MPG which is better same setup 22 Ram 3500 6.7 diesel SO 3.73 SRW 68rfe VS 22 Ram 3500 6.7 diesel HO 3.73 SRW Aisin

[hylasw]

Here is a question I am trying to get answered researched it and asked dealers and gotten mixed reviews. Same Setup on each truck 2022 Ram 2500 6.7 Diesel SO 3.73 SRW 68RFE vs 2022 Ram 3500 6.7 diesel HO 3.73 SRW Aisin which truck gets better MPG

I have asked Ram dealers some say no difference, some same SO will get better MPG, and some say HO will get better MPG ?
Here is a video of someone with a HO Saying he gets horrible MPG VS his SO but looks like he is using a tuner, plus he has a 4.10 ?

Does anyone have both trucks and seen what the MPG does between both trucks ?

 

[thecastle]

There is a long thread about this already. Bottom line is they're generally going to be similar. There isn't a lot of difference in the work (hp) the two engines produce. So fuel economy differences will be situational. The HO with some trailers might be able to stay in a taller gear than the SO at the same speed, so the HO looses less economy due low RPMS and lower rotational friction. But the HO has a lower compression ration, so under light load conditions it will have a lower thermal efficiency than the SO. Of course the HO may suffer less pumping losses due to a lower restriction bigger turbo, and plumbing differences to reach that 430hp. So less pumping losses mean better fuel economy. So which one does better, is going to depend on your situation, driving habits, load and etc. I would in general say the economy differences don't seem to be large between the SO/HO. Tuning can really lower your economy, especially if you have a smokey tune, as at that point your dumping too much fuel into the engine that can't be burned, and your money is flying out the exhaust in the form of unburnt fuel (smoke). Of course some tunes can improve fuel economy. Most tuners buy an off the shelf tune and toy with it thinking they can make it better, but most "tuner" shops are mechanics and not software engineers, who wrote the tune in the 1st place.

 

[The1adman]

Not an exact comparison, but my 2017 3500 SRW SO got 1-3 MPG better than my 21 3500 SRW HO in about every situation. The biggest MPG difference is when towing.

 

[MtnRider]

SO will get slighter better from all the data I have seen and don't bother asking dealers, they honestly have no clue. Any thing they tell you is going to be a guess on their part. (or aimed at selling you one of another)

 

[John Jensen]

If you can believe what owners report, the SOs definitely get much better mileage than my HO when not towing. Don't know about that when towing.

 

[hylasw]

SO you are saying you see that 1-3 MPG Better in the SO When towing ? Reason I am asking is I am going to be purchasing a new 2022 Ram 3500 I am only towing 10,000 lbs. 5th wheel with it 80-90% of the time I am using the truck I don't really think I need the HO and extra power but want the best MPG possible

Not an exact comparison, but my 2017 3500 SRW SO got 1-3 MPG better than my 21 3500 SRW HO in about every situation. The biggest MPG difference is when towing

 

[Brutal_HO]

SO you are saying you see that 1-3 MPG Better in the SO When towing ? Reason I am asking is I am going to be purchasing a new 2022 Ram 3500 I am only towing 10,000 lbs. 5th wheel with it 80-90% of the time I am using the truck I don't really think I need the HO and extra power but want the best MPG possible

Not that the Aisin is bad IMHO, but you might experience better mannered trans shifting in the SO/68RFE if it's a daily driver.

The 68RFE is also tunable should you go that route, the Aisin is not.

 

[John Jensen]

Not that the Aisin is bad IMHO, but you might experience better mannered trans shifting in the SO/68RFE if it's a daily driver.

The 68RFE is also tunable should you go that route, the Aisin is not.

Ha, ha. True Brutal, but tell the rest of the story. The 68RFE has to be tuned/modified to handle the tune's increased HP and torque. The Aisin is a much stronger tranny and can handle more power in its stock form, the HO is tuned with more HP and Torque than a tuned SO with its 68RFE. If the tuners ever break the Aisin code enabling it to be tuned, no telling what power they can achieve.

 

[Brutal_HO]

Ha, ha. True Brutal, but tell the rest of the story. The 68RFE has to be tuned/modified to handle the tune's increased HP and torque. The Aisin is a much stronger tranny and can handle more power in its stock form, the HO is tuned with more HP and Torque than a tuned SO with its 68RFE. If the tuners ever break the Aisin code enabling it to be tuned, no telling what power they can achieve.

I was trying to be brief.

 

[John Jensen]

I was trying to be brief.

