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High Output (AISIN) vs Standard (68rfe)

MEGA HO 3500 said:
And to the guy asking if he needs to use the TH with a 4000# trailer... I wouldn't. I had a smaller trailer (loaded I guess it was in a 4500-5000# range). I made a trip with it last summer driving from AB to Vancouver Island and back. Thousands of miles through Rockies... When going downhill with TH (and EB obviously) activated, it felt like it was slamming breaks every once in a while. It was much too harsh. With TH off it was smooth and still I hardly ever had to touch breaks.
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I know with my 6 speed 6.4 tow haul locked out 6th gear. When I tried it for 10 seconds in my ho cummins it seemed to lock out 6th again. Is that the case with the diesels as well that 6th gear is locked out?
 
loveracing1988 said:
I know with my 6 speed 6.4 tow haul locked out 6th gear. When I tried it for 10 seconds in my ho cummins it seemed to lock out 6th again. Is that the case with the diesels as well that 6th gear is locked out?
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When my truck is in 6th and I press the TH, it stays in 6th until it downshifts, then it will not upshift back into 6th again. However I noticed my MPG in 6th or 5th were the same (steady towing on flat ground) so that made no difference to me in which gear it was.

Sent from my ONEPLUS A5010 using Tapatalk
 
Towing my 12k trailer behind my 2020 RAM 3500 HO/Aisin with 4.10 doesn't seem to lock out 6th gear in my truck in tow haul mode.
 
loveracing1988 said:
I know with my 6 speed 6.4 tow haul locked out 6th gear. When I tried it for 10 seconds in my ho cummins it seemed to lock out 6th again. Is that the case with the diesels as well that 6th gear is locked out?
Click to expand...

MEGA HO 3500 said:
When my truck is in 6th and I press the TH, it stays in 6th until it downshifts, then it will not upshift back into 6th again. However I noticed my MPG in 6th or 5th were the same (steady towing on flat ground) so that made no difference to me in which gear it was.

Sent from my ONEPLUS A5010 using Tapatalk
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RV_Goose said:
Towing my 12k trailer behind my 2020 RAM 3500 HO/Aisin with 4.10 doesn't seem to lock out 6th gear in my truck in tow haul mode.
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2020 3500 SRW HO/Aisin does not lock out 6th gear in TH unless I use the gear limiter.
 
The 68rfe will also not lock out 6th in T/H mode. I have to manually lock it out
 
RV_Goose said:
Towing my 12k trailer behind my 2020 RAM 3500 HO/Aisin with 4.10 doesn't seem to lock out 6th gear in my truck in tow haul mode.
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My 2020 HO/Aisin towing similar 12K had 6th gear also in Tow haul mode with 4.10 gears
 
Trans question: I noticed the available 2021 Ram 3500 DRW seem to all be spec'd out without the HO/Aisin. When I bought my 2020 and a lot of discounts were going on, every DRW was HO/Aisin..... Just wondering if anyone else has seen this. My 2020 is gone now. (Was able to get a great tradi in amount and went with the 7.3L gas Ford SD) Mixed emotions to say the least. The Cummins is a champ but the CP4 failure hit a friend of a friend and I got tired of a FCA solution. May go back to a 3500 later on but the ones popping up on Facebook and when I have looked are spec'd different for 2021.
 
You can get a DRW with the SO/68rfe. Tons of them out there and was an option when i ordered my '21.
 
Most ones left on lot are the so/rfe around here. HO/aisin, if they have them, are sticking close to MSRP.
 
Hey guys how’s it going. Just bought a 2021 3500 HO. I notice doing 70-75 I am basically at 2k 1900 RPM. In my 2018 SO I thought my RPM for that speed was just over 1500 maybe 1650. What are y’all seeing.


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Moose074 said:
Hey guys how’s it going. Just bought a 2021 3500 HO. I notice doing 70-75 I am basically at 2k 1900 RPM. In my 2018 SO I thought my RPM for that speed was just over 1500 maybe 1650. What are y’all seeing.


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Yup. 3.73 gearing. Your old truck probably had 3.42.

The peak efficiency is right at 1900-2000 so I wouldn't sweat it. Bump those lame Firestone factory tires up to a 35" and the RPM's will drop some, or you can run a little faster if desired.

What size tires? My gearing calculator seems a little off from what you're reporting. I poked around a bit and it seems you opted not get the 4.10 rear?
 
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Moose074 said:
Hey guys how’s it going. Just bought a 2021 3500 HO. I notice doing 70-75 I am basically at 2k 1900 RPM. In my 2018 SO I thought my RPM for that speed was just over 1500 maybe 1650. What are y’all seeing.


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You gotta have 4:10 gear then.
 
Oops read the 2k at 75. That’s where I am at at 70 ish with 4:10s maybe a smidge higher, my 2500 was 3:42 and lugged along at 15-1600.
 
So I apologize I did or thought I had filled out signature info even thought I imported pic of the truck. It’s a 2021 Laramie 3500 dually HO with 3:73 my last truck was 2018 Tradesman 3500 DWD SO with 3:73 gearing. I just verified per vin that I have the 3:73. I believe last truck had 11.5 rear this one the 12 stock 17” tires both


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Seems like as long as you are in the 2000 RPM range or below is the sweet spot for mileage.
 
Moose074 said:
So I apologize I did or thought I had filled out signature info even thought I imported pic of the truck. It’s a 2021 Laramie 3500 dually HO with 3:73 my last truck was 2018 Tradesman 3500 DWD SO with 3:73 gearing. I just verified per vin that I have the 3:73. I believe last truck had 11.5 rear this one the 12 stock 17” tires both


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Mind sharing the actual tire size. Not sure on the dually's... P235/75R17?

ETA: Corrected for 235/80R17.
1620937159093.png
 

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