Unhappy with 1500 towing. Need Help

[ramffml]

Again… The higher the ratio, the more effort it takes to turn in the lower the ratio, the easier it is to turn. I don’t know why that’s so hard for you to understand.

There are 2 sets of gears at play; the gear in the transmission, and the rear axle ratio. Both of those combine/multiply to make your final gear ratio at the wheel. You're stuck at thinking the rear axle ratio is the only thing that matters, without understanding that the transmission can downshift and make more torque that way.

It's why I told you to ride a bike; you'd discover that you can change either the front gear or the rear gear to make more torque.

 

[RayL]

I don't know if I have suitable answer for you, but I have virtually have the same truck configuration on my 2016 Laramie, including the 3.21 which I ordered specifically. I have towed my 28' 7,000 lb loaded TT for over 12,000 miles from the east coast to the rockies and have no issues doing so. On flat ground I typically turn about 2,000 RPM in 7th gear,at 65 mph, which is fine. It downshifts easily to 6th on a hill or over overpass. A steep hill will cause it to shift to 4th and about 4,000 RPM. I don't drive with a heavy foot. I like the 3.21 because it gives me about 21.5 MPG when not towing (90% of the time), and about 10 mpg avg when towing. Made good sense to me and I'm happy.

 

[zogg]

My last truck was a Ram 3/4 with the 6.4 gas engine. It did everything I needed to to and I was pulling a 10,500 pound 5th wheel. Any more weight and I would have gone back to a diesel. It had the 3.73 gears and it still ran at a higher rpm….not like your 1500, just the nature of a gas engine. The only drawback to the 2500 was the ride when empty…was like a buckboard and bad for a daily driver. As soon as we parked the 5th wheel in a permanent campground, I traded for my 1500.
Having said that, the stability of the 2500 was superb. Brakes were awesome and most times I never had a worry about towing the rv. The difference between a 1500 and 2500 is phenomenal for towing. I always felt that I wanted more truck than I needed, rather than wished I had more truck. Good luck

 

[corneileous]

Your argument is essentially this: because the 3.92 has better torque multiplication at 0mph, it therefore means it has more torque at every MPH.

No, my argument is that a lower gear has more torque multiplication at speed, not sitting still.

This is factually incorrect.

How?? I’m really trying hard to see this from your point of view but it’s being quite difficult.

Until you understand this fact, nothing anybody writes will ever change your mind.

Again, you’re doing a **** poor job explaining your ”claim” and making it sound like it makes sense.

 

[392DevilDog]

No, my argument is that a lower gear has more torque multiplication at speed, not sitting still.

How?? I’m really trying hard to see this from your point of view but it’s being quite difficult.

Again, you’re doing a **** poor job explaining your ”claim” and making it sound like it makes sense.

I have been confused who you are conversing with...i forgot I ignored a bunch of members at one point and I am not seeing the other side. Makes sense now. Makes for less stress...lol

 

[ramffml]

No, my argument is that a lower gear has more torque multiplication at speed, not sitting still.

How?? I’m really trying hard to see this from your point of view but it’s being quite difficult.

Again, you’re doing a **** poor job explaining your ”claim” and making it sound like it makes sense.

"more torque multiplication at speed" .... versus what? What are you comparing? We need specific examples of MPH, RPM, and transmission gears.

At 0 mph, a 3.21 will have less torque in first than a 3.92 in first. This we agree on.

At 62 mph, a 3.21 is capable of providing the same torque and RPMs at the wheel as a 3.92 at 62 mph in 7th gear. This is the "problem" for you, you're thinking that the 3.92 always provides more torque at every speed, but it doesn't. It depends on the gear in the transmission. If the 3.21 is in 4th or 5th, it's making more power than the 3.92. If it's in 6th, it's making the same power.

