Transmission downshift adjustment/info/understanding

Predator support for Dodge gas vehicles

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NWRQC
Posts: 7
Joined: Tue Nov 29, 2011 5:37 pm

Transmission downshift adjustment/info/understanding

Post by NWRQC »

U7137 2005 ram 1500 Hemi.

I am in the process of trying to figure out the best transmission shift points for my driving style and liking. I understand the upshift settings and have adusted them a little. The problem that I am having is understanding the downshift portion. I'm sure it's probably as easy to understand as the upshift, but I cant quite grasp it, so I am hoping that someone here can give me a hand. I found some settings online to use as a starting point and have made some adjustments to suite me.
(percentages are not the same as what the predator allows me to adjust on my truck, but close)
Upshift:
1-2 20% 1700rpm
1-2 30% 2600rpm
1-2 60% 5051rpm
1-2 80% 5351rpm
2-3 15% 1526rpm
2-3 25% 1803rpm
above raised slightly from stock
2-3 60%, 80% stock.
I am still adjusting slightly to suit my liking.... I;m good there.
Here is my confusion...Downshifts. The first RPM numbers are what the DSP displays when I click on the shift setting (i.e 2-1 @ 5%) and the second set of RPM numbers are what I found online that someone else uses (a starting point for which I was going to use).
Downshifts:
2-1 5% unsure ....... 1325rpm
2-1 80% 1503rpm .....4100rpm
3-2 45% 1603rpm ......4750rpm
3-2 55% 3000rpm ......4750rpm
3-2 75% 5150rpm .......5250rpm

So if I want the transmission to shift down a little sooner, do I adjust the first set of numbers up or down? The "online" numbers seem out of proportion compared to the stock numbers.
Right now my truck feels like it should drop down to second but holds third gear so it feels sluggish.
Example. I was driving down the road and slowed down to make a turn on a cross street. As I turn and accelerate (say 30% throttle) the truck stays in 3rd gear instead of dropping down to 2nd. The RPM are low(say 1400rpm) so the truck feels sluggish until they get up around 1800rpm. Would I have to adjust the downshift RPM up or down.
Maybe I am searching the wrong terms, but I am finding very little on this topic (on this site and others) so any help is appreciated.
Thanks
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white_lightning
Posts: 720
Joined: Tue Jan 13, 2009 3:31 pm

RE: Transmission downshift adjustment/info/understanding

Post by white_lightning »

custom trans tune is better than modified stock tune, IMO.

I am a CMR tuner have trans tuned several Rams and a few Jeep with good results. I can send you the same shifts that are in my 2005 Ram for a fee, and you don't have to puzzle over what to set how.

my upshifts are a bit higher than stock and downshifts are more sensitive. shifts are also faster and firmer than stock.

PM me if you are interested.
Diablo Dodge CMR Tuner

Cell Phone#: (520) 508-5320

[email protected]

My Ride:
2005 Ram QC 1500, APS converter, 210/214 112 LSA cam, LT headers, True Duals, 4.56 gears, 180* T-Stat and some other mods. Tuned by Me.
NWRQC
Posts: 7
Joined: Tue Nov 29, 2011 5:37 pm

Re: RE: Transmission downshift adjustment/info/understanding

Post by NWRQC »

white_lightning wrote:custom trans tune is better than modified stock tune, IMO.

I am a CMR tuner have trans tuned several Rams and a few Jeep with good results. I can send you the same shifts that are in my 2005 Ram for a fee, and you don't have to puzzle over what to set how.

my upshifts are a bit higher than stock and downshifts are more sensitive. shifts are also faster and firmer than stock.

PM me if you are interested.
I am interested in a CMR tune for a few reasons, and will probably PM you to inquire further. At this point though I am trying to understand the above mentioned downshifts (percentages vs RPM). Before I jump into stuff I like to understand how and why it works incase I run into issues down the road I have an understanding of how it works and what possibly could have gone wrong. Can you shed a little light on that?
I know that custom tunes are well worth the money spent, no question there. Having done a bit of custom engine tuning on a previous vehicle, then having the same vehicle tuned by a professional tuner the performance and reliability is far superior.
Thanks.
LeHemi
Posts: 25
Joined: Wed May 05, 2010 2:52 pm

RE: Re: RE: Transmission downshift adjustment/info/understan

Post by LeHemi »

Not to change the subject, but I do not have the downshift adjustments for my 2010 Ram Hemi, am I missing something? I would also like to understand how this works.
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white_lightning
Posts: 720
Joined: Tue Jan 13, 2009 3:31 pm

Re: RE: Transmission downshift adjustment/info/understanding

Post by white_lightning »

NWRQC wrote:
white_lightning wrote:custom trans tune is better than modified stock tune, IMO.

I am a CMR tuner have trans tuned several Rams and a few Jeep with good results. I can send you the same shifts that are in my 2005 Ram for a fee, and you don't have to puzzle over what to set how.

my upshifts are a bit higher than stock and downshifts are more sensitive. shifts are also faster and firmer than stock.

