NV 5600 questions:

[Stab]

I've read the previous threads on the sixth gear noise on the NV5600's... ... I've got bad noise after ticking in sixth gear for several hundred miles. Is there any current info on the dealers taking care of this? (only 50k on this 04. 5) Do they replace the whole gear box or repair yours? Has anyone had the dealer replace the factory clutch with an aftermarket while the trans is out?? Fluid concerns; what's everyone using other than the factory fluid?



Thanks TDR!

 

[AlaskanCummins]

Hey,



I had sixth gear just go "boom" one day as I was passing someone. This was at about 50K miles on my 04. 5. Drove it home rest of the way (125 miles) as she ran fine in all other gears. Dealer rebuilt transmission, and I'm not sure what type of fluid they put in it.



I've got a South Bend ConOFE clutch that I put in way before this happened. I'm guessing it had to do with having my Banks Sixgun tuner on #6, or maybe just towing too many miles in 6th gear. They did tell me though that they rarely see any problems with our transmissions. Oh, and I was running Redline MTL fluid in it when she went out.



Since then, I've removed my Banks tuner and went with Smarty... ... Much gooder!!



Hope this helps!

 

[Stab]

How do you like the SB ConOFE?? Peddle pressure? My truck isn't used much, but when it is it's towed (or pulled) heavy! Thanks for reply.

 

[jelag]

We've had problems with a NV5600 in one of our trucks... . We've learned form NV that this transmission is not designed to run in 6th pulling a trailer... . we tow all the time... .

We are now taking the transmission out of our 04 for the second time for repair with close to 300K miles... . The last time it was out the vendor who did the work had real problems... . so we are at a loss who have do the work. .

 

[mberry]

Jim,

Didn't Blumenthal's buy all the NV manual trans stuff? I think I read where they bought all the NV4500 stuff but I'm not sure about the 5600. They could be a resource at the very least.

 

[AlaskanCummins]

Stab - I like the ConOFE much better than the ConFE. This is because the FE was way too grabby for me, as it has ferrus material on both sides of the disc. Having the OFE (organic one side/ferrus on the other) made the truck much easier on take off and trailer towing. I upgraded the hydraulics which wasn't necessary, as I don't have a dual disc setup. So, pedal pressure and actuation is about the same as stock.



I've heard elsewhere that towing in sixth is a no-no on these transmissions. Since I had my sixth gear replaced, I really haven't towed much; only a 2 place snowmachine trailer with a couple of sleds on it. What I don't like is the fact that if you do tow something in the 10K - 15K pound range and you're cruising on an interstate that's only got moderate hills, you'd be in 5th gear wanting to do at least 65mph and taching 2600 or so rpm. That'd suck on fuel mileage.



Why on earth would they build a transmission that couldn't stand the work load?

 

[DPKetchum]

You GOT to tow in 6th. No way around it. I've had horses and trailers delivered to me by hotshoters with 500,000 PLUS miles towing in 6th without a failure. That sounds like bull.

 

[MMeier]

Jim,



Didn't Blumenthal's buy all the NV manual trans stuff? I think I read where they bought all the NV4500 stuff but I'm not sure about the 5600. They could be a resource at the very least.

Blumenthals is the North American DC rebuild center for the 5600. They had several dozen on the shelves when I was back there a few months back dropping off my Getrag core from the 4500 conversion on my '93. Seeing as how the '03 is acting up real bad AGAIN... Have to shut truck off to get into reverse now when the trans is warmed up, and sometimes first... I'm tempted to try one of their 5600's... but damn, another $3700 for a trans R&R!!!:{:-{}:{ the 4500 shifts smooth as silk in thre '93, have about 3k miles on it since the conversion.

 

[Deleted member 995608]

The only time I get noise from (6) is when pulling a grade w/ 5er in-tow. Shift down and the noise goes away. No noise in (6) on the flats pulling.

 

[rbattelle]

We've had problems with a NV5600 in one of our trucks... . We've learned form NV that this transmission is not designed to run in 6th pulling a trailer... . we tow all the time... .

