NV5600 Rebuild. Any Lessons Learned?

4x4dually

4x4dually

Moderator
Staff member
Joined
Jan 22, 2007
Messages
32,083
I have been fighting synchronizers in 3rd gear for over a year by double clutchin' and RPM matching. Now, if I stop at a light and go to neutral, I'll be danged if I can't hardly get it into 1st, 2nd, 3rd grinds, or any other gear. Reverse is a biatch too. I'm wondering if the pilot bearing isn't draggin' or the factory hydraulics aren't going out and the clutch isn't fully disengaging.

Anyways, suggestions on the problem are welcome, but if you were to open up a NV5600, what would be worth replacing since it is open? Also, if anyone has any literature showing the rebuild process that would show steps and what tools are needed, I'd greatly appreciate a copy. I'll try it unless I need some 100ton press or something crazy.

Quote from the shop in OKC is parts (synchronizers) $375, bench charge $450, remove and install tranny in truck $150. I think the $150 is the best deal! I REALLy don't want to drop a grand on this sucka, but I might have to.

Thanks.
 
Well talkin to other diesel shops aroud here I have asked as well and they have told me that 24v 6speeds had bastard parts in it and hard to find and the ones in cr are everywhere just some advice not sure how true though I have look though the factory tech mannual shows it don't look bad though to eliminate ur clutch get in gear and clutch it and rev it and see if it moves
 
Dude....punctuation is your friend. :hehe: Thanks. I'm wondering if the 3rd gear synch's didn't destruct and the material from them is ruining the others. I guess a fluid drain would tell me how much crap is in them.
 
I have heard that you need some crazy presses to fully disassemble one. i havent done it myself, the tranny guy i found hooked me up. he replaced the 6thgear set, and the reverse synchros for $850, then when I had a bearing noise, he tore down, inspected and put the whole thing back together for $120, said the bearings were all good upon inspection but the noise went away after I put it back together.
 
I dont think its your hydralics, when mine failed it the clutch pedal would be to the floor and the clutch would slowly engage. Made for alot of planned shifts.
 
Do you have an aftermarket clutch? If you do and you don't have the upgraded hydraulics, then I would just about gaurantee that its your hydraulics. All of my buddies trucks that have had these clutchs had the same symptoms you are having until they put the better hydraulics in. Just my experience with them.
 
I have a South Bend Con OFE which feels decently heavy at long lights. That's why I go to neutral most of the time. The clutch does not try to creep with the pedal to the floor but I was wondering if that still wasn't the problem. I'd sure like to put the two-three-four hundred dollar upgrade (what ever it is now) on instead of pulling that heavy SOB out again. On the flip side, I'd hate to drop that $$$ and find out it still shifts like a step-child and then drop another grand. Stock sync on Rev shelled at 34K miles. And I mean shelled, completely trashed. Those are easy(ier), they are on the tail shaft. But, I really don't think I want to tear into the rest of it.

I'd sure love to drive it to a "competitive" tranny shop that will un-doubtedly do it right and check everything, but doubt I can afford that. The place in OKC is Bluementhal's (sp?). They did my neighbors '01 and he had to take it back so I'm worried.
 
The Hydralic upgrade is in the low $200 range from SBC or a vendor. I like mine on my stock clutch.
 
I know, but who else do you take it to around here Nick? Is not like we have anything "performance" or "track proven" folks around here that can build anything to my knowledge. I don't want to flip the coin in the yellow pages. :D Ideas?
 
Talked to Peter at South Bend. He recommends Bluementhals. :( :D ?????
 
I've been going over this in my head for a while. I'm gonna have to redo mine sometime. I think I've found someone I'd trust with it.

I'd PM Aaron about it. I know he knows someone that should be able to do it. See above:D
 
I think first I'll drain fluid and try to flush (flush with what? Diesel?). Let it settle in a clear container and see just how much schrapnel is in it. Maybe all the other syncs are just full of crap from the detonating 3rd? Funny thing, once Attitude reads 150F+ on tranny fluid temp, it shifts fine. Whiskey Tango Foxtrot?
 
Mine was pretty notchy for a while, I did drain and fill, now the only issue is a blown third gear synchro. And I don't mind double clutching.

I didn't actually flush it. Old fluid was nasty, new stuff was pretty much clear.
 
I think our trucks must have slept together in college, Nick. :hehe:
 
I am glad someone else has these same problems. Mine never goes into reverse, if I put it in neutral have to hunt a gear it will fall in and then roll it up and put it in first or second. Nothing really fun, guess mine is due for something new under it. and it did it with the stock clutch, i just don't want to dump the money on it yet. Mine shifts better if I drive it like I stole it!!
 
My other truck got stubborn when goin into gear also, but once you were movin it was better! I would look at the throw out bearing and clutch disc first! I was pretty hard on my FE and the disc had gotten very hot and wasnt true anymore, which caused hard engagement! just a thought
 
You must log in or register to reply here.
Back
Top