1973Man

We obviously dont agree but based on the pictures and information I've seen so far, I do not believe the pilot walked out of the flywheel on its own.  I think it was drawn out by the wiggling input shaft from internal problems, especially since it looks like its still intact sitting on the input shaft in one of your previous pictures.

But no matter, lets just hope things hold up for you this time around...

And hope your mom is doing better too... :thumb1:

just my 0.02, but I compleatly agree with @KATOOM. You have another rig to get thru, so put something in you won't break. Or limit yourself on power.. don't go DD on the clutch, step down to a OHD and enjoy 350 rwhp, as that's still plenty of fun in a 7Klb truck. You are using your need of the truck as reasoning to go with the NV4500 again, but you're putting in a setup that hasn't proven as reliable for you current power. Something has to change. 

 

3 hours ago, Mopar1973Man said:

As for the clutch between the two I just needed to add $20 for the upgrade. Why not?

 

 

Because then it's easy to tell yourself that a few more hp won't hurt, and you have the clutch to hold it. You now have solidified that the NV4500 is your weakest link, once that's not cheap or easy to fix... as you well know. Besides that DD suck to drive lots of miles in, it's just not worth it. 

 

I've been reading a bit about NV4500 failures, and what you did to 5th gear is not uncommon at your power levels, and sometimes even lower power than you have. It's not nearly as strong of transmission as I thought it was. 

 

Your small tires are likely also harder on the trans than larger ones, since they break traction so easily. It's not breaking traction that's hard, but as soon as you grab traction again you shock-load the gears and the NV4500 houses the weakest gears in the truck. Just light slip-traction-slip-traction is very hard on gears. Larger tires that don't break traction so easily will not have that effect. 

 

At the end of the day you're just pushing the limits of that transmission. 

 

 

3 hours ago, Mopar1973Man said:

Personally I think the trans will hold up fine.

 

Do you know the definition of Insanity as Albert Einstein said it? 

Edited by AH64ID

39 minutes ago, 98whitelightnin said:

Mike is just too hard on his truck and now his tires are too small!:lmao:

 

I wouldn't say too small, as they work well for his application, but lower traction is just one of several small factors in pushing his trans to a limit.

 

No for how I use my truck they would be too small :lmao:

Edited by AH64ID

No experience with it but I've read of just as many failures of the g56 with higher horsepower as the nv4500.  So I don't know how much of an upgrade that would be.  Plus they are super expensive to fix being that they are made by Mercedes.  And from what I hear the swap isn't exactly a plug and play. 

On 9/5/2019 at 6:07 PM, KATOOM said:

It clearly sounds like you need to mellow out your tune...or put the 4500 aside and get yourself a G56...or both.

 

I don't know how you guys feel about 'German engineering' but when I hear that phrase I cringe and run away from it.  It might have been good in WW2 but has since been surpassed and even lapped.  I have made 2 major mistakes with vehicles...bought a BMW and bought a Mercedes.  Both were tremendous piles of crap.  Those are mistakes I'll never make again. 

Edited by Bullet

2 hours ago, AH64ID said:

 

I've been reading a bit about NV4500 failures, and what you did to 5th gear is not uncommon at your power levels, and sometimes even lower power than you have. It's not nearly as strong of transmission as I thought it was. 

 

 

GAmes  (TDR) went through 12 of 'em. Running a G-56 now.

https://www.turbodieselregister.com/threads/why-does-my-nv4500-always-die.266177/#post-2580990

 

Link on his install:

 

https://www.turbodieselregister.com/threads/221115-Mission-G56-(pictures)?highlight=mission G56

Edited by NIsaacs
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34 minutes ago, NIsaacs said:

I think after that many failures and with the amount of work to swap in a g56...I would've built me a 47 or 48 that would have no problem with the power.  Cool looking swap though. 

49 minutes ago, Bullet said:

I think after that many failures and with the amount of work to swap in a g56...I would've built me a 47 or 48 that would have no problem with the power.  Cool looking swap though. 

 

More people going away from 47/48’s than going to them, especially for towing. 

 

If my 05 had ever needed a trans I would have looked hard at a G56. Not many failures for the sheer number of them on the road, and a higher average lower than any other OE manual trans. 

Just get a 5600 and stick it in there. American made and cheap to work on, if your name is Rockefeller. I got a spare you can have built.:whistle:

Interesting. Is this type of failure prone to happen on the nv5600 as well?

Edited by JAG1

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3 hours ago, Rotket said:

Interesting. Is this type of failure ptone to happen on the nv5600 as well?

 

No, overdrive (6th) is inside the case, better support and it is a bigger tougher tranny all around. The issue with the NV4500 is 5th gear is outside the main case. So any slight bearing slack on the counter shaft or main shaft, one or both 5th gears can tip slightly, the mismatch causes tooth breakage.

 

The 5th gear nut issue is caused by the angle cut gears always forcing the 5th gear against the nut, under torque. The bottom, matching counter shaft gear is only held on by a snap ring, but the angle cut gear is forced toward the case so it don't fall off like the top gear can.

 

The NV4500 weighs 200#, the NV5600 is 360#.

I’ve been under the impression that NV5600’s were not cheap to work on, and fewer of them available. Which is why more people have looked at the G56. Has something changed? 

I myself was being very facetious about the cheap to work on part. A good rebuild is $3k + as long as all hard parts are good.

41 minutes ago, dripley said:

I myself was being very facetious about the cheap to work on part. A good rebuild is $3k + as long as all hard parts are good.

 

??

 

makes more sense. 

Biggest bummer for the current nv4500 is just the plain lack of quality rebuild parts. I am always looking on ebay for oem gears and parts. But I think I will be doing a built G56 as my next project.