From what I've read and know, the DMF in the G56 is sorry. Will a SBC DD will take care of this problem? B/c i want a newer truck but i'm scared I won't like the G56. I drove one in a 6.7. It felt weird to me. I think i need to go find another G56 in a 5.9 and see what I think. Either way I'm pretty sure I want an 05. I just don't know whether I want the NV5600 or the G56. That intercooler really doesn't bother me as it's a 1,200 dollar fix anyway. I'm not a big fan of the NV selective shifting but, I do love the pattern and I'm willing to deal with it if the G just isn't as good all around. I've read and read on this for hours. The answer's i'm looking for will have to come from someone who has OWNED both trannies in similar trucks. What are the ups and downs of the G56 when compared to the NV. I know the NV is harder to shift. But is it actually stronger? I know the G56 is a better shifter and has shorter 6th gear ratio's but, is it as weak as some people say? Help me here guys... I know "Pourin Diesel" said he has a list of reason's why the NV is better but he never elaborated on it.

Thanks, Bill

 

bump. Looking for some opinions.

 

I believe the G56 is a very good tranny, just saddled with a weak clutch setup. But the SBC DD fixes that issue or convert it over to a single disk setup.
I like the NV due to the .73 OD vs. the .79 for the G56. The issue now is the NV is out of production and parts are harder to come by. So treat it nicely and add an extra quart so the upper bearings get plenty of lubrication.

MikeyB

 

Since you have the NV in your 03, remember you're comparing a G56 to a broken in NV. Why do you want an 05? Because it's the last year of the NV? Is it because it's the last year of the 7/70?

I thought I read 6th gear is higher in later G56 equipt trucks, like the 06 + 07's. A G56 in an 05 must rev pretty high @ highway speeds.

 

I like my nv5600, more I'm used to it. I'd rather have the cast-iron case. With a little extra $$$, you can't go wrong on either, but the G56 will need a hydraulic upgrade sooner than a nv5600 if you start modding.

 

Well, that's what I'm saying. Do the majority of the people who switched trannies with the trucks like it, Or just accept it? If I get told that I should stay with the NV5600 then I'm going with an 05. B/c it's the last year of the NV. And like the looks of it. But, If I get told to go with a G, then I'd rather go 07 for the lower gearing and pray that TST makes a PMCR that will work on that year model.

 

I wondered what the G56 was going to be like when I bought it almost a year ago, so far it has been flawless, shifts beautifully the ratios are great for towing but empty could use a little longer legs out on the highway.

I have not heard of common G56 failures so far and there are a lot of them out there.

I wouldn't be affraid of it, if you go with the NV you are buying into an obsolete, "Albatrauss"

 

Now that was the answer I was looking for. Keep that kind of stuff coming.

 

Thanks, duely noted point as well. So, an early G56 would need a Gear Vendors for me huh. I've got 4 years in the army left and I never pull. When I get out I'll be pulling all the time for the family business.

See I'm going to Iraq again in a year. And I'm stuck between bombing the 03 or buying the "perfect" new to me truck.

 

I cant comment on the nv tranny, but I do have the G56 and I like it. It shifts pretty smooth and the ratios are good. The OD ratio is a little low, I run about 2400 rpm @ 75 mph. It could be a little higher for running empty, but it's just right for pulling a load. I've been looking into an OD box so I can have the best of both worlds.

The G56 truck that you drove probably felt weird to you because it wasnt broken in yet. Mine has about 50k on it and is pretty smooth, but my dad's new truck is still stiff and feels a lot different.

 

What gears do you have Zach?

 

I have had both transmissions with 3.73 gears both on 1 ton DRW trucks. I had a lot of trouble with the stock clutch on the 04. It would just slip on a hill with a good load. But a aftermarket clutch fixed that problum. And around the 25-30000 mile range the mighty cast Iron case cracked and spun a bearing.
On the 06 I replaced the clutch around 30,000 miles for a DD how it made it that long I will never know
I have had 0 problums with the G56 with most of my miles towing. My only complaint was the gearing 6th gear and 80 mph and the truck would scream which is why I went with bigger tires now its geared perfect.
Nothing wrong with the NV, I just don't think it is better then the G56.

 

Thanks, that's the comparison I'm looking for. Funny the 3.73's still don't put it in the right rpm range in 6th. But, from what I've read if you're going to replace the clutch anyhow, I should just get a G56 truck. Like an 07 and just forget about a TST.

 

I believe it has 3.73s based on the rpms. I havent looked for any tags on the diffs or anything else to confirm.

 

Well on stock tires and 4:10's @ 75mph i'm only at 2200rpm with my NV. But I read the 07's with the G have a little better 6th gear ratio than the 05's and 06's. Can't remember the specifics though. I'm leaning towards the G more and more. But in an 07 instead of an 05.