 

[dhay13]

I have a 2020 Bighorn with the 3.92 rear end and tow the same 2600 RB trailer. My payload is quite a bit higher though-1721. I have not been out of the SE, but have towed through the north Ga and smoky mountains with no issues. I use the same Equalizer 4 point WDH. I have been towing RVs for three years now. My truck runs mostly 6th or 7th gear on the interstate in Florida, typically around 2500 rpm. I usually stay around 65mph. I have found the combo to be easy to tow, very little sway unless the wind is high. Most passing big rigs produce little effect. I suspect you could load your trailer and improve your towing experience with some adjustments to the hitch. But you are in trouble with payload. 900 pounds is pretty typical tongue weight for the 2600 Rb. Many owners end up over 1000. Mine is usually 850-900 for a short camping load. I attached my last CAT ticket before our fall trip to Asheville, NC Last year. That was loaded for a ten day trip just as a data point. My opinion would be that you could make it work, but that payload issue will always be on your mind. You unfortunately have the wrong truck for this trailer. I had to trade a nine month old truck for this same reason. Stayed with a 1500 as a daily driver, but the Bighorn max tow package has been much more well suited than a limited or longhorn. I would have bought a 2500 gasser if I was doing it all over again, but I am happy with my current combo all things considered. Good luck to you, it is an agonizing decision.

I would be very surprised if your payload was 1700lbs. The only 1500's I have seen with that high of a payload was a stripped down Tradesman. Check your yellow door sticker

 

[ramffml]

I would be very surprised if your payload was 1700lbs. The only 1500's I have seen with that high of a payload was a stripped down Tradesman. Check your yellow door sticker

I have a level 2 big horn, 1750 pounds of payload here according to the sticker, that's with 4x4 and factory bedliner as well. The trick seems to be: no etorque, no sunroof, no ram boxes.

 

[corneileous]

There are 2 sets of gears at play; the gear in the transmission, and the rear axle ratio. Both of those combine/multiply to make your final gear ratio at the wheel. You're stuck at thinking the rear axle ratio is the only thing that matters, without understanding that the transmission can downshift and make more torque that way.

It's why I told you to ride a bike; you'd discover that you can change either the front gear or the rear gear to make more torque.

Your final gear ratio is what it is that’s stamped on the gears and the only thing really that can change that is when you start changing your tires size either too small or too big.

Sigh…. These trucks aren’t like bicycles, man.

 

[corneileous]

"more torque multiplication at speed" .... versus what? What are you comparing? We need specific examples of MPH, RPM, and transmission gears.

No “we” don’t but you seem to.

At 0 mph, a 3.21 will have less torque in first than a 3.92 in first. This we agree on.

At 62 mph, a 3.21 is capable of providing the same torque and RPMs at the wheel as a 3.92 at 62 mph in 7th gear. This is the "problem" for you, you're thinking that the 3.92 always provides more torque at every speed, but it doesn't. It depends on the gear in the transmission. If the 3.21 is in 4th or 5th, it's making more power than the 3.92. If it's in 6th, it's making the same power.

Yeah because you’re having to use a lower gear in your trans and rev the crap out of your motor to compensate….Lol.

 

[ramffml]

Your final gear ratio is what it is that’s stamped on the gears and the only thing really that can change that is when you start changing your tires size either too small or too big.

Sigh…. These trucks aren’t like bicycles, man.

In that both trucks and bikes have gears in two spots? A front set over your legs (transmission) and a rear set on the back tire (rear axles)? Yes, they most definitely are the same that way.

How the math works: you take the gear at the front, multiply it by the gear in use at the back, and end up with a gear ratio. You can change either the front (up/downshift) or the rear (swap a 3.21 for a 3.92) and recalculate; you will end up with the same final value in many cases if the gears have the right values.

 

[corneileous]

I have been confused who you are conversing with...i forgot I ignored a bunch of members at one point and I am not seeing the other side. Makes sense now. Makes for less stress...lol

Egh, I find it pointless to ignore people on here.

 

[ramffml]

No “we” don’t but you seem to.

Yeah because you’re having to use a lower gear in your trans and rev the crap out of your motor to compensate….Lol.

You're just writing stuff without any numbers or math to back your claims. Its no wonder you don't get it.



