Left in the dust

[Thall]

Please help me out with some sensible knowledge and advice. I have a 2018 3500 Dually with the 6.4. It has the 6 speed auto transmission and 3.73 gears.

I have a terrible time pulling my 30’ stock trailer. The trailer is 10,000lbs empty. When it is loaded i really struggle with torque and getting it up to speed.

Does anyone have any recommendations or wisdom to share to overcome these issues?

 

[MADDOG]

Well, my first thought is get a Cummins.

But since you are probably not wanting to trade in a fairly new truck you can improve towing performance with:

1. A cold air intake
2. A programmer & blank PCM (needed for newer trucks as your original is encrypted)
3. A custom tune
4. A free flowing exhaust. All that really requires is a muffler swap vs. doing the whole system.
5. 4.10 gears

I did 1 through 4 to my 2014 2500 with the 6.4L HEMI and those mods really improved torque, HP and driveability.

Good luck!

 

[Thall]

Thanks for the tips. This truck has 4000 miles on it. We have a 2019 2500 with the same engine. It seems to have a lot more power than the 2018.

Which upgrades if I was to choose 1 or 2 of them would you recommend for the most change?

 

[Bldrinker]

Thanks for the tips. This truck has 4000 miles on it. We have a 2019 2500 with the same engine. It seems to have a lot more power than the 2018.

Which upgrades if I was to choose 1 or 2 of them would you recommend for the most change?

your 2019 is an 8speed that’s why you can tell a big difference.

do not change your gears from 3:73 to 4:10 that is not a big difference. . Go 4:56 or 4:88.

for the cost of all the upgrades mentioned above plus gears it would be cheaper to just buy a diesel.

 

[MADDOG]

Thanks for the tips. This truck has 4000 miles on it. We have a 2019 2500 with the same engine. It seems to have a lot more power than the 2018.

Which upgrades if I was to choose 1 or 2 of them would you recommend for the most change?

Well, the intake, exhaust & programming all work together as a system. It's sort of like a 3-legged stool. Take out one leg and it don't work as a stool.

But if you are going to start somewhere the programmer and custom tune would make the most difference. But without more air in and more air out you won't be able to realize the true benefit of those mods.

Thinking on the gear issue my personal preference would not be to go as high as was otherwise recommended simply because you still gotta drive it at highway speeds and the engine RPMs will rise quite a bit.

What gears are in the 2019? Just curious as both trucks should feel about the same if they are both 3.73 gear equipped.

 

[Mountaineer83]

The transmission gearing in the 6 speed is the issue. The 1st gear is a 3.23 vs the 1st gear on the 2019 at 4.71. That alone will make a huge difference when starting out pulling a heavy load.

Depending upon your overall tire diameter, I'd say a 4.56 would be optimal. I have a 4.10 equipped 2500 and at 70 in 6th, I'm only running like 180p rpm. I am on 34" tires, so even with a 4.88 rear gear, I would only be turning 2100 rpms. The peak torque on the 6.4 is at 4000 rpm. So it lugs at lower rpm, unlike a diesel. There is a gentleman on here who has a dually and added 4.44 gears and said it made a big difference while towing.

Going 3.73 rear to 4.10 is not worth the money spent. If your tires on your dually would be 32" tires (just an example), then a 4.56 would put you in a good place rpm wise. Most guys who go lower on gears have actually seen an increase in mpg.


I would reccomend starting with a gear swap just because it is going to be helpful getting a heavy load going. It will also put you in a better crushing rpm once up to speed. Expect anywhere from $2k to $3k for a swap if 4x4, less for a two wheel drive truck.

 

[dhay13]

Agreed on the gear change. Go to a 4.56 or so. Will help alot. 4.10's won't make a huge difference

 

[Bldrinker]

Well, the intake, exhaust & programming all work together as a system. It's sort of like a 3-legged stool. Take out one leg and it don't work as a stool.

But if you are going to start somewhere the programmer and custom tune would make the most difference. But without more air in and more air out you won't be able to realize the true benefit of those mods.

Thinking on the gear issue my personal preference would not be to go as high as was otherwise recommended simply because you still gotta drive it at highway speeds and the engine RPMs will rise quite a bit.

What gears are in the 2019? Just curious as both trucks should feel about the same if they are both 3.73 gear equipped.

How would the 2019 feel about the same as a 2018 if both have 3:73 gears?
2nd gear in the 2019 is almost the same as the 2018. That makes for night and day difference.

Going from a 3:73 to a 4:10 is a small change. And will cost $2500-3000.

Would really suck to spend that kind of money and barely feel the difference.

keep in mind, allot of guys on here are very unhappy with their stock 4:10.

Go 4:56 or 4:88.

I’m about to buy a Toyhauler that is over 10,000lb empty. If it has hard time on hills I will likely go 4:88. I can always add 1” or 2” taller tires if it hurts highway rpm to badly.

 

[GsRAM]

As said, gears, gears, gears!

Those will be the biggest bang for your buck and will give you ther biggest seat of the pants difference at the weights your pulling. Also, as said, go straight to a 4.56 or 4.88 gear. There's not enough difference between 73s and 10s to justify the 3k cost if your 4x4.

