2010 545rfe explanations

[gottaramit2020]

I have just picked up HPT to play around with my 2010 1500 5.7L.
As far as HPT terminology it is a foreign language. I have a fairly extensive knowledge of automatic transmissions, but am lost in terms of which options do what. For starters, the Pressure options are not just specified values. They are a duty cycle graph. There are other threads on this but they specify max PSI values and such that I do not see anywhere. I'm wondering if that's a model/year difference issue . Also there are thread explanations for desired acceleration offset but nothing on ramp rate of acceleration. Any extra explanation on these parameters would be greatly appreciated. I have attached the stock tune so the transmission parameters are reviewable.

[gottaramit2020]

So I figured out how to actually put HPT into advanced view. Found the Line pressure options I was looking for earlier. However, any info on Ramp Rate would still be very appreciated. Thanks

[Jim P]

Ramp rate is just how aggressively it applies the acceleration slew tables.

[gottaramit2020]

Ramp rate is just how aggressively it applies the acceleration slew tables.

OK thank you. Any idea what units it is measured in? So the Desired acceleration options are shift speed, and Ramp rate is the rate at which the shift speed is performed? Im assuming ramp rate is a ratio then, In example 1-2 shift speed is 7,000rpm/s and ramp rate is x1.3 that. Or am I missing the whole concept?

[Jim P]

Ramp rate of acceleration is a unitless number, it?s a gain, the higher the number the more aggressive it is at applying the desired acceleration slew tables. You have an A and a B, one is for off going clutches and the other is for oncoming clutches. Shift duty cycle will make it shift faster. Datalogs of the transmission helps a lot to see what?s going on.

[gottaramit2020]

Ramp rate of acceleration is a unitless number, it?s a gain, the higher the number the more aggressive it is at applying the desired acceleration slew tables. You have an A and a B, one is for off going clutches and the other is for oncoming clutches. Shift duty cycle will make it shift faster. Datalogs of the transmission helps a lot to see what?s going on.

Fair enough, now that I'm not completely in the dark I do feel comfortable logging and tweaking this parameter. Thank you for your insight.

[Allen Vos]

Ramp rate of acceleration is a unitless number, it?s a gain, the higher the number the more aggressive it is at applying the desired acceleration slew tables. You have an A and a B, one is for off going clutches and the other is for oncoming clutches. Shift duty cycle will make it shift faster. Datalogs of the transmission helps a lot to see what?s going on.

So touching on the shift duty cycle charts, it appears the numbers go higher as the throttle is increased.

So is it safe to assume that 'increasing" the shift duty cycle numbers will make for a faster/shorter shift?

Sorry, I am a GM guy and everyone does things a bit differently lol

[Jim P 2.0]

Don’t know where you are getting throttle position on the shift duty cycle tables, it’s duty cycle % based on torque

[Allen Vos]

Don?t know where you are getting throttle position on the shift duty cycle tables, it?s duty cycle % based on torque

Mine is in a 2010 dodge ram 1500.

Under Transmission/shift pressures/upshift I have 6 duty cycle options

Lets pick the 1-2 shift tab - ECM-46102

It clearly states the duty cycle vs throttle position.

Not sure what else to tell you, unless its the newer stuff that is torque based?

I'm typically playing around with the GM LS motors and they don't start basing torque based tuning until 2014

All I am wondering is if higher duty cycle numbers do dictate a faster shift?

[LilSick]

Lets pick the 1-2 shift tab - ECM-46102

I'm typically playing around with the GM LS motors and they don't start basing torque based tuning until 2014

All I am wondering is if higher duty cycle numbers do dictate a faster shift?

yeah pick that one. look at the X axis. its obviously mislabed...

do chevy throttle bodies open 195% to try to make up for the fact that they can not withstand nitro like a mopar can lol. no. a scale of 0-200 sounds a lot more like NV ratio than throttle opening percent to me

i am pretty sure it is the other way around in this case and a lower expected dc value would indicate an expectedly quicker shift

[Jim P 2.0]

Lower shift duty cycle too much it will struggle to shift, increasing will have slightly quicker shifts and hit shifts harder. Shift duty cycle is only a sliver of the pie to getting shifts to happen quicker though.

[Jim P 2.0]

Mine is in a 2010 dodge ram 1500.

Under Transmission/shift pressures/upshift I have 6 duty cycle options

Lets pick the 1-2 shift tab - ECM-46102

It clearly states the duty cycle vs throttle position.

Not sure what else to tell you, unless its the newer stuff that is torque based?

I'm typically playing around with the GM LS motors and they don't start basing torque based tuning until 2014

All I am wondering is if higher duty cycle numbers do dictate a faster shift?

Mislabeled axis, it is duty cycle against torque. Or you can just take it as throttle position because HP Tuners has never ever mislabeled something or mapped something out wrong, ever.

[Allen Vos]

yeah pick that one. look at the X axis. its obviously mislabed...

do chevy throttle bodies open 195% to try to make up for the fact that they can not withstand nitro like a mopar can lol. no. a scale of 0-200 sounds a lot more like NV ratio than throttle opening percent to me

i am pretty sure it is the other way around in this case and a lower expected dc value would indicate an expectedly quicker shift

Lol I don't need Nitro on my chevy.

I wasn't sure about the 195% throttle, which is why I am asking. I can tell you first hand GM has some pretty dumb ways of doing things with the tuning so I'm sure there are some with dodge as well. lol

With regards to the duty cycle, doesn't a lower duty cycle on the shift solenoid means that it does not flow as much fluid, therefore not shifting as quick?

It makes sense that a higher duty cycle would pass fluid through the solenoid quicker, thus hitting the clutch drum with fluid quicker for a quicker shift?

On the GM 6L80's I build at work, when we tune we shorten the shift timing by 30% for quicker shifts, but also increase line pressure by 30% overall, also eliminate and slip in the convertor and only lock it up in 5th and 6th gear.

They work really well this way so I was just going to do much of the same to this dodge and see how it works

Sorry for my ignorance, but what does NV ratio mean?

[Allen Vos]

Lower shift duty cycle too much it will struggle to shift, increasing will have slightly quicker shifts and hit shifts harder. Shift duty cycle is only a sliver of the pie to getting shifts to happen quicker though.

Ok, that's what I was thinking. I was going to give it about 30% more line pressure overall as well. We are adding 4.56 gears with a 37" tire and a TSP stage 2 cam with approx a 2800 stall, so I was going to rework the shift points and I was thinking of not having any lock up until 5th and 6th gear for cruising only. Also turning the convertor slip functions off or to zero.

[Jim P 2.0]

If you are running a stock valve body do not use anymore than 170 psi line pressure. Not engaging lockup until 5th or 6th just causes excess heat, slip and less power to the ground. Most likely you do not have the parameters mapped to completely zero out all slip nor is it actually a good idea as you could end up with clutch engagement overlaps causing binding. There is far more going on inside the transmission control than what meets the eye when looking at HP Tuners.

[Allen Vos]

If you are running a stock valve body do not use anymore than 170 psi line pressure. Not engaging lockup until 5th or 6th just causes excess heat, slip and less power to the ground. Most likely you do not have the parameters mapped to completely zero out all slip nor is it actually a good idea as you could end up with clutch engagement overlaps causing binding. There is far more going on inside the transmission control than what meets the eye when looking at HP Tuners.

So the stock line pressure on this 545RFE is 120 PSI. A 30% increase puts it at aprox 156 psi which is well within your parameters of 170 PSI.

I rebuild transmissions for a living, however there is some confusion from your response.

I tune the 6L80, 8L90 and 10L90 all on the GM side of things, as well as the Ford 6R80 and the 10R80.

On all these transmissions I generally increase overall line pressure 25-30% and shorten the shift timing by 25-30%.


Any Converter slip is permanently eliminated by setting to zero, as well as lockup only being applied in the top 2-3 gears at cruising speed.

I have never had any issues with any excess heat or convertor inefficiency not putting power to the ground.

I also don't like locking them up under full power, especially with increased power due to engine mods as this is hard on the stock single disc convertors.

If we have a customer with a turbo application or high powered engine we always recommend a multi disc convertor if they want to lock that convertor under full power.

Generally all these changes make for a big improvement on shifting and how the transmission works over stock.


Eliminating the slip also makes the convertor last a lot longer. A lot of modern day transmission issues are caused from the clutch fibers from a slipping converter plugging up the filter and causing line pressure loss, then transmission failure.

I see this in a pile of GM's, Fords and even the dodge 62TE caravan transmission.


So my question to you is why would the dodge transmission exhibit signs of clutch overlap causing binding as you say when you don't allow slip on the convertor?

Do the dodges struggle with applying and releasing the clutches that they need convertor slip to mask up a bad shift so to speak?

As far as setting the convertor on the dodge to zero slip, isn't that just done under torque convertor/general/TCC shift slip, ECM 10200?

Not trying to come across as a know it all, but just trying to understand why a person wouldn't eliminate slip on the dodges when it works with every other transmission I have tuned?

[Jim P 2.0]

[QUOTE=Allen Vos;821103]
As far as setting the convertor on the dodge to zero slip, isn't that just done under torque convertor/general/TCC shift slip, ECM 10200?
/QUOTE]

this value is added to turbine rpm and compared against filtered engine rpm as part of shift delay for downshifts, so it is an offset value

[Jim P 2.0]

The 2010 545RFE tune file that is attached at the top of this thread has virtually no actual slip parameters mapped out, just as an FYI.

[Allen Vos]

The 2010 545RFE tune file that is attached at the top of this thread has virtually no actual slip parameters mapped out, just as an FYI.

ok, I will take a look at it when I get some free time.

Stay tuned.... More questions to come lol

[Jim P 2.0]

Not sure which calibration you are looking at, if it’s a 2010 RFE, probably not really any different from the one at the top of this thread and it doesn’t have the slip time tables mapped out for the clutches or any of the negative/positive slip control parameters for the torque converter mapped out. There is probably like less than 1/5th of the transmission parameters mapped.