6-speed tuned trucks Cruise control

B585Ford · Aug 6, 2012

Johnny77Mutt said:
Yeah how does it know what gear is selected? I only had a cruise problem once, it was some wack h&s update where everything else was screwy too. I couldnt live without cruise with the amount of miles I put on, I even added it to my 7.3.

So other than keeping up with the updates frlom H&S, you haven't had to do anything to to get it to work?

Johnny77Mutt · Aug 6, 2012

My brake pressure sensor went bad one time, but that's totally unrelated. I was kind of worried when I got the KEM tunes, first thing I tried was the cruise haha.

CAT35niner · Aug 9, 2012

Mine works now thanks to Josh at RCD. His tune runs so strong in it now. Its definitely my dd tune now.

Breaking Habits · Aug 9, 2012

Blcksmk08 said:
Mine works now thanks to Josh at RCD. His tