G56 Failure
09-17-2006 | 08:37 PM
#212
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From: Texas
I have an 05 with the nv5600 and 2 of my friends have 06's with the g56 we decided to race stock for stock and it seems in about 5th gear I pull away on them pretty good I don't know the difference in the gearing between the 2 but it feels like the nv is certainly the better tranny for the cummins. Also in a sled pull this year I have the the edge juice on my truck and my other friend with the 06 has the crazy larry. we pulled back to back both using 3rd low on stock clutchs I used the 100 horse setting on the edge he used crazzy larry and I pulled over 13 feet farther then him and I mean our trucks are identical same toolbox same tires everything except for the tranny. Not saying the g56 are junk I just personally think a cast iron case is better than an aluminum one. By buddy also says when the clutch gets hot it is very hard to shift his truck I don't know if anybody else has had this problem or not.
09-17-2006 | 08:49 PM
#213
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From: Dakotas
I have pulled the last three weekends and havent broke anything I couldnt do that with the g unit and about the nv5600s breaking yeah im sure there are some but they have been out since 01 so there are a lot more of them out there the gunit is a year and a half out. I thought the gs were the best too till i broke two of them and they probably still are I just had a streak of bad luck.
09-17-2006 | 09:44 PM
#215
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From: St. Charles missouri
Well whatever but our trucks are dead even till 5th and 6th gears. the I start pulling away very slowly. I just don't see how anybody would think and aluminum tranny is better than a cast iron? The only thing aluminum has going for it is it takes away heat better I really can't see it beeing any better expecially if you are going to be pulling anything real heavy with it. All my buddies that have the g56 that have drove my truck say that they wish they had my teansmission instead of the g.
09-17-2006 | 10:18 PM
#216
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From: Pattonville, Texas
Aluminum has a number of advantages over cast iron or steel in automotive applications. OEM and aftermarket aluminum cylinder heads, engine blocks, intake manifolds, pistons, connecting rods, manual transmissions, bellhousings, center-sections, blah blah blah.
Aluminum is usually spec'd because of it's performance advantages, certainly not because it's a cheaper alternative to ferrous metals!
Aluminum is usually spec'd because of it's performance advantages, certainly not because it's a cheaper alternative to ferrous metals!
09-17-2006 | 10:42 PM
#217
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From: Olive Branch MS
Amen to that, Lord knows aluminum is not cheeper than steel. With aluminum, they design structural integrity into the component and make it as strong as the steel alternative. With steel, the just add more meat to it to make it stronger. I think both cases are equally as strong. Its whats inside that counts to.
09-17-2006 | 10:49 PM
#218
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From: Pattonville, Texas
OEMs tend to use aluminum because they can get the same strength as iron with less weight and more dampening of vibration/harmonics.
The aftermarket pieces usually are both stronger, lighter and longer-lasting than their steel counterparts.
Since the G56s are (supposedly) a couple of hundred pounds lighter than the NV5600, the effective payload of the newer Rams is that much greater...
The aftermarket pieces usually are both stronger, lighter and longer-lasting than their steel counterparts.
Since the G56s are (supposedly) a couple of hundred pounds lighter than the NV5600, the effective payload of the newer Rams is that much greater...
09-18-2006 | 09:08 AM
#219
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From: Kentucky
Guys trust me i will get the camera out and show you what broke this last time it is the worst design i have ever seen and i sled pull in second hi not sixth low I was talking about towing with the new tranny. Breaking in the tranny had nothing to do with the piece that holds the bearing breaking off and letting the countershaft fall out and lay in the bottom of the tranny but i sled pull and it should have broke.
09-18-2006 | 09:10 AM
#220
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From: Kentucky
Amen to that, Lord knows aluminum is not cheeper than steel. With aluminum, they design structural integrity into the component and make it as strong as the steel alternative. With steel, the just add more meat to it to make it stronger. I think both cases are equally as strong. Its whats inside that counts to.
Who has broke a nv5600 case I know of one broken g case?
09-18-2006 | 11:26 AM
#221
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From: Olive Branch MS
My grandfather
Sounds like he had a similar failure to your G only in a 98 with the NV. A shaft support broke and let it drop down and in turn ruined the complete assembly. He was pulling up out of a field with a load of cows and it just let go. I figure it was a casting error.
Check out a MACK transmission sometimes. Thats what they are known for. Building the strongest rears and trannys. Tell me what you see??? I can get some pics if you need them. They have been building them that way for many many years. You can make Aluminum hold up better with some design to it.
Sounds like he had a similar failure to your G only in a 98 with the NV. A shaft support broke and let it drop down and in turn ruined the complete assembly. He was pulling up out of a field with a load of cows and it just let go. I figure it was a casting error.
Check out a MACK transmission sometimes. Thats what they are known for. Building the strongest rears and trannys. Tell me what you see??? I can get some pics if you need them. They have been building them that way for many many years. You can make Aluminum hold up better with some design to it.
09-18-2006 | 01:46 PM
#224
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From: Dakotas
on my NV5600 the case was shot. I never looked at it first hand The mechanic said the bearing spun in the case and where the bearing is held it was cracked. I was just happy they were getting me a new transmission and not fixing the old one. Wish I would have looked at it first hand 
I expect my G56 to hold up to sled pulling and all the other loads I give it. Any one ever kill a transfer case I blew one of them in my 04 too.
I expect my G56 to hold up to sled pulling and all the other loads I give it. Any one ever kill a transfer case I blew one of them in my 04 too.