"Tow Haul" button question.

[blade]

i saw on truck tech (motortrend tv). the guy was drag racing ram 3500 diesel and he said he used it cause it locks up the torque convertor. i don't know if thats true or even exactly what that means. i think it locks engine and tranny input shaft in a 1:1 ratio.

but in my ram 1500 5.7 its makes my truck faster in the 660ft and zero to 60mph track times depending on what tune i am running.

definitely helps w engine braking. I'm sure would b useful in mountains

 

[marks146]

Obviously I'd want to use this when I tow my boat, but would it be necessary to use it when hauling my ATV on a small utility trailer? Maybe 1000 pounds total.

You can use the tow/haul mode any time you want the trans to hold lower gears a little longer or to increase the engine holdback when in the mountains. I use it all the time when I'm in the mountains. It helps keep my engine RPM's up to increase torque, and to help hold the truck back when descending hills rather than riding the brakes.

It's useful for more than towing.

 

[pacofortacos]

Tow/Haul Mode
When driving in hilly areas, towing a trailer, or carrying a heavy load and frequent transmission shifting occurs, pressing the TOW/HAUL switch to select TOW/HAUL mode will improve performance and reduce the potential for transmission overheating or failuredue to excessive shifting. When operating in TOW/HAUL mode, transmission upshifts are delayed, 8th gear overdrive is prohibited, the Multiple Displacement System (MDS) system is prohibited from cylinder deactivation, and the transmission will automaticallydownshift (for engine braking) during steady braking maneuvers

The stuff in bold is not true for some if not most 8 speeds. My 2016 1500 definitely does NOT stop MDS or 8th gear from happening when in tow/haul.

 

[Ratket]

^ Thats a false excerpt from some where. Only gear selection disables MDs.

 

[Fitz-0518]

Paco my 2018 2500 6.4 66RFE. Tow haul only allows MDS to engage. BUT,,,,not very often if you are using the accelerator often. i.e. hills with trans shifting. In ours the only thing that disables MDS is gear select 6. We set both when towing. BUT,,I have read on this forum that other trans, engines and years are different. Fitz

 

[pacofortacos]

Paco my 2018 2500 6.4 66RFE. Tow haul only allows MDS to engage. BUT,,,,not very often if you are using the accelerator often. i.e. hills with trans shifting. In ours the only thing that disables MDS is gear select 6. We set both when towing. BUT,,I have read on this forum that other trans, engines and years are different. Fitz

I think the programming has changed over the years and that might be some of the confusion.
Now we have a reference for the newer 2500 6 speed version too

 

[boblonben]

Obviously I'd want to use this when I tow my boat, but would it be necessary to use it when hauling my ATV on a small utility trailer? Maybe 1000 pounds total.

Nope, generally find the trans and motor get best use of the tow/haul for things above 1800 pounds or so, below that there just isn't enough weight. But doesn't mean you can't use it. It just changes the transmission shift points to rpm. Just haul;ed a 23001 Dakota Crew/quad cab and was curious about the difference in trans performance betgween regular and tow/haul. Live in south Texas so not many real hills. TGruck did just fine in both but did seem 'smoother' in the tow/haul mode, Down the raod constant speed even in tow/haul still got to 8th and about 1800 rpm at 65, that equates to about 19 mpg towing 5200 pounds, not to bad.

 

[boblonben]

around

Nope, generally find the trans and motor get best use of the tow/haul for things above 1800 pounds or so, below that there just isn't enough weight. But doesn't mean you can't use it. It just changes the transmission shift points to rpm. Just hauled a 23001 Dakota Crew/quad cab and was curious about the difference in trans performance between regular and tow/haul. Live in south Texas so not many real hills. Truck did just fine in both but did seem 'smoother' in the tow/haul mode, Down the road constant speed even in tow/haul still got to 8th and about 1800 rpm at 65, that equates to about 19 mpg towing 5200 pounds, not to bad.

