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To all you nv 5600 guys...

3380 Views 32 Replies 12 Participants Last post by  B52doc
Did a tranny swap into a 2012 6.7 auto. Swapped in a 5600 and it's hard to get into gear when stopped. I used an adapter plate off of a 03-07 common rail so everything is the same. Ran it for around 8000 miles and pulled the tranny out to be rebuilt at blumenthals. Got the tranny back in last night and sure enough it's still just as hard to get into gear when stopped. Feels like clutch isn't disengaging or something. I am running a South Bend 3250 for a 2004 nv5600. I purchased the clutch brand new 8000 miles ago. When I put the tranny in last night I put in new pilot and throw out bearing also.

I called Peter at south bend and he had me test the hydros with a steering wheel puller and they tested out good. Any ideas on what it could be?

I was leaning towards bad pressure plate but I'm no expert. Peter said tear in apart and send him pictures of everything. South Bends customer service is top notch by the way. Just looking for some opinions/ideas.
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How hard is it? The 5600's are all pretty much a pita to get into 1st & R with a dual disk…..Alot of the times it's easier to go into 2nd & then straight to first, instead of trying to get it in first to begin with
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How hard is it? The 5600's are all pretty much a pita to get into 1st & R with a dual disk…..Alot of the times it's easier to go into 2nd & then straight to first, instead of trying to get it in first to begin with
Well here is alittle more...went to work today and was planning on dropping tranny tonight, fire up truck after work and to my surprise it glides into gear no problem, shifts awesome on my ride home. I leave ten minutes later and it won't go into gear again, I'm talking any gear. I think maybe my discs need re-hubbed. They had some burrs on it from stabbing the tranny multiple times. Could that be a possibility?

Also might replace pressure plate just to be safe.
Mine is a royal pain, generally have to jiggle it to get it into gear, I think I usually drop it into 1st then 2nd to take off. Other times it's butter smooth, but mostly it's a pain.
My nv5600 was a pain also 1st was always hard second not as bad and had to put into 5th before reverse was possible. This was all the same before and after the southbend clutch/hydros. And 6 fresh quarts of amsoil. Other than tricky shifting it was one stout gear box in my opinion for a light duty truck.
Shifting better and better, seems that it had to wear in the new input shaft.
Do you use powdered graphite on the input shaft
Do you use powdered graphite on the input shaft
No I did not. I didn't know if the input required some type of lube or not. Shifting problem is back so I believe the disc/discs aren't sliding on the input as they should. Do you guys recommend getting two new clutch discs or would I be able to get a file and clean up the disc hubs and input?
I would try the file it down method as you will be making the hubs slightly bigger and the shaft slightly smaller so it should slide easier. I imavine when the sliding disc hubs are made they are all with one or two thousandths of each other so nrw discs will give you the same trouble.
Well I pulled the tranny out tonight and I can't see anything obvious that shows why it isn't shifting right. I took the clutch discs and slide them on the input shaft and they slide with ease. This leads me back to the pressure plate. I got a bunch of pictures to send to south bend tomorrow so we will see what they say.
Keep us posted on what happens.
Keep us posted on what happens.
Will definitely do that. I'm to the point of wanting to sell this rig. Anyone want a 2012 that doesn't shift right haha?
Sent pictures of clutch to Peter at South Bend. He couldn't really see anything that stands out in the pictures but he is sending me a brand new clutch to see if that solves it. I can't say enough about Peter at South Bend, not because he is sending me a new clutch but because this guy is dedicated to keep his customers happy and goes above and beyond. So if the clutch don't fix the problem the tranny is going back to Blumenthals to be checked out again. If that don't fix it I have no idea where to go from there.
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My 5600 shifted just like you are describing, to the point that I hated to drive it. Switched to amsoil 10w30 oil (overfilled by 1 quart to improve rear bearing lubrication) and a tube of limited slip differential fluid. It took about 500 miles for it to start improving, but the truck shifts like a dream now. No issues what-so-ever.
The oiling passages on the NV's can use improvement. I had a nicely built one in my truck until the input shaft went whacky from the T/O arm jumping off the pivot ball. It shifted very smooth. The standard reman unit shifts like crap in comparison.

Also, multi disc clutches are a bear in general. Even when operating smoothly there are 4 or 6 friction surfaces that are gliding over the floater plates, flywheel or pressure plate. This creates unavoidable drag that makes shifting challenging. On the current trans I cannot ever access 1st at a standstill. I need to have a bit of roll to get in to first. Reverse is a supreme slut always but I can also always get in without trying another gear.

Honestly, the G56 is a much more reliable shifter but it isn't strong enough...
After only 50 miles of driving there was already brass in the new tranny fluid...we just put a 3250 in my buddy's 01 nv5600 with almost 200000 miles and his shifts a heck of alot better than mine.
Wow that sucks. I'd be irate with the trans shop. Unfortunately I've been in a similar boat.

Just FYI, I've experienced many incompetent trans shops for these trucks in my area. Only good one I've been recommended to is Standard Gear in Dallas or Fort Worth? TX. These transmissions are in a weird size range right between passenger car and industrial trucks. Your average trans shop doesn't have the experience, knowledge or tools to work with these things successfully.
Wow that sucks. I'd be irate with the trans shop. Unfortunately I've been in a similar boat.

Just FYI, I've experienced many incompetent trans shops for these trucks in my area. Only good one I've been recommended to is Standard Gear in Dallas or Fort Worth? TX. These transmissions are in a weird size range right between passenger car and industrial trucks. Your average trans shop doesn't have the experience, knowledge or tools to work with these things successfully.
Well I sent it to Blumenthals in Oaklahoma...I was recommended to them by a bunch of people. They are real good to deal with and said will go through tranny again if this clutch dont fix it.
I've found it's a lot easier to get into gear when stopped by double clutching it. The shift pattern is a little ragged though - kind of difficult to find the right gears - but that's maybe because I just got it. Is there a short throw kit for it?
My NV is pretty much what you described. Shifts great (once its warmed up) but if I stop at a light it can be a pain to get into 1st or 2nd. Shifting between all gears can be notchy at times due to the short shifter kit. Overfilling did help a lot.

Giving it a little throttle or shifting into 3rd first generally does the trick. I think it's just the nature of the beast.

Maybe it needs to be broken in a bit?
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