supr

The Penzoil Syncromesh also meets the spec for the NV5600, as per the mnual. I think most people have liked it. These trannies seem to have persoalities(like their drivers) and seem not to behave the same with the same fliud. Some people will like Penzoil, for example. some will hate it.
Same for all of them. At least get one that meets the Chrysler spec.

Clunk

I drained mine with the bottom PTO cover bolt then refilled through the top PTO cover bolt with Amsoil 5W-30 Synthetic Synchromesh Transmission Fluid last year and I'm well pleased and satisfied with the better shifting.

SIXSLUG

Some new info on the NV5600 after I had to have mine replaced! My trans guy is pretty well known for being an excellent mechanic and he let me in on a few points of interest re: the NV5600.

1. There is a modified case with an opening at the rear right lower corner that allows fluid to the rear gear. This occured around late 2000, this allows fluid to the back so these trans won't really benefit from an extra qt. Unfortunately you'd have to pull the transfer case to find out. If you don't know the extra qt can't hurt. Rebuilds have 2 or 3 1/2" holes drilled in this location if the rebuild shop is a competent one.

2. The wrong fluid is what kills the backing plates (synchro's) in these trans. It doesn't take a whole lot of driving to accomplish this. My new trans will run the Texaco/Chrysler fluid until the warranty is up, when I'll switch to the Amsoil version or the Redline. I haven't investigated enough yet to make a decision. The wrong fluid is usually put in at the local Quickie lube, the tech sees a big cast iron case and just assumes gear oil is the required lube.

3. Towing by the front end can mess up the backing plates in a hurry if the trans is in neutral and the driveline is in place. When towing these rigs, make sure the wrecker drops the drivelina at the rear end and straps the driveshaft up. I got a $45 bill for this and consider it very cheap for the headaches it could cause down the road if it reduces the useful life of my trans.

4. You own a truck that was made primarily for pulling a lot of weight. The more I have in mine the easier it shifts and the smoother everything is. A trailer increases this feeling even more. The trans is not meant for racing or flying thru the gears, it's big, heavy and almost bulletproof but needs a moment to line everything up before smoothly slipping into the next gear. When going from a stop or forward gear into reverse push toward the 'R' and count one, two, three and it should slip right in. Forcing it just causes stress on the internals.

5. My truck was purchased used w/53K miles on it and my past experiences w/ 1 tons and larger trucks made me notice the trans shifted kind of hard and toothy but from what I've read on here I assumed that was pretty normal...wrong! My new trans shifts very smoothly and I was very surprised the first time I drove it that I had been driving it the past 2 years with damaged internals.

By the way, My old trans was pretty much destroyed during disassembly, some of the components were so tight that a lot of heat and a huge press were needed to get it apart effectively rendering the main shaft useless. I was amazed at the size of the mainshaft in this trans and my trans guy said that I couldn't possibly break it but the wrong fluid is like cancer to these trannys. Good luck with yours!

Kurt

supr

Good Post!

I thought there were no more NV5600 to be had. Was yours rebuilt?
Also, your truck being 2001.5, I guess the holes were in your tranny for proper lubrication?
What did it cost?
What did they recommend for a chnage interval?
Finally, it appears running an extra quart in later models may be a waste of time?

SIXSLUG

According to my trans shop he wasn't aware of any availibility/supply problems with the 5600. Mine is a rebuilt unit and the old one was sent in as a core. It was billed at $2850 for the trans, $775 for the SB clutch and hydraulic system, labor was around $1000 and fluids were about $100. It arrived the next day after it was ordered.

My truck did have the lower lube hole, the cast in place one is a square oval about an 1" across. The rebuilds from earlier will have a couple holes drilled in the same place, about 1/2" or so. My rebuild had the later casting so it was essentially the same as my original.

He rec'd a change interval of 40K miles for my driving style, 25-30 for heavy pulling frequency.

Because of my warranty we are running the Texaco stock lube for a year and will replace with Redline or Amsoil after it expires. He said the extra qt doesn't hurt your trans, just your wallet. He doesn't feel its needed on the later 5600's with the passage.

Kurt

Clunk

Thanks for the info, that's a very good post.

Thundercraft

Excellent post SixSlug..... one of the best on any topic that I have read.

SIXSLUG

Thanks, I'm just trying to help out where I can! I spent some time asking around about my trans guy and got a lot of good responses about him. He's very knowledgable has a meticulously maintained shop and excellent communication skills. Plus I went over the truck the day I got it back and everything is tight and where it belongs, no loose ends.

Kurt

jefe4x4

This is a very cool thread. I wondered when to change the trans oil since the manual didn't even suggest an oil change before 100K mi. How could that be?
I'll be getting 5 qts. of Redline MTL for that 360 lb. beast.
All good suggestions.
regards, as always, jefe

jefe4x4

I changed the NV-5600 trans oil today. I pulled the PTO cover off, let it drain, then drove the truck onto some stands on one side only. Drained some more. I cleaned up the cover with a air rotor wire wheel, put a bead of "Right Stuff" sealant on and reassembled the cover. As far as the 17mm female hex nut, I put (3) 17mm nuts tight on an 8.8 bolt and used it as a tool with a ratchet. Opened easily. Nobody in town had any clue as to where to get a 17mm hex. I used Red Line MTL 70/80 as per your instructions. It was $9.99 @ Qt. at the auto parts store. Dodge wanted over $20 a Qt. for their corp. stuff. It is the same lube as used in the NV-4500.
With the truck tipped up high on one side, I was able to get 5 quarts into the case. It was kind of dribbling out on the last few oz., but got it done.
At 112K miles, the old oil was surprisingly clear. I must be a wimp it was so clean. It did have a myriad of tiny brass 'flakes' in it.
On test driving, I could detect a small increase in ease of shifting and downshifting. Not much.
Thanks again for all your ideas.
regards, as always, jefe

Clunk

Re-read the thread jefe!!!
The NV-5600 takes a 5W-30 syncronous transmission fluid, not gear lube...drain your trans and save it in a jug, maybe someone with another type trans can use it.
Make sure you put the correct fluid in your 6 speed.

jefe4x4

Clunk,
Uh... Red Line MTL is 5w-30 (and 10w-30) full synthetic transmission fluid. The 70/80 is the trans version of 5w-30/10w30 motor synthetic.
Anyone else think I've made a mistake?
regards, as always, jefe

brianpgriset

I've ran MTL in my NV5600 for ~13,000 miles with no effects except improved shifting.

Clunk

Hey, that's good news although Redline missed a sale with me because I couldn't find 5W-30 on the MTL bottle at the race place I shop at.

SIXSLUG

The chrysler spece'd lube isn't the same stuff they run in the nv4500. The spec'd lube is a tTexaco product which chrysler buys and repackages into their black mopar bottle and gets around 17 bucks a qt for.
The redline MTL is the correct fluid replacement for the nv5600. Its typed out correctly for the New Venture requirements, however DC won't warant the trans if you run it.
The metal flakes you see are shavings from the backing plates (synchros) and a little bit of really fine ones are normal as is some dust in the old fluid. The teeth on a new plate are shaped like a V and as they wear in they get kind of a U shape. Worn out they look like a ] and don't do anything towards meshing the gears.

Kurt