And that you were

 

[Firebird]

My SO 3500 gets a few mpg better than my buddies HO 3500. Both are 2021 models

 

[hylasw]

My SO 3500 gets a few mpg better than my buddies HO 3500. Both are 2021 models

How does your SO 3500 tow ? Reason I am asking MPG on 3500 SO VS HO is I have a 28 ft fifth wheel camper weighs about 10,000 lbs, (if I sold it and bought another 5th wheel I won't buy anything bigger or much more weight as we go camping in lots of Mountain campgrounds and its hard to find large campsites) I will be towing that 10,000 lb. 5th wheel with my 3500 I am buying I am leaning toward the 3500 SO instead of HO because I have heard from some people it gets better MPG and I don't fell I need the extra power, I had a 2002 Ford 7.3 diesel which towed fine little slow up utah inclines but fine that had 250 HP and 505 Torque the 2022 Ram 3500 SO 6.7 has 370 HP and 850 Torque.

So anyhow how does your SO 3500 Tow and how heavy have you towed with it and does it go up high inclines fine ?

 

[tchur1]

Honestly the way you drive is going to have a much larger impact on MPGs then so vs Ho in my opinion. Based in the two threads you have posted it seems like the SO is more then adequate for your needs and you might see slightly improves efficiency.

 

[Firebird]

How does your SO 3500 tow ? Reason I am asking MPG on 3500 SO VS HO is I have a 28 ft fifth wheel camper weighs about 10,000 lbs, (if I sold it and bought another 5th wheel I won't buy anything bigger or much more weight as we go camping in lots of Mountain campgrounds and its hard to find large campsites) I will be towing that 10,000 lb. 5th wheel with my 3500 I am buying I am leaning toward the 3500 SO instead of HO because I have heard from some people it gets better MPG and I don't fell I need the extra power, I had a 2002 Ford 7.3 diesel which towed fine little slow up utah inclines but fine that had 250 HP and 505 Torque the 2022 Ram 3500 SO 6.7 has 370 HP and 850 Torque.

So anyhow how does your SO 3500 Tow and how heavy have you towed with it and does it go up high inclines fine ?

My TT loaded is right at 10,000 pounds, and my SO dually tows it effortlessly. My wife even commented on one of our recent trips, she said "I can't even tell you are pulling the camper"

 

[GPurcell01]

So this is perfect for me to give input. I have a 2021 CCSB 3500 HO. My father has a 2021 CCSB 2500 SO. Both trucks are Laramies with the sport package. Its apples to apples.

He consistently gets 1-2 mpg higher in all conditions. With that being said, I will gladly take that hit as he has already had issues with the 68rfe. My neighbor has a similar 2020 2500 who is also having the same transmission issues.

 

[The1adman]

SO you are saying you see that 1-3 MPG Better in the SO When towing ? Reason I am asking is I am going to be purchasing a new 2022 Ram 3500 I am only towing 10,000 lbs. 5th wheel with it 80-90% of the time I am using the truck I don't really think I need the HO and extra power but want the best MPG possible

Empty the SO was about 1-2 MPG better, towing the SO was 2-3 MPG better. I tow the same trailer on a 700 mile round trip 3-4 times a year. I keep track of every tank manually in a log book. I had no complaints about the SO towing 15K plus, the HO does it easier just burns more diesel.

 

[H3LZSN1P3R]

So anyhow how does your SO 3500 Tow and how heavy have you towed with it and does it go up high inclines fine ?

My 19 2500 SO has no issue with 20k even up 6-7% grades the 3500 SO will treat you well

 

[jebruns]

So this is perfect for me to give input. I have a 2021 CCSB 3500 HO. My father has a 2021 CCSB 2500 SO. Both trucks are Laramies with the sport package. Its apples to apples.

He consistently gets 1-2 mpg higher in all conditions. With that being said, I will gladly take that hit as he has already had issues with the 68rfe. My neighbor has a similar 2020 2500 who is also having the same transmission issues.

The 68rfe is a pretty good tranny in totally stock trucks, so I'm surprised to hear of 2 people you know having issues with them. Do they have tuners in them? Everyone I know that owns that tranny in stock trucks has had no issues with them, including mine.

 

[Firebird]

The 68rfe is a pretty good tranny in totally stock trucks, so I'm surprised to hear of 2 people you know having issues with them. Do they have tuners in them? Everyone I know that owns that tranny in stock trucks has had no issues with them, including mine.

I'm on my 4th 68RFE truck, and knock on wood, not a single issue with any of them