 

[Retiring Don]

It would be nice if we had a RAM engineer who is involved in the ECM programming who could provide a definitive answer, but next time I'm pulling my travel trailer on an extended trip I'm going to pay close attention to the engine RPMs and upshifts while towing and compare them to unladen driving. All I know at this point is that my gas mileage goes from 20 highway mpg when not towing and 11.5 mpg when I've got my travel trailer behind.

 

[JSMITH8505]

Below 4500 lbs- The truck will tell you. Just listen.
If you get to operating speed and it shifts more than 3-4 times per mile, you probably need tow/haul on.


Above 4500 lbs: Put it in tow haul unless you're driving across Kansas or Nebraska and NOT using cruise control.

Also- if you're driving less than 60 mph, You're too close to the 5th to 6th shift point and it will bounce between both gears too much. Go ahead and save the shifts, put tow haul on

 

[JPT]

Simple solution... If you are towing, or have a heavy load in your truck, just use the switch. It won't hurt anything but mpg. The alternative is, it could (I have no proof) add unnecessary wear and tear on your transmission.

 

[Walt2137]

On my 17 Ram if i turn on the tow haul and take off the trans will only go to gear 7 and it will chang gears at about 1000 rpm higher than no tow haul.

 

[RoadRamblerNJ]

Doesn't Tow/Haul keep the transmission out of top gear (6 speed /2500/ 6.4 Hemi)?
And doesnt T/H deactivate cylinder cut off?

Yes. No 6th gear in tow/haul. However, in the manual gear limit mode, You will still have 6 gears if tow/haul is not on. This also stops the MDS from activating. Such an annoying and really useless "feature".

 

[RoadRamblerNJ]

The stuff in bold is not true for some if not most 8 speeds. My 2016 1500 definitely does NOT stop MDS or 8th gear from happening when in tow/haul.

No, you are correct. Shifting down (-) from "D" to the manual +/- mode stops MDS from activating. Tow/haul has nothing to do with MDS. I use both, always. I drive agressively and I like how the truck operates with traction ctrl off and manually limiting my top gear. I typically engage Tow /haul mode too. Oh yeah, PC is set to Sport +3 also. It's just how I like it to be set up.

 

[Rbertalotto]

Sure wish Tow/Haul automatically activated when you hook up a trailer if the truck has the trailer brake control feature. I usually forget vto turn it back on after a stop.

 

[PaulTGarrett]

Simple solution... If you are towing, or have a heavy load in your truck, just use the switch. It won't hurt anything but mpg. The alternative is, it could (I have no proof) add unnecessary wear and tear on your transmission.

I never believed the "if you're towing, put the transmission in tow mode" story line... Until I went through the second transmission in my '98 RAM. The second time the overdrive clutch burned out, the entire transmission was junk, not repairable. The guy in the transmission shop (NOT a dealer shop) told me flat out it was because I was towing my boat around town with the overdrive on. Told me he didn't even need to ask me if that's what I was doing, he could tell because of the damage.

I have a hard fast rule now, if something is hooked to the trailer hitch, the truck is in tow mode. Period. Transmissions cost too damn much money just because I don't want to punch a little button on the dash.

 

[GsRAM]

I never believed the "if you're towing, put the transmission in tow mode" story line... Until I went through the second transmission in my '98 RAM. The second time the overdrive clutch burned out, the entire transmission was junk, not repairable. The guy in the transmission shop (NOT a dealer shop) told me flat out it was because I was towing my boat around town with the overdrive on. Told me he didn't even need to ask me if that's what I was doing, he could tell because of the damage.

I have a hard fast rule now, if something is hooked to the trailer hitch, the truck is in tow mode. Period. Transmissions cost too damn much money just because I don't want to punch a little button on the dash.

100% agree Paul. I use tow/haul anytime i have a trailer hooked up. Doesn't matter how heavy it is. The added benefits of extended shift points and holding gears longer for added engine braking is worth it alone.