Honestly, if your trailer is 10k empty, what is your loaded weight? The 6.4 is a beast but your asking an awful lot of it. I always felt that north of 10k on a regular basis was Cummins territory. If your over 15k loaded weight, give serious thought to the 4.88s because your dually is heavy to begin with.

Good luck.

 

[jvbuttex]

So from what you said above, the Hemi really wakes up with free'r breathing. Intake/exhaust really help on a 5.7 also? I too will start towing a TT, not quite same weight, only 5k lb. Wont be regular basis, maybe 3 ~4x a year But more help is always better.

 

[MADDOG]

How would the 2019 feel about the same as a 2018 if both have 3:73 gears?
2nd gear in the 2019 is almost the same as the 2018. That makes for night and day difference.

So educate me.

If they have the same differential gears and "2nd gear in the 2019 is almost the same as the 2018", how does that make for a "night and day difference" if the gearing is the same?

 

[Mountaineer83]

So educate me.

If they have the same differential gears and "2nd gear in the 2019 is almost the same as the 2018", how does that make for a "night and day difference" if the gearing is the same?

I think he meant to say that 2nd on the new 8 speed in the 2019 is the same as 1st on the older 6 speed. I know from having one that when towing heavy, the 1st gear needs to be a lot lower to get the load moving. Even the Super Duty 6 speed has a 4.17 first gear.

The 66RFE 6 speed in yhe 2018 back HD Rams has the exact same gear set as the Cummins trucks, making it too high of gearing for the rpm happy Hemi. It needed lower gearing for the 6.4 trucks, but my thoughts are that FCA didnt think the 6.4 powered trucks would sell like they did, so they didnt develop a completely new transmission the first time around.

Now the 2019+ trucks have the all new 8 speed mated to the 6.4 Hemi. And from what I've read, it makes a huge difference.

 

[GsRAM]

So from what you said above, the Hemi really wakes up with free'r breathing. Intake/exhaust really help on a 5.7 also? I too will start towing a TT, not quite same weight, only 5k lb. Wont be regular basis, maybe 3 ~4x a year But more help is always better.

An engine is basically a large air pump. More air in, more air out in simple terms usually means more power. But again, gears will be the biggest bang for your buck in terms of real world towing performance difference. If you already have the optimal gear, then yes, heads, cam, intake, exhaust will help

 

[jvbuttex]

GsRAM, thanks for your input ,yes I know all about engines and air / fuel flow. However some engines are well designed for optimal performance in factory. So there is not many mods out there that will give a big bang for the buck. Only small tweaks here and there. Case in point. I have talked to many shops about my MB there is little to no mods because from factory the engine was already optimal. So, having said that, yes intake / cam / exhaust will help, but at what cost will be the big question. I'm leaning towards gears first. will have to make more calls to HP shops and get hard numbers about cam. Dont need a drag truck, just a puller. Yes I also know a Cummins is better for towing. Just dont want the payment.

 

[Ratket]

Gears gears gears..

sounds like it is your dedicated tow vehicle being a dually and all.

I would say 4.88”s at a minimum or 5:13”s.

now you will lose top end but as long as you tow under 70, that thing should hum just fine in 3rd/4th gear pulling 10k all day long. The lower gear will also help you get up to speed. Mileage shouldn’t be to adversely affected, I’d even wager it will get better mileage as you won’t be dumping fuel at a never ending rate trying to produce power. The truck will get to speed and hold speed since the gearing will be more in favor. Remember it’s a dually, you got a lot more rotational mass back there, so the more you can help get it rolling and keep it rolling the better.

mai again my 2 cents is gears. I fear with 4:56 you will still be wanting shorter gears. There are members on here that have gone 456/488 and I believe one guy went 5:13”s- you may be better off starting a new thread calling upon advise from guys who have re geared their 6.4 HD”s.

 

[Gero]

Definitely would try and regear it or upgrade to the 5th generation with the 8spd. Its unfortunate that its paired with the 6spd. Have a look at tfl's video with the ram 2500 6.4 going up the ike. It had a hard time getting up there despite having kore power than its direct competition (GM's 6L)

 

[JohnnyMac]

You could skip the gears and just go with smaller wheels/tires. That'll gear it down for you....

 

[GsRAM]

Lol, one can do a lot with photoshop or similar programs these days. Zoom in on the wheels, they appear to be 5 lug and not 8 lug. Hahahaha....that is too funny though..

 

[gofishn]

... Just dont want the payment.

...and that is why you are here, asking these questions.

Power cost money.
Pay for it, up front, when you buy the right Rig for the Job that needs done or
later, trying to tweak a lesser equipped rig.

Usually much cheaper to get it already equipped than upgrading it yourself.
Either way, power will get paid for, reason a Hellcat costs more than a Prius

 

[jvbuttex]

...and that is why you are here, asking these questions.

Power cost money.
Pay for it, up front, when you buy the right Rig for the Job that needs done or
later, trying to tweak a lesser equipped rig.

Usually much cheaper to get it already equipped than upgrading it yourself.
Either way, power will get paid for, reason a Hellcat costs more than a Prius

yes so true... i have been upgrading my truck and the parts im replacing or adding to i am paying full price. Problem is, some have bought a truck for what they needed at the time. 3yr ago, I had NOOOOO plans for a TT... now times change...