Lets do the math. A 3.21 in 6th gear has a gear ratio of 3.21. A 3.92 in 7th has a 3.2144 gear ratio.

Fact #1: When the 3.21 is in 6th gear, the engine RPMs and mph will be identical to the 3.92 in 7th gear.

Fact #2 Since the engine RPMs are the same, and the mph are the same, so is the torque/power.

Please point out which of those 2 facts you don't accept as true.

 

[yoda]

I read most of the replies in this thread,

To the OP.

2700 RPM towing your camper is perfectly fine and to be expected, if your truck handles the trailer braking, no swaying etc in my opinion there is no need to get a 2500.

If you really dislike the rpms, the answer would be a 2500 Cummins, which seems like overkill in my opinion.

I went from a 2500 Cummins to 3500 6.4 towing a 30 foot travel trailer and was really worried I would regret it. I have been very pleased with the 6.4, but also knew going in it was going to rev more.

In your case going to a 2500 6.4 may be a little better RPM wise but not much, and with the 8 speed don't fret the gear ratio thing you have plenty of gears in the transmission, let it do its thing, if it hunts up and down to much for your liking, lock it in a lower gear when necessary (lots of hills etc) your not going to hurt your truck, let it rev. turn up the radio a little

 

[yoda]

"more torque multiplication at speed" .... versus what? What are you comparing? We need specific examples of MPH, RPM, and transmission gears.

At 0 mph, a 3.21 will have less torque in first than a 3.92 in first. This we agree on.

At 62 mph, a 3.21 is capable of providing the same torque and RPMs at the wheel as a 3.92 at 62 mph in 7th gear. This is the "problem" for you, you're thinking that the 3.92 always provides more torque at every speed, but it doesn't. It depends on the gear in the transmission. If the 3.21 is in 4th or 5th, it's making more power than the 3.92. If it's in 6th, it's making the same power.

Not to get in the middle of a ******* contest, but you are correct.

Torque multiplication can happen in the rear end or in the transmission, really makes no difference where

With the old 3 and 4 speed autos there was much bigger ratio gap in the trans between gears and lower rear end gears helped.

With these 8 speeds, there are plenty of transmission ratios to let the engine rev to where it needs to when towing.

Maybe the guy is comparing it to the old 727 days

 

[corneileous]

You're just writing stuff without any numbers or math to back your claims. Its no wonder you don't get it.

View attachment 487894

Lets do the math. A 3.21 in 6th gear has a gear ratio of 3.21. A 3.92 in 7th has a 3.2144 gear ratio.

Fact #1: When the 3.21 is in 6th gear, the engine RPMs and mph will be identical to the 3.92 in 7th gear.

Fact #2 Since the engine RPMs are the same, and the mph are the same, so is the torque/power.

Please point out which of those 2 facts you don't accept as true.

OK so, after thinking about it, let me put it this way; the eight speed transmission is the only reason why you even have an argument in the first place but still, the 392 gear is much better for towing and the 321 is meant for people who don’t tow lot or at all or very light and want a 400 horse V-8 to get around 20 miles to the gallon when they’re not towing anything oh so don’t act like the 321 is all that and a sack of peanuts and pretty much discredits the 392.

 

[corneileous]

Not to get in the middle of a ******* contest, but you are correct.

For one it’s not a urinating contest… two, you already did get in the middle of it which is fine and three, he may be correct on certain things but just merely explaining that the transmission has to go to a lower gear to compensate for the higher rear end only proves that you can have your cake and eat it too if you don’t tow that much and still get good mileage when you’re not towing.

Torque multiplication can happen in the rear end or in the transmission, really makes no difference where

OK so then just like I asked the other guy; if the eight speed transmission makes up for the torque magnification then why is it the trucks with the higher rear end gears don’t have the full 10,000+ trailer towing capacity?

With the old 3 and 4 speed autos there was much bigger ratio gap in the trans between gears and lower rear end gears helped.

Yet the lower rear end gear still help even with the eight speed transmission.

With these 8 speeds, there are plenty of transmission ratios to let the engine rev to where it needs to when towing.

So then are you saying the ratio of the rear end gears just doesn’t matter at all except for how much towing the user will be using the truck for?

Maybe the guy is comparing it to the old 727 days

Um, no.

 

[ramffml]

OK so, after thinking about it, let me put it this way; the eight speed transmission is the only reason why you even have an argument in the first place but still, the 392 gear is much better for towing and the 321 is meant for people who don’t tow lot or at all or very light and want a 400 horse V-8 to get around 20 miles to the gallon when they’re not towing anything oh so don’t act like the 321 is all that and a sack of peanuts and pretty much discredits the 392.

I'm not discrediting the 3.92. See this post:

Unhappy with 1500 towing. Need Help

So then tell us…. If what you say is so true It's not "if", it's not my opinion, it's a mathematical certainty. The two trucks have a different tow rating on paper, due to the 3.92 being able to accelerate faster from a dead stop. Two of the J2807 tow rating tests deal specifically with 0...

www.ramforum.com

My entire argument in this thread has been this: the 3.21 and the 3.92 will give you identical towing results at 62 mph (which is what the OP talked about in the very first post) so for the OP, getting a 3.92 will not change or help him at 62 mph.

 

[airrecon]

Today I picked up my Grand Design Imagine 2600rb. I’m a first time RV’r. I was incredibly disappointed as to how the 75 mile ride home went. It was all expressway and mostly flat (It is Illinois) and my truck rarely made it out of 5th gear! My truck is a 2020 Longhorn with a towing capacity of 8120 lbs with a max payload of 1770lbs. 5.7 Hemi with e torque and 3:21 gears. 8HP75 transmission. The trailer weighs 5800lbs dry and since it was new there was nothing loaded in the trailer yet. I used a weight distributing hitch, Equal-I-Zer brand.

At 62mph (with everyone passing me) in a 70mph limit, the truck was revving at 2700rpm’s in 5th gear. I did use tow haul to enter the expressway but turned it off once speed increased. There were a few times on a slight downgrade that the transmission shifted into 6th gear and one time coasting it briefly went into 7th gear but it was brief. The Electronic Range Select (ERS) was not engaged. Upshifting and downshifting were fine.
I have never had any problems mechanically with this truck and up until today (with exception of some Rambox latch problems) I have loved this Longhorn. The 5.7 has always been a good runner for me.

So, please, I’m looking for suggestions from experienced RV’rs as to what is going on here? Is the 3:21 gear the culprit? Did Ram overstate the towing capacity? Just because the truck’s frame and axles can physically carry the weight, maybe the transmission isn’t equipped for towing. I’m leery to add the usual weight of daily necessities for a trailer trip let alone hitting any hilly areas. After at $70K for a truck and another $40K for the trailer it quite disappointing. I’m desperately seeking experienced analyses.
Thanks in advance,
Hank

First of all, always use tow/haul. That's what it's for.You have a smart transmission that will pick the right gear, use it and forget about gears. I have a 19' Longhorn with air suspension, 3.92 rear end. On long trips I average 8MPG with a 7500# trailer. Sometimes up to 10, sometimes 7. This is towing at least 10,000 miles on flat I-10 and mountains. Once with a strong head wind headed west on I-10 got 4mpg. I drive 65mph on the interstates and other good roads. Other trailers pass me at much higher speeds, but I feel that is the comfortable one for my rig. I may add I spent a few years as an amatuer sprint and sports car racer so I'm not an overly conservative driver normally, and use the heck out of a radar detector when not towing.

 

[airrecon]

As mentioned by another. 62 mph is a safe speed to be towing at. And yea...the Hemi needs RPM. At 2700 RPM you are basically lugging it.

You picked a great truck for what you are doing...i just think your understanding of it may have been off.

Agree. A better gear ratio would help but contrary to some other comments he has all the engine he needs. Either way on interstates he can keep at 65MPH on long mountain climbs.