Shifting And The NV5600

[macdaddy]

I'd like to here from both the G56, and NV5600 people what RPM the are going up to before shifting?. Is 2600 RPM's too much between shifts?



I'm just trying to tell which is best for clutch longevity, (matching engine RPM with road speed).



Mac

 

[bcbender]

I've only had my truck a year, and I've heard that these CR 5. 9s like to turn faster sooo, I think I shift ~ 2400-2600 which puts me right at about 1600 ~ 1800 in the next gear which is peak torque... ...

Just my $0. 02

 

[TboneMan]

You guys must use a lot of fuel! The only time I shift that high is when towing. Otherwise, 2000 max.

 

[macdaddy]

So 2400 to 2600 is ok?. Does this damage anything?



I usually shift around 2100/2200 but I cant seemed to break my wife of reving the crap out of it (2400. 2600). I should be thankful i guess, it's better than short shifting the beast.



Mac

 

[Prairie Dog]

I hold off to 2400 when I'm towing but otherwise I just don't need to rev it beyond 2200.

 

[steved]

It depends on the load... empty, I shift at lower RPM (2000ish); loaded, I shift higher (2500+) to get the load moving and use the momentum to carry me to the next gear. I almost always start at a dead stop from an idle... even loaded.



It also depends on the tire and gearing... 4. 10 and stock tires make for quicker shifts at lower RPM since its not as big a drop to pick back up.

 

[macdaddy]

It depends on the load... empty, I shift at lower RPM (2000ish); loaded, I shift higher (2500+) to get the load moving and use the momentum to carry me to the next gear. I almost always start at a dead stop from an idle... even loaded.



It also depends on the tire and gearing... 4. 10 and stock tires make for quicker shifts at lower RPM since its not as big a drop to pick back up.

Ok... .



I dont have a load anymore. I'm driving the truck in my sig empty. What RPM does the dam thing any potential damage if any?



Mac

 

[AH64ID]

Empty, shift at ~1800-2000
Towing, shift at ~2200-2400, unless accelerating up a hill then ~2500

 

[steved]

From what's been stated here, lugging hard in higher gears is hard on them (just like the NV4500 5th gear nut issue is caused by)... they compare it to the effect of a jackhammer on the gears. I have 255k, so far; so good... I tow once and a while, drive mostly empty though. I don't really do anything special but find the sweet spot where I can grab the next gear without dropping too much RPM.

I want to say the most detrimental thing is fluid level... running low or not changing is bad.

 

[macdaddy]

Alright gentlemen... .



Thank you for all the info. like I said, my main concern was when my women drives the dam thing (rare) and only if ive been drinking:-laf



Mac

 

[Bob4x4]

Progressive shifting..... as the gears are higher

Hence load the rpm should be higher.

But don't worry your truck can't be hurt

By excessive rpm except down hill where

The gov can't control it

 

[macdaddy]

Oh hey Bob.....



She freaks me out the way she drives my truck. She can really drive the truck good except for the high reving shifts.



She says she goes by sound when its time to shift#@$%!



Mac

 

[Deleted member 995608]

Alright gentlemen... .



Thank you for all the info. like I said, my main concern was when my women drives the dam thing (rare) and only if ive been drinking:-laf



Mac

Same here. Haha!

 

[bcbender]

Well, I stand corrected, I shift from 2200~2300 (normally) that drops in ~ 1500. ( I checked this morning. You like me have the 4:10s and I have stock tires so she revs quite quick, thus I allow it to rev a little past 2000 otherwise all I do is shift. Should be better when I go to 285/75s from 265/70s.

Quick question I've been meening to ask, What is considered lugging? 1200? 1400? 1000?, how low should she go?



Thanks all

 

[Prairie Dog]

Well, I stand corrected, I shift from 2200~2300 (normally) that drops in ~ 1500. ( I checked this morning. You like me have the 4:10s and I have stock tires so she revs quite quick, thus I allow it to rev a little past 2000 otherwise all I do is shift. Should be better when I go to 285/75s from 265/70s.

Quick question I've been meening to ask, What is considered lugging? 1200? 1400? 1000?, how low should she go?



Thanks all

Officially, Cummins says it lugging if you can't accelerate. Thats seem a bit off to me though. We've all heard the noises it makes when your in to high of gear going slow. I just keep both of those things in mind especially when towing.

 

[HHhuntitall]

High RPM shifting won't hurt anything, though. Look at the NV4500 in the gas engines. You pretty much HAVE to get them up to 5-6k when you get going just to keep moving when you shift..... at least with the loads I haul you do. I used to have a '96 Cummins that I shifted around 4-4200 at times... . I never touched the transmission except to changed the oil and an output shaft seal once. It was running 7. 2s 1/8 miles at that point, too. I fried a clutch once, but never had any problems with the transmission, which is still running in the truck since I sold it, 300k+. The "Jackhammer" effect is worse on them than the high rpm shifts, and a high rpm shift at 30psi boost is a lot harsher than one at 18-20psi... ... and just for what it's worth, I think with the 5600 is a lot tougher than the 4500, so your U-joints will give up before it does... .

 

[macdaddy]

Good reading from all of you. My concern was more any negative impacts that over reving may have on the engine, than the NV5600.



Which while were on the subject, here's another question?



I am getting ready to do a 4K road trip with my truck empty. As you can see I have 4:10. 1's. at 70 she runs between 2200 and 2300. I usually keep her there. Can you run the CTD well into the 2500 to 2600 for hours on end with no load?



Mac

 

[steved]

In HD equipment I've been around, the engine sits for HOURS at WOT... think about a generator unit, or a drill rig.

 

[bcbender]

A friend of a friend works for Cummins and told me that they durability these things at WOT for hundreds of hrs, also that in generator / commercial applications, they start and go directly to WOT (no warm up) so you should be fine,

I ran mine last fall out to the Outer Banks and set the cruise at 70 ( for mileage reasons) 3. 5 hrs ( 360 mi) later my overhead said 20mpg; up from the normal 16. 5 ( I know they lie) but seems not too bad if you keep below 70~75. I usually tow my 11k 5er ~ 70-75, so I wouldn't worry too much.

 

[HBarlow]

Good reading from all of you. My concern was more any negative impacts that over reving may have on the engine, than the NV5600.

Which while were on the subject, here's another question?

I am getting ready to do a 4K road trip with my truck empty. As you can see I have 4:10. 1's. at 70 she runs between 2200 and 2300. I usually keep her there. Can you run the CTD well into the 2500 to 2600 for hours on end with no load?

Mac

Mac,

The simple answer to your question is the Cummins engine can't be damaged by operation in the Dodge Ram platform as long as it receives adequate periodic service with clean fuel, filters, and fluids.

I believe you can rev it up against the ECM governor fully loaded and run it like that all day without harm.