The Ultimate NV5600 Users Thread

[blacksheepdiesel]

Ilian,

The question I would ask the Dodge mechanic is what proof does he have that the overfilling caused the failures? Blumenthal's in Oklahoma City is the only re-manufacturer of N5600 transmissions for Dodge. So when that mechanic you mentioned installs a Dodge reman NV5600 it comes from Blumenthal's who tell their customers to overfill the transmission. I'll bet the mechanic does not know that! No one has ever explained to me how overfilling the NV5600 can cause damage. Indeed, I even put 12 qts in as an experiment one time (which brings the level to the bottom of the rear seal) and what I discovered was that the oil will come out the rear seal as you go up hills until there is about 7 qts left.

As far as capacity with add on coolers I would recommend the 7 qts plus whatever amount the coolers add in capacity.

Godspeed,
Trent

 

[ILIANBG]

Hi Trent,
thanks for the information, it's good to know what the rebuilders recommend overfilling.
I will add some (more then 2qt then) to get it to 7qt capacity. I do not have coolers yet.
Do you personally use Amsoil? What do Blumenthal's recommend and is 7qt their advise?
Ilian

 

[blacksheepdiesel]

Ilian,

Blumenthal's uses Dodge fluid packaged as Blumenthal's brand and they do recommend overfilling but not sure exactly what they are telling folks currently. Standard Transmission and Gear in Ft Worth is saying 7 quarts.

Personally I have used the Blumenthal/Dodge oil and Royal Purple. For me the Royal Purple seems to make for easier shifts and is much less expensive. Once my 6 speed started shifting hard, grinding as it went into gear. It seemed the synchro's were clogged with something. Admittedly I was well past the 100,000 mile oil change point that works well for me personally. Swapped the Dodge oil out and put in Royal Purple and immediately had easier shifts with no grinding and within 10,000 miles (which is only a month for me) it was shifting as if it was brand new.

Godspeed,
Trent

 

[Grizzly]

Grizzly,



Great question. It can be safely said that the 5600 is safe for heavy mountain towing as long as you downshift on steep or long pulls to keep engine speed up. I believe this also keeps heat down in the transmission and reduces stress on components. The engine is stout in stock form and then adding power modifiers that add power low in the rpm band can give a false sense of security to the driver. While the engine might be able to pull the grade it may do so to the detriment of transmission components.



I have never heard of a 5600 or G56 housing break because of heavy mountain hauling. If someone has, please chime in here. Someone's bad experience can be wisdom for the rest of us.



Godspeed,

Trent

Thank you blacksheepdiesel for a great thread.



george

 

[Grizzly]

blacksheepdiesel, GTOWag posted this on an ongoing thread, "NV5600 lube update". What's your take on it, since I trust your opinion more.



george



"I recently had some work done on my NV5600 transmission, The gentleman that worked on the transmission told me and even had it printed on his invoice: “Use Valvoline 5w30 Fully Synthetic Motor Oil only! Do not use Lucas or any additive, Synchronizer damage will result. Install ground straps from transmission to frame and body”.



I have never heard of this before and wondered if anyone else has. I have read many TDR threads concerning what oils people are using, but have never seen this one mentioned. He claims he has thousands of NV5600's on the road and has had no problems. Valvoline is available almost anywhere auto parts are sold and is a lot cheaper than other options. Has anyone else used, or heard of this before??"

 

[RVTRKN]

RVTRKN: you are correct that you can't go wrong using OEM oil. You are also correct that it is very expensive compared to other oils. To say it is the only oil safe to use is not true and I say this from much experience. It seems the NV 5600 is a very finicky creature and some 5600's shift better with one brand of oil better than others. Every owner will have their own preference.



The most important thing concerning oil was stated by steved above that the correct specification of oil is used. Never gear oil! If you are going to have a shop change oil in the 5600 then take the oil to them that you want put in it and tell them how many quarts to put in.



Godspeed,

Trent

I'm just pointing out the fact that there are different opinions and oils used, and that they can vary on that point, but the only true choice you can't go wrong with is OEM. If you have good knowledge of what works and want to risk it, its your trany. I have researched other oils before, but that was for a specific gear oil, and found the same oil under a different name for half the price.

 

[steved]

Comment removed

 

[blacksheepdiesel]

RVTRKN,

Agreed.

Godspeed,
Trent

 

[blacksheepdiesel]

Grizzly,

From personal experience I have no reason to try engine oil to see if it might work. It may, or may not. I agree with steved, the most important aspect of NV5600 oil is meeting OEM specs and I doubt if engine oil does.

Grounding straps???? What the heck for??? Never heard of this.

