Engine/Transmission (1998.5 - 2002) Manual transmission

[CSpurgeon]

hey guys,



I keep having problems with my NV4500. First it lost a bearing at 87,000miles and now at 100,000 it is growling really bad like another bearing is getting sloppy, just at low RPM's in all gears. I pull to the max weight all the time for a living.

Wondering is the NV5600 will last better than my 5spd. Is it worth the money to convert to the 6spd or just keep fixing my 5spd????



Also, how do you think a Ford powerstoke ZF 5spd would do behind a Cummins?? Have seen and heard many great things about this german made transmission, seen one go to 600,000 miles behind a stock 5. 9L cummins conversion. Not sure if the alluminum case would handle the torque of my Bombed motor though.



Any info is apreciated.

Clint

 

[DPelletier]

Clint,

I'm no expert on the subject but;

- Will the NV-5600 last longer than the NV-4500? I would say yes as it is definitely a stronger trans. Heck its 150 lbs heavier than the 4500. Is it worth the money? Sorry, I can't answer that and probably no one can. It depends on how long your 4500 lasts next time around

- As far as the ZF goes, everthing I've read has suggested that the NV-5600 is a stronger transmission than a ZF. GM also uses the ZF behind thier Duramax and I find it interesting that thier new LLY code Duramax is rated at 590 ft lbs and is only available with the Allison. I would guess that they had concerns with the ZF at 590 ft lbs. On the other hand DC seems pretty comfortable using the NV-5600 with the new 600.

Cheers

Dave

 

[Sean Flanagan]

The guys at Standard Transmission told me that the NV5600 has its own set of problems and not worth upgrading a 4500 to a 5600. (I just looked into it) They said the 5600 is stronger, but it isn't bulletproof, and that it is very expensive to rebuild.

 

[DPelletier]

Anything mechanical has its own set of problems, but I have yet to hear of an NV-5600 power-related failure and they have been in service since 2000. It may not be worth the $'s to convert from a 4500, but I am convinced that it is the strongest transmission available in a pick-up truck. Manual or auto.



Dave

 

[PFlory]

My NV5600 with 90,000 miles has been grinding third and fourth gears for the last 15,000 miles. After about 20 miles of highway driving the grinding goes away.



_________________________________

2001 3500 cab and chassis HO 6 speed with 5800 Lb. service body and no upgrades

 

[InThinAir]

Have you changed the fluid? My NV5600 got real cranky at about 65K. Changed the fluid and much better now. Lifetime fluid my arse!!!



But as far as converting to a NV5600, unless you want to do it for fun, I would say you would be better off financially to buy a different truck with NV5600 and selling what you have and taking off your BOMBS.



Just my opinion.



---Doug

 

[bmoeller]

Looks like your truck is 2wd. Ever considered a Eaton transmission swap? Won't need to clutch while up/down shifting either. Has been done before.



http://www.roadranger.com/

 

[CSpurgeon]

Nope,

mine's a 4x4, but those Eaton transmission's look really neat!!!!!



Plan on doing a conversion on a Ford 4x2 and a Eaton would fit right in there. They sure are heavy though. The 6spd Eatons where around 350 pounds without the bellhouseing and clutch!

The 7spd would be awesome but it is 550 pounds!!

 

[TJMoor]

I have a 5600 apart right now. . I was a little shocked the intermidiate bearing , between 5ht and 6th is so small. In this trans that bearing went bad, then fluid came out the input onto the clutch. . Messy deal, lots of $$$.

I know Jeff D. at the alaska railroad , added a larger size bearing to the fifth gear in his getrag and cured a re--acuring problem there. . and I have not had the chance to try it yet, but the next getrag I do Im gonna try it. .

I find alot of ZF with bad 2nd gear syncros. . but other wise ???

Good luck

 

[TPlasek]

Sounds like if you are having bearing problems then youy may need to run a different oil in that transmission. My bearings(the lower 2) went out at 86,000. Everything else looked pretty good inside. In my opinion, if the bearing can't stay together, then the oil that lubes and cools them isn't doing its' job. I changed to synthetic Royal Purple in hopes of a better oil then the Syntorque. At 125k I changed the oil(I could actually afford to do that with this oil) and it still looked"ALMOST" as good as when I put it in. I now have 150K on the odometer with no adverse effects of not running the "appropriate" oil. I plan on once again changing it soon because I don't like to circulate the synchro matherial and bearing dust in the oil even if the oil is still good.



Just my 2 cents,

Tim

 

[DPelletier]

Tim,

Makes sense to me. I also believe that the lifetime fill is a bit of a marketing ploy. All it really means is that the transmission will likely survive without an oil change until the warranty is up on it. I plan on changing my transmission oil every 30,000 mi whether it needs it or not.



Dave

 

[DWendt]

I like the idea of a Eaton transmission. Has anyone done this yet and how severe is the modifications? I would like the 7 spd in mine as I do 99% of my driving hauling heavy loads of 24k to 28K, 300-400 miles at a time. The 6 spd just needs more gearing.

Derek