Jim, I believe that you've been told this, and I believe your experience. But my goodness, I find it hard to believe NV really never meant for this transmission to tow in overdrive.



Is there anyone left at NV (currently owned by Magna) who worked on the 5600?



Ryan

 

[jelag]

OK... . we've found 2 of our customers who rebuild this transmission so I have someone to go when we get around to it... .

But this time. . its the transfer case... . can you believe that after 300K miles the chain is so loose in the transfer case its slapping the case and the 2 gears that are the drive and driven gear are both bad... .

I've never had a transfer case fail in any of our other trucks. . The kit is on the way and with a complete set of bearings, seals, chain and 2 gears. . a little over $300. 00. .

We are chasing down the oil to change the oil in the transmissions and transfer cases on all our trucks before winter sets in...

rbattelle... I was talking to one of our customers who does these transmissions, and he's telling me that the NV5600 was not designed to tow anything over a light boat in 6th gear. . 4500-6500 lbs or so... . of course if you've seen some of my posts we often get this truck to tow a trailer that weights up to 20K lbs...

Had I known this before buying the trucks I would have ordered the 373 instead of the 410 rear ends... . we just can't get them fast enough in 5th gear with the 410...

The new 08 5500 I bought has the Aisan transmission and that truck runs very smooth at 75 mph and has over 38K miles... .

Thanks for the info. guys... .

 

[RBridenbaugh]

Jim --



Just curious. Had you been over filling the NV5600 that you use for towing that you are having trouble? If so by how much?



If not, are you planning to overfill when you change out your fluids for the coming winter?

 

[jelag]

In the past we've installed the correct oil (mopar) and have only filled it to the service plug... .

We know we overwork the transmission... we often tow a 22K lb trailer around the pacific northwest... . so we understand that we abuse it... .

The fact of the matter, if you look at the gears in the transmission, they just look under designed and we seem to loose bearings as well as the gears...

A good friend of mine has been in the transmission business in Indiana for all of his life... he's got the same feeling, that this transmission is not designed to tow heavy loads in OD... . And it comes to mind we've read something from Chrysler on this as well...

I just don't know where I've read this... . owners manual, or service manual... Had I fully understood this before I bought the 3 current trucks, 04, 04. 5 and 05 all with the six speed and 4. 10 axle we've have bought the other axle and driven them when loaded in 5th... .

My last comment goes back to transmission classes from school... that the straight through design of high gear, locking the input shaft to the output shaft would take all the side pressure off the counter shaft and other gears... as well as locking the input and output shaft bearings... thus the needle bearings that connect the 2 shafts together are not turning and have no side load.....

It only makes sense that the high gear is the gear of choice for most travel with the least wear on the transmission... .

It would seem prudent for the manufactures to build high gear as a straight through gear, and all the other gears to be of lower range... its only with the push for higher mpg that we've seen a big change in this technology... .

My last comment has to do with a lab test we ran in college using the lubrication properties of oil, ATF, gear oil etc... we found through our controlled study that STP and ATF mixed did the best job in preventing bearing failure... and I've often wondered if STP, Power Punch, or Lucas mixed with the special gear oil in this transmission would add to the film strength of the lubricant and extend life... .

OK I'm done... thanks for listening...

 

[DPKetchum]

Don't know about STP but the LUCAS had some bad reviews on Bob Is The Oil Guy forums.

 

[Stab]

Update:

Sixth gear teeth ground off (several) "typical gear failure", bearings and intermediate shaft replaced. All started with a ticking in sixth gear. Finally fully failed with a full load on trailer in sixth gear. Just got real noisy. Shifted to fifth and noise was gone. Drove to Dodge Town (Rapid City, SD) in fifth gear (150 mi) for service.



Kudos to Dodge Town! VERY VERY good service! Excellent Diesel techs!

Highly recommend them for service. $100 deductable and good to go!



We have had three trucks at this dealer and are happy with all!