GBB
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I always lock out 5th and 6th gears while in town.
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6th gear lockout when towing or let it go?
- Thread starter brian.holtmann
- Start date
Whatever speed you run use the toggle to drop to whatever gear keeps you in the 1800 and up range. I don't have my Diesel anymore since I got rid of the big trailer. When you hit a hill and it down shifts I also use the toggle to maintain that gear until I start gaining speed again and need to upshift, that way if you ease out of the throttle a little it won't upshift just to need to downshift again. I did run hard when on the road and never a problem with either of my 6 speed automatics, although the Aisin seemed to work way better.
Just did an almost all highway, (not freeway), tow and watched to see what RPMs were running. Cruise control on 62mph. Tow haul on. 6th gear RPMs between 1400 and 1500 generally. 5th gear 1900 to 2000. So given the advice in this thread, 6th probably a bit too low and not ideal. 5th at 1900 - 2000 RPM maybe a bit higher than ideal but better than 1400 - 1500. Fuel use seems about the same even at the higher RPM.
H3LZSN1P3R
You're doing it wrong
The only time i lock out any gears is when im in hilly terrain or windy back roads
I don’t know how these newer trucks are but my 2012 with 3.73’s loves to be around 2k-2,200 rpm. I have pyrometer tapped into my exhaust manifold and manually shift by locking out gears 100% off my EGT numbers. I very rarely use 6th gear, and never while towing. It’s very cool to see the EGT react instantly when you downshift and bring RPMs back up to 2k. I also get better MPG up around 2k as opposed to lugging down around 1500. It is deleted with 35s for what it’s worth.
Have a 22 DRW on order HO/Aisin on order, will be interesting to see the differences.
Sent from my iPhone using Tapatalk
Have a 22 DRW on order HO/Aisin on order, will be interesting to see the differences.
Sent from my iPhone using Tapatalk
gimmie11s
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Youre gonna stress yourself out that way.
Also, how are you able to achieve better MPG at 2000 rpm vs 1500 rpm considering fuel is sprayed into the combustion chamber every engine revolution?
I’ve been driving it like that for 9 years. Pressing a + or - button while driving to keep my truck in its happy place isn’t exactly stressful.
Honestly I can’t answer that, I’m a jet mechanic, not an engineer. Although at this point in my career I question a lot of designs engineers come up with. I’m a numbers guy, I drive and react to the numbers my truck shows me. The MPGs are up and temps go down when my truck is hummin at 2k.
H3LZSN1P3R
You're doing it wrong
When newer engines are underload the injector pulse is longer to put more fuel in so rpm is less important compared to engine load also higher rpm means more boost which helps the engine run more efficiently…. That being said i have not noticed any milage change running 5th vs 6th
gimmie11s
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Gotcha.. so you are going off of the mpg meter on the display.
gimmie11s
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I understand all that, but that would suggest that the fuel demand difference "under load" at 1500 rpm vs 2000 rpm is so drastic that he achieves better mpg at 2000-2200rpm. Seems like a stretch, but hey.. as long as he's happy.
H3LZSN1P3R
You're doing it wrong
The biggest factor is the boost pressure at the higher rpm where it can reach the optimal fuel/air ratio but it wont be a drastic increase if even 1MPG id be surprised
Sure. I’m not going to run 2 tanks, one normally how I drive and 1 lugging the motor just to hand calculate it. It isn’t that deep. I just got back from a mostly residential drive on 35mph roads and here’s what I can tell you. At whatever speed I’m going, let’s say 4th gear has me at 1300-1400rpm, and downshifting to 3rd puts me at 1800 and my EGTs drop by 400 degrees instantly, and that little liar fuel meter jumps from 15ish to pegged at 20mpg, I’m going to listen to my truck and cruise in 3rd. Am I really getting 20? Probably not, but being deleted and running clean tunes I would bet I’m pretty close.
I wasn’t trying to create a debate. Simply giving my opinion on locking out gears as a positive when it comes to keeping your truck wherever it likes to be.
gimmie11s
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Fair enough, not debating.. it's a discussion forum. We discuss different ideas and opinions and how people get to and form said opinions.
You'd be surprised how many outlandish things people say on this forum.... almost as if no one else on this forum owns the same truck as them.
H3LZSN1P3R
You're doing it wrong
One note i might add is the fuel millage indicator seems to be pretty accurate on these trucks myself and others seem to be within .2 MPG after hand calculations
Yep, I agree. I love open discussion and learning new things from smarter people than myself. You won’t see me getting defensive or offended.
DRAGRAM
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First of all, if the truck is stock, I could care less about my EGT's. I never look at any of that crap. Also I find it interesting that so many seem to know more than RAM does. At MOST I run Tow/Haul. I almost NEVER lock out any gears. Again, if the truck is stock, what on earth is wrong with running the max EGT that the truck can achieve. Ever heard of a passive regen? I look at my DPF gauge and it always reads zero. Maybe it does not work? I also am not buying the better mileage at higher RPM. At least not beyond what the Tow Haul program achieves.
UglyViking
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As has been said by a few I only lockout 6th if I'm towing up steep grades or through hilly/windy conditions or if the truck seems to be hunting for a gear. I don't see the point in locking out an OD gear, especially while the truck is in tow/haul mode. These trucks have all sorts of protections in them by default, so unless you're running tuned/deleted I say let her eat.
As for the EGT temps being high, I can't see them getting high enough to be anywhere close to an issue on these newer trucks. These newer blocks are much stronger than the old blocks and can easily withstand much higher EGTs, not to mention the fact that you do want some EGT heat to keep the DPF "lit" as it will help with passive regen. You can lower it but the system is just gonna have to dump fuel and heat it after the fact so may as well get the energy from it by working the engine.
Again, if you're going through mountains, steep grades, very hilly terrain, or around town and your truck is at all hunting, then lock out 6th, hell I lockout 5th sometimes depending on where I'm at. I just don't personally see the need.
That said, I also notice a loss of MPG by 1-2 when I lockout 6th unnecessarily. It most likely has something to do with the fact I'm running 37s, but I'll take it.
As for the EGT temps being high, I can't see them getting high enough to be anywhere close to an issue on these newer trucks. These newer blocks are much stronger than the old blocks and can easily withstand much higher EGTs, not to mention the fact that you do want some EGT heat to keep the DPF "lit" as it will help with passive regen. You can lower it but the system is just gonna have to dump fuel and heat it after the fact so may as well get the energy from it by working the engine.
Again, if you're going through mountains, steep grades, very hilly terrain, or around town and your truck is at all hunting, then lock out 6th, hell I lockout 5th sometimes depending on where I'm at. I just don't personally see the need.
That said, I also notice a loss of MPG by 1-2 when I lockout 6th unnecessarily. It most likely has something to do with the fact I'm running 37s, but I'll take it.
Not sure what is meant by "many seem to know more than Ram does"? Ram did add the Lock-Out feature to the truck. I assume they expect drivers to use it when appropriate.
When frequent transmission shifting occurs
(such as when operating the vehicle under
heavy loading conditions, in hilly terrain,
traveling into strong head winds, or while towing
a heavy trailer), use the Electronic Range Select
(ERS) shift control refer to “Electronic Range
Select (ERS) Operation” in this section for
further information to select a lower gear range.
Under these conditions, using a lower gear
range will improve performance and extend
transmission life by reducing excessive shifting
and heat buildup.