Godspeed,
Trent

 

[NIsaacs]

Manual transmissions are not high tech components. They have been around for ever and while they are not created equal they are all very simular.



Dana/Spicer/Eaton transmissions have used 50w heavy duty engine oil for ever. In this age of synthetics they now recommend 50w synthetic engine oil as the #1 choice for all climates. #2 choice, depending on climate, is regular heavy duty engine oil in 30-40-50w. #3 choice is 75-90w.



Keep the oil full and keep it clean.



Nick

 

[macdaddy]

I believe some of the alloy's found in the 56 honey are lubricant specific. The OEM spec covers this... .



I really dont understand the need to venture away from the OEM oil?. Especially when you consider the small amount it uses and the required change intervals.



Mac

 

[steved]

Sorry, I won't post anymore...

 

[blacksheepdiesel]

The intention is to provide info, not argue about oils or who is the best rebuilder, etc.



Godspeed,

Trent

Just a reminder...



Godspeed,

Trent

 

[GCroyle]

Manual transmissions are not high tech components. They have been around for ever and while they are not created equal they are all very simular.



Dana/Spicer/Eaton transmissions have used 50w heavy duty engine oil for ever. In this age of synthetics they now recommend 50w synthetic engine oil as the #1 choice for all climates. #2 choice, depending on climate, is regular heavy duty engine oil in 30-40-50w. #3 choice is 75-90w.



Keep the oil full and keep it clean.



Nick

I think some of the engineers that design the modern pickup manual transmissions might take some offense in the not high tech statement. But I do not see any relevance to what Dana/Spicer/Eaton transmissions use compared to our NV5600. The D/S/E gearbox is completely different.



I have 99,000 miles on my NV5600 and I will not put any fluid in it that does not come from a MAJOR manufacturer and it must have the Chrysler spec reference on the container. And I change it regularly, it's my choice.



I have only seen the insides of one failed NV5600 and it was lack of oil failure. But if NVG specifies a spec for it, I'm sticking to that requirement.



I have owned 3 Chrysler vehicles with M/T's NV5600, NV4500 and my Daughter had a Neon each one took a specific fluid. Period.

 

[NIsaacs]

Thats cool, i do not mind in the least what you want to use in your transmissions, I have nothing against OEM specs.



The relevance is, manual transmissions are very simular in design. They all use a case, bearings, shafts and gears. You can totally disassemble two identical transmissions, mix all the pieces and parts in one big container and reassemble them using mixed pieces, (not high tech).



I don't see why the mystery shrouds the NV5600.



Nick

 

[GCroyle]

Does a transmission from a Class 8 highway truck have syncronized gears? If it does, are they using the same "friction surface" as our NV5600?



I don't have my magazines here at home to research they are all at work, I think Joe just did an article a while back on his rebuild, I bet he has some details in it, anybody have a copy handy?

 

[NIsaacs]

Using an Eaton 13 spd for example, the main gears do not use synchro's, however the high and low side shift does, as does the high and low splitter. The medium duty 5 and 6spd's do also. Most class 8 trucks use a clutch brake for assistance in stopping the rotating mass for initial gear choice rather then a synchro.



The NV5600 started life as a medium duty truck transmission, with the corresponding larger input shaft, (1 1/2-1 3/4) it was rated 650 lbs tq. When it was downsized for the pickup, they first used the 1 1/4 input shaft with some failures so it was upgraded to the 1 3/8 input. The input shaft size is key in any manual transmission because of the larger components that accompany the larger diameter.



The Clark transmission in my Ford is also a medium duty, however with my use of the standard 1 1/8 Chevy pickup sized input shaft, I derated it's capability to the point the Cummins overpowers it.



Knock on wood, I have yet to have a synchro failure in any of my trucks.



Nick

 

[GCroyle]

Nick,



Thanks for the info, I'm going to bow out on this one and let the guys with hands on knowledge rather than my bits and pieces comment further. I sure would like to see one of our syncros new vs. used.



Regards,



Gary

 

[NIsaacs]

Gary,



You are welcome, the info may or may not help you. One thing I do when stopped, like at a light, is stop the transmission rotation with 1st gear then slip it into 2nd and go. That helps with synchro wear by using a gear that gets very little use. I do this with gentle stick pressure and doubt that most times when I shift, the oil film ever gets forced out of the synchro as it matches up with it's other half. I have found synchros to be very durable, keeping in my mind, the leverage of the long shifter stick.



Nick

 

[Dieseldemon]

I have over 400000 miles on my Gv5600 and it has never been opened up I have been using OEM lube only and have never had a problem.