Upgrading the NV5600 for faster shifting.

bigbore050

The Original Rookie
Joined
Jun 22, 2010
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147
Well I broke my NV5600 again last week and I have been searching for ways to improve this transmisions shifting. I belive I broke the blockers again but wont know untill we get the tansmision apart.

I am teaming up with my rebuilder to redesign the 2-3, 3-4, and 5-6 blockers. We are hoping to greatly reduce the time between shifts and inprove the life of the blockers. I hope to start the machine work later this week and hope to have a transmision togeather for testing in a couple of weeks.

Would there still be interest in this transmision upgrade or is everyone giving in and switching to the G56s?
 
my opinion......


thats one huge waste of time and money

with these big HD trannies, its just never going to be as fast as an auto
 
Half the problem is having enough clutch to hold the big power and still shift.

Maybe the 500hp and less single disk trucks might see an advantage, not the 700+ double disk.
 
It might not be faster than an auto in the long run but i do think they can go faster then has been done in the past. I think if you get someone to build the right clutch and 5 speed combo, high tens would be possible.
Mind you that will be in a very light 4wd single cab with a 4 link. It would have to be all out to get there. Not sayin it will be cheap either.
 
Half the problem is having enough clutch to hold the big power and still shift.

Maybe the 500hp and less single disk trucks might see an advantage, not the 700+ double disk.

I see the clutch as one of the biggest issues also.
 
Yes I know there will never be as fast as a auto but this is more for the die hards who dont want a auto. The cost will be small I hope. Mostly just moding whats there but 1 part will need to be built form scratch. I see the cost of tearing down the transmision for the new blockers to cost more than the blockers themselfs.

I agree that the clutch is a big factor also. I belive its just the extra mass that the blockers have to make up for. Agree or is there more to it than I see?

Im not a Trans guy. Im just the guy who can make all the new parts and always looking to make something better.
 
It might not be faster than an auto in the long run but i do think they can go faster then has been done in the past. I think if you get someone to build the right clutch and 5 speed combo, high tens would be possible.
Mind you that will be in a very light 4wd single cab with a 4 link. It would have to be all out to get there. Not sayin it will be cheap either.

the power it takes to run 10's is gonna shatter a 5 or 6 speed......
 
And trying to drag race a 5 or 6 speed launching in 3rd gear and shifting twice isnt going to have any shockload?

1200hp boosted launch in 3rd gear 4wd = little pieces everywhere
 
And trying to drag race a 5 or 6 speed launching in 3rd gear and shifting twice isnt going to have any shockload?

1200hp boosted launch in 3rd gear 4wd = little pieces everywhere

I'm in 6th with only 600hp years ago. :) and that was starting in 2nd with a single disk.

I'm not saying there's no shock durning a drag race.. I'm saying the trans will live in 5th or 6th for a while with a crap load of power. It's been done.
 
I'd be interested in what you find, OP. I run a 5600 at around 450 hp. I tow really heavy when I do and would love to save a few RPM on the shifts. I'm hoping a new Hamilton cam soon will help, but at some point this tranny is going to need new synchros for 3rd. I've been double clutchin' it for almost three years now.

I think everyone realizes this big #600 POS will never shift like a race car......no news there...but if you find an improvement, be sure to post it up. :D
 
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Double clutching ain't bad. I'm used to it.

I have no need, but I'd think if you kept the cost down you'd sell a lot of em to guys like Jory.
 
WTF is that supposed to mean? :poke: :hehe::hehe:
Ummm.....

Uhhhh.....

Welllllllll....










More than stock work trucks. If you want to race a truck tranny isn't the ideal tool. If you want something fun to drive that will get you through pastures and tow HEAVY a manual tranny Cummins is a great option.
 
Got any de-icer?

LOL

JoryandTrenna.jpg
 
Are you talking about machining the dog rings to accept a large 4 lug type pattern like the things liberty does to older 4speeds or what?
 
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