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Broke my NV5600 today

3K views 8 replies 5 participants last post by  Massuh_Nate 
#1 ·
Well it finally happened. I wasn’t sure it ever would but here we are.

Cruising to work this morning about 8 minutes (6 miles) into my commute I reached the highway. As I was merging on I rolled into the throttle about 45% in 6th gear and not 1.5 seconds later I heard a crunch and the trans let go. Pulled over to the side and cut the truck off and tried to see what the shifter would do. Won’t go into 3rd or 6th and the shifter almost gets stuck in 3rd. Yikes.


I started the truck back up and verified that 2nd, 4th, 5th and reverse were working. Trans is making a pretty bad sound but I figure it can’t get a whole lot worse so I limped it back home in 5th. Drove completely normal despite the transmissions cries of pain.

I got ahold of a couple of rebuilders and basically until they see what’s wrong I don’t know what it’ll cost to fix it. I’ve decided I’m going to remove it and disassemble it myself. I was going to take it out anyways and it’s not too terribly hard just to get into the case and take a look so that’s where I’m going to start. Curious to see what’s cooked


If you guys have any ideas about what broke let me know, I’ll update this thread with the carnage.
 
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#2 ·
Cheapest I found without a core deposit. I don't have the link its on my work pc. I though though about just going with a g56 transmission since their parts are easier to find compared to the 5600 but there is a lot more work with the croossmember, driveshafter,a nd possible change in 4x4 splines to mate to the g56
 
#7 ·
Ive seen the videos on Bruce Wilson's channel with that superstick nv5600 and man, that thing is a bad unit. Id spring for that if It were me. He shifts that trans like a damn corvette.
 
#9 ·
Well I got the transmission rebuilt and back in the truck, it drives great!

Upon tear down I found both 6th gears completely stripped of all of their teeth but that was the only damage. Everything else was in fantastic condition, I was surprised.

The rebuild wasn’t bad at all, I used a 20 ton harbor freight press and it had no issues pressing the big gears off of the countershaft. New synchros and bearings throughout, new input shaft, and a new 6th gear pair that I had cryo treated. Excited to have my truck back. All in cost to do this myself was about $1200. Hardest part was setting the gearsets back into the transmission while lining up all of the shift forks and getting them to slide into their holes.
 
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