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Tranny no mo...G56 time?

2K views 12 replies 6 participants last post by  5.9 lover 
#1 ·
Well I blew my tranny the other day. Pulling my fiver with my family and the dogs. Luckily only 70 mi. From home. So my father in law could save us and come pick up my wife, kid and dogs.
So about 8k to build a bullet proof auto. Maybe I should switch to a manual.? I know I could do that for cheaper. The question is. 5spd. Or 6? How good is the G56? Is it worth the effort? It sure sounds sexy.
 
#2 ·
I see no reason to spend $8k on a transmission unless you have at least twin turbos. Until you get past 1,500 foot pounds of torque a m3ga converter and bigger input shaft (included) should not be necessary. Most triple billet tc are rated at 1,500 foot pounds of torque.

I would think that spending $4,000 would be tops for a rebuild with performance parts. You do not need the intermediate or output shaft unless you would seriously beat on your truck.

As far as a NV4500 goes it is not a strong transmission when subjected to extra hp or when it tows heavy. GAmes has replaced several 5 speeds before he upgraded to a 6 speed. The NV4500 has a weak 3rd gear. Beat on that gear and you will replace it given some time.

Look at this.
http://www.cumminsforum.com/forum/9...uto-tranny-upgrades-increased-hp-engines.html
 
#3 ·
After rereading all of the posts about the G56, I think Im going for it! I have allways hated the auto. Never shifts when I want it to. So what upgrades are there for the G56? I know I want a late year g56r. A South Bend Clutch and Flywheel. Maybe the torque shield? What does Lasersmith do to his tranny's?
 
#4 ·
There ane no upgrades for a G56, unless you think your engine produces enough power to warrant a girdle. All parts are only available though Dodge, so if something breaks, forget any aftermarket parts. My conversion from a NV4500 was in the $3000 range, after I sold the serviceable NV4500 and associatd parts. With all that said, I have put about 300k miles on mine without a hickup, three times the service of the average NV4500, and it is still quiet as can be. One of my recent trailers was 16,200 pounds that was towed through the Siskiyous of southern OR/northern CA.

There are several posts about the conversion here and in the turbo diesel register (TDR) website. The newer version has a higher O/D ratio, but to tell you the truth, my '06 trans is giving me better mileage than the NV4500 did.
 
#5 ·
I hated my auto before I built it. Now it is built and has a lockup switch and I don't mind it at all. If I need a specific gear, I can easily manipulate the trans to be in the gear i want by turning off o/d or selecting a gear on the shifter. It's nice to just push the go pedal and move instead of going through 5 gears just to get up to speed. But I do love my 5 speed sometimes. I have always wanted to try out a G56 too. I guess it depends on who drives it the most and what for. I will never hand over my 5 speed to my wife or any other newbie, but the auto I would let anyone drive.
 
#6 ·
Well after further reading. I'm going with an nv5600 instead of a g56. A lot tougher. Easier to fit too. I found a pedal assembly. And a cross member off an '01 truck that had a six speed. Now I just need to go get me a nv5600....
Does anyone know where I can find a floor console from a manual '01 truck?
 
#12 ·
Well after further reading. I'm going with an nv5600 instead of a g56. A lot tougher.
A lot tougher is debatable. G56s are bolted to engines with 350hp/610tq, while the NV5600 was bolted to a 325/600 engine. What isn't debatable is the shortage of NV5600 parts. In addition, Standard Transmission in Ft. Worth, one of the largest and best known rebuild company in the country, will not sell a rebuild without a rebuildable core for exchange.
 
#8 · (Edited)
Agreed.

After rereading all of the posts about the G56, I think Im going for it! I have allways hated the auto. Never shifts when I want it to. So what upgrades are there for the G56? I know I want a late year g56r. A South Bend Clutch and Flywheel. Maybe the torque shield? What does Lasersmith do to his tranny's?


A well built auto will hold more power than a manual anyway. A good VB can shift quite nicely. A full manual VB will shift exactly when you want to, and only then
 
#9 ·
A well built auto still won't shift when I want. Can't downshift as much, exsaust brake sucks with it...and is still controlled by a computer. Pretty sure I fried my TC with my exsaust brake. If I blow the nv5600, I'm putting in an Eaton.
 
#11 ·
That would be the point my friend. Driving my other truck with a five speed, I hardly use my brakes. To each his own. That's why they make both.
 
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