PM me if you are interested.
Before I jump into stuff I like to understand how and why it works incase I run into issues down the road I have an understanding of how it works and what possibly could have gone wrong. Can you shed a little light on that?

Thanks.
raising upshift makes you hold a gear longer before shift. I set my 1-2 @ 20% for 1,800 and 2-3 @ 15% for 1,800.

what the tuner doesn't do that makes a big difference is:
raise the 0% shift points, which I have at 1,800 also, which means my truck holds the gear until 1,800 even coasting at 0% throttle.

raised downshifts make the down shifts more sensitive.
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white_lightning
Posts: 720
Joined: Tue Jan 13, 2009 3:31 pm

Re: RE: Re: RE: Transmission downshift adjustment/info/under

Post by white_lightning »

LeHemi wrote:Not to change the subject, but I do not have the downshift adjustments for my 2010 Ram Hemi, am I missing something? I would also like to understand how this works.
you should have downshifts. they should be in "modify tune".

what Crom do you have? if you don't have 9r13, try it.
NWRQC
Posts: 7
Joined: Tue Nov 29, 2011 5:37 pm

Re: RE: Transmission downshift adjustment/info/understanding

Post by NWRQC »

white_lightning wrote:
NWRQC wrote:
white_lightning wrote:custom trans tune is better than modified stock tune, IMO.

I am a CMR tuner have trans tuned several Rams and a few Jeep with good results. I can send you the same shifts that are in my 2005 Ram for a fee, and you don't have to puzzle over what to set how.

my upshifts are a bit higher than stock and downshifts are more sensitive. shifts are also faster and firmer than stock.

PM me if you are interested.
Before I jump into stuff I like to understand how and why it works incase I run into issues down the road I have an understanding of how it works and what possibly could have gone wrong. Can you shed a little light on that?

Thanks.
raising upshift makes you hold a gear longer before shift. I set my 1-2 @ 20% for 1,800 and 2-3 @ 15% for 1,800.

what the tuner doesn't do that makes a big difference is:
raise the 0% shift points, which I have at 1,800 also, which means my truck holds the gear until 1,800 even coasting at 0% throttle.

raised downshifts make the down shifts more sensitive.
That makes sense (making downshifts more sensitive) but the part that is throwing me off is that raising the RPM (say from 2100 to 3700 @25%) makes the shifts more sensitive. I would think that it would be the opposite.
Holding the gear longer at 0% does sound like something that I would like, which leads me into my next question. With increased downshifts (say in city driving) do you think that it will create more heat in the transmission? or since the upshifts are held longer it evens out? Would a larger tranny cooler be benifitial?
I appreciate you taking the time to respond, and anyone else who contributes. If not just for me to gain a better understanding, maybe the next guy in my situation can come across this thread and learn something.
Thanks.
LeHemi
Posts: 25
Joined: Wed May 05, 2010 2:52 pm

RE: Re: RE: Transmission downshift adjustment/info/understan

Post by LeHemi »

I am running 9r13
, the only trans adjustments I have are part throttle upshift and rpm shift points which only list 1-2 upshift and 2-3 upshift
NWRQC
Posts: 7
Joined: Tue Nov 29, 2011 5:37 pm

Re: RE: Re: RE: Transmission downshift adjustment/info/under

Post by NWRQC »

LeHemi wrote:Not to change the subject, but I do not have the downshift adjustments for my 2010 Ram Hemi, am I missing something? I would also like to understand how this works.
This is probably a shot in the dark because I am still learning the in's and out's. On mine I don't have any upshift/downshift adjustment options when modfying the tune unless I turn the ignition on prior to plugging the tuner in. The DS wont recognize the transmission unless I do it that way (I ran across that technique digging through posts). I verify that by checking the calid and making sure it shows the ECM and TCM serial numbers.
LeHemi
Posts: 25
Joined: Wed May 05, 2010 2:52 pm

RE: Re: RE: Re: RE: Transmission downshift adjustment/info/u

Post by LeHemi »

I will give that a try tomorrow, thanks.
LeHemi
Posts: 25
Joined: Wed May 05, 2010 2:52 pm

RE: Re: RE: Re: RE: Transmission downshift adjustment/info/u

Post by LeHemi »

Thanks for the tip, but I tried that this morning and the only number it would show was PCM number. So still no downshift adjustment.
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white_lightning
Posts: 720
Joined: Tue Jan 13, 2009 3:31 pm

Re: RE: Transmission downshift adjustment/info/understanding

Post by white_lightning »

NWRQC wrote: With increased downshifts (say in city driving) do you think that it will create more heat in the transmission? or since the upshifts are held longer it evens out? Would a larger tranny cooler be benifitial?
increased downshifts should make your tranny run cooler in city. less converter slip by being in a lower gear at a higher rpm.

upside of cooler tranny is longer component life, downside is electronic trannies shift firmer when they are warm, about 180- 190*F.
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