Towing is hard on stuff. Thats why I'm very diligent about maintenance on my truck. Take care of 'em and they'll live awhile... If you don't...be ready to break out that wallet! The tow/haul helps minimize engine lugging with weight on, also very important to the longevity of drivetrain components....just my .02 though...ymmv

 

[RoadRamblerNJ]

Also, I found what appears to be a small "glitch" [sarcasm]. This has happened to me 5 or 6 times since buying my '17 Tradesman CCLB 6.4 4x4 4.10s. (Mostly while in rush hour, North Jersey, crazy train traffic).

While driving "aggressively" [emoji38] with.....
1. Traction control OFF
2. +/- gear set to 5 (No MDS active)
3. Tow/Haul mode ON

While driving at speed (50 mph+), in my attempt to have the trans downshift one gear because you see an opportunity for a "move" you want to put on a guy, you very quickly mash the gas pedal 1 or 2 times. ( picture Grave Digger setting up his next jump. That throttle sound) The truck immediately downshifts into 2nd! Tach goes to about 5500+ rpm! Still doing 50 or 60 or whatever mph, let off the gas with zero effect, look at the "gear #" and it still says 5. Push "+" and instead of seeing 5 become 6, it now reads 3, indicating it was set on 2! Meanwhile, still SCREAMING along because the damn truck is in 2nd gear, you're attempting a three lane Emergency landing to the shoulder of the highway. (Jersey guys love it when you do that, they tell you how much with their middle fingers)! FINALLY, after anywhere from 15 to 30 seconds! it will upshift 3 or 4 gears into 5th or 6th and the pucker factor is over.

Dealership on Rt 23 in Sussex County, NJ says my transmission is "learning how I drive". Yeah. Let me translate that...either they don't have a clue, or, they DO have a clue and don't want to say it it out loud.

Anybody else ever have the pleasure?

 

[muddy12]

..................Push "+" and instead of seeing 5 become 6, it now reads 3, indicating it was set on 2! Meanwhile, still SCREAMING along because the damn truck is in 2nd gear, you're attempting.......

It wasn’t “set” to 2nd, it just happened to still be in 2nd when you hit the +button. In very basic terms, pressing +or- shifts the trans up or down one gear from which ever gear it is currently in.

Example, you have it set to 5th, which as you know, still let’s the trans shift through all the gears, it just locks out 6th(and higher for the 8 speed guys). So let’s assume you have selected 5th, but you come to a stop. While stopped the trans will shift down to 1st. You start to pull away and the trans shifts up normally, 2nd, 3rd, and then you hit the + button. When you hit the button, the display will show 4th(even though you previously selected5th) because at that moment the trans was only in 3rd.


Sent from my iPhone using Tapatalk

 

[RoadRamblerNJ]

It wasn’t “set” to 2nd, it just happened to still be in 2nd when you hit the +button. In very basic terms, pressing +or- shifts the trans up or down one gear from which ever gear it is currently in.

Example, you have it set to 5th, which as you know, still let’s the trans shift through all the gears, it just locks out 6th(and higher for the 8 speed guys). So let’s assume you have selected 5th, but you come to a stop. While stopped the trans will shift down to 1st. You start to pull away and the trans shifts up normally, 2nd, 3rd, and then you hit the + button. When you hit the button, the display will show 4th(even though you previously selected5th) because at that moment the trans was only in 3rd.


Sent from my iPhone using Tapatalk

OK, understood. My concern is not what was displayed. My concern is my truck, while driving maybe 60 mph, (NOT taking off from a stop) shifted from 5th gear into 2nd gear, damn near redlining the tach! And, it stayed there! Would not upshift, even with zero throttle and the displayed maximum gear setting still 5. And when I say "for 15 to 30 seconds", I'm not exagerating. It seemed like forever! If it had only happened once, exageration would be an expected thing. It really does last that long! Then, magically figures out 2nd gear at 5800 rpms with no throttle input is wrong. Boom, boom, boom, 2-3, 3-4, 4-5 upshifts occur in a matter of several seconds. No way can anyone say this is normal, right, acceptable etc. just because the throttle got stabbed.