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3.73 or 4.10?

Loo

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Soon to purchase a new 2500 HD 4x4. Will pull a 5000 lb pull trailer or carry a lighter in box 8 ft camper a few times a year. Will I be happy with the 3.73? Had a 4.10 years ago on a GMC. The high rpms always bothered me. Guess I feel a 3.73 will give me a bit better mpg and engine last longer?? Big purchase, don't want to regret choosing the wrong rear-end. Thanks for any feed back.
 
Are you going to run taller tires?

My '21 PW came with 4.10s but I also swapped the 33s for 35s
Pulls a 5K trailer with no issues. Just got almost 15 MPG on a 350 mile road trip empty doing 80 MPH.
 
It's only a few hundred rpm different in the upper gears but it ups your tow rating to around 17k over 14k I believe. I went 4.10 and I'm not unhappy. Empty hiway milage is around 17 mpg if I keep it 70 or below. City driving is around 10. Combined is around 13. Not a whole lot worse than my 1500 was. I'm pulling a 28' toy hauler that weighs around 9500. Pulls great.
 
My 2500 has 3.73 gears. It also has 37s, that's how I bought it. I was a bit skeptical about how it would tow, it's been great. If ordering a truck, sure I'd order 4.10s, but I am in no way unhappy with the trucks performance. The 1st gear in the 8 speed is very low. For comparison, I've owned several Ford super duty trucks with the 6.2, and it was always recommended to get 4.30s in the axles, but the ford 6sp had a higher first gear, and combined with 4.30s, afforded a final drive the was higher than the Ram 8sp with 3.73s. Again, I always prefer the lowest ring and pinion available, but I've put almost 4000 miles on my truck in the past 6 weeks, alot towing our 18ft vnose box trailer camper conversion over many hills in new England, and it has been great. Good luck, you won't be disappointed either way.
 
You have to think about your plans for tires.....But regardless, you have to not care about gas mileage with the 6.4. Just be realistic in your usage. You probably are not going to "help" the engine much considering you could lug the engine with 3.73s and 37's. You'll probably be in tow/haul mode anyway holding gears longer...higher revs...etc. that affect mpg to the negative most times.

I ordered 4.10s with my Mega Hemi. I knew I'd put on 37's. I kinda forgot to consider that my 37's would measure out on the truck to actually be 35" exactly. Regardless, I am NOT disappointed at all. Great acceleration for a truck this size. It might even get a bit squirrely if you get all over it and the conditions are right. Real hard to get all that mass rolling. I think the wheel/tire combo is over 100lbs.

I don't think haul capacity is affected by gearing.
 
4.10s without a doubt. Don't fear the gear with a gas truck. It will also lower the strain on driveline components and transmission.
If I could've gotten it, my SRW Cummins would have 4.10's
 
My 2500 has 3.73 gears. It also has 37s, that's how I bought it. I was a bit skeptical about how it would tow, it's been great. If ordering a truck, sure I'd order 4.10s, but I am in no way unhappy with the trucks performance. The 1st gear in the 8 speed is very low. For comparison, I've owned several Ford super duty trucks with the 6.2, and it was always recommended to get 4.30s in the axles, but the ford 6sp had a higher first gear, and combined with 4.30s, afforded a final drive the was higher than the Ram 8sp with 3.73s. Again, I always prefer the lowest ring and pinion available, but I've put almost 4000 miles on my truck in the past 6 weeks, alot towing our 18ft vnose box trailer camper conversion over many hills in new England, and it has been great. Good luck, you won't be disappointed either way.
What kind of mileage do you get empty?
 
My PW has the 4.10's and just got done pulling our 5k GVW trailer 600 miles total this weekend. It pulled it great - never really felt down on power although there weren't any mountain passes to speak of. Easily maintained 65-75 MPH and acceleration was adequate even when merging onto the highway from rest stops. Fuel economy was abysmal but hey its a Hemi and I was pushing some speed. Stock tire size.
 
My 2500 has the 3.73. When towing our 4,000 lb pull trailer, it didn't even seem to know it was there. We upgraded to a 5th wheel (why I bought the 2500 & sold my 1500 - which had the 3.92) that is 9,000 lb GVWR. I recently took a trip from Albuquerque to Rapid City, SD - about 1,800 miles. The truck pulled the 5th wheel with no problem. Cruise control held speed & it hardly ever downshifted; didn't use tow haul mode either. Average mpg (hand-calculated) was 11.75 for that trip. For my needs the 3.73 works fine. It has all the towing capacity I need & for daily driving around town, I consistently see 16-17 mpg or so city, and around 20 mpg highway.

Of course it’s a diesel.
 
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Less than 10% difference either way. Doesn’t make much difference especially with a smaller trailer.

If you have plans on going up to a larger tire and you can get 4.10s then go ahead but if you find a good deal on a 3.73 truck I wouldn’t hesitate.
 
What kind of mileage do you get empty?
My camper weighs roughly 5500. Round trip towing, including over 1000 miles out to Acadia, up to moosehead lake, back trough northern New Hampshire, nets me 10.5 to 11 mpgs. Empty driving average is around 14.5, that's what I was getting from where I live to killington and back every day for a job I did there. Don't get me wrong, lower gears are great, but the 3.73s don't make my truck suck! And the truck I traded for this one was a F350 7.3 gas with 4.30s, I owned it for 7 months, loved the motor, but other things drove me crazy. Finally had the driveshaft fail, couldn't get a loaner, left the truck at the Ram dealer! With the 37s everything is still good, the zf 8sp has a great gear spread, and really low 1st gear. I definitely don't "lug" the engine. I realize the Trans must downshift sooner than with 4.10s, but it's not a big deal. Again, I'd love lower gear, cause why not!, but the truck is great as is.
 
My camper weighs roughly 5500. Round trip towing, including over 1000 miles out to Acadia, up to moosehead lake, back trough northern New Hampshire, nets me 10.5 to 11 mpgs. Empty driving average is around 14.5, that's what I was getting from where I live to killington and back every day for a job I did there. Don't get me wrong, lower gears are great, but the 3.73s don't make my truck suck! And the truck I traded for this one was a F350 7.3 gas with 4.30s, I owned it for 7 months, loved the motor, but other things drove me crazy. Finally had the driveshaft fail, couldn't get a loaner, left the truck at the Ram dealer! With the 37s everything is still good, the zf 8sp has a great gear spread, and really low 1st gear. I definitely don't "lug" the engine. I realize the Trans must downshift sooner than with 4.10s, but it's not a big deal. Again, I'd love lower gear, cause why not!, but the truck is great as is.
That sounds like what I’m getting with stock tires. I have 3.73’s also I’m getting ready for tires but can’t decide between 295/65r20 or 37x11.50r20. I will be keeping my night edition wheels. Do you have any pictures of your truck?
 
That sounds like what I’m getting with stock tires. I have 3.73’s also I’m getting ready for tires but can’t decide between 295/65r20 or 37x11.50r20. I will be keeping my night edition wheels. Do you have any pictures of your truck?
20220722_201901.jpg
Here it is, the day I drove the truck home and hooked it to our camper, towed almost 400 miles the next day, that's a true test drive.
 
Yes the 3.73 will do just fine for your current application. However the MPG difference between the two is minimal. My 2020 MegaCab with 4.10 has a tow capacity over 16k. And when not towing, the 4.10 makes the truck really peppy off the line. IMHO it is a much better driving experience.
 
Soon to purchase a new 2500 HD 4x4. Will pull a 5000 lb pull trailer or carry a lighter in box 8 ft camper a few times a year. Will I be happy with the 3.73? Had a 4.10 years ago on a GMC. The high rpms always bothered me. Guess I feel a 3.73 will give me a bit better mpg and engine last longer?? Big purchase, don't want to regret choosing the wrong rear-end. Thanks for any feed back.
For those weights a 3.73 will be fine... Shoot the 2500 will hardly be working... Heck, a 1500 would do what you are talking about easy in a 5.7 Hemi and even the 3.21 gears but the 3.92 is better... The problem with 1500's is always payload... Not a problem with a 6.4 hemi in a 2500.
 
if pulling over mountains at all 4.10s. I pull around 5000lbs regularly and with the 8 speed they are perfect for the most mountainous state in the nation but she still works plenty, definitely wouldn’t want to be geared higher.
 
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My 2500 has 3.73 gears. It also has 37s, that's how I bought it. I was a bit skeptical about how it would tow, it's been great. If ordering a truck, sure I'd order 4.10s, but I am in no way unhappy with the trucks performance. The 1st gear in the 8 speed is very low. For comparison, I've owned several Ford super duty trucks with the 6.2, and it was always recommended to get 4.30s in the axles, but the ford 6sp had a higher first gear, and combined with 4.30s, afforded a final drive the was higher than the Ram 8sp with 3.73s. Again, I always prefer the lowest ring and pinion available, but I've put almost 4000 miles on my truck in the past 6 weeks, alot towing our 18ft vnose box trailer camper conversion over many hills in new England, and it has been great. Good luck, you won't be disappointed either way.
"If ordering a truck, sure I'd order 4.10s, but I am in no way unhappy with the trucks performance."

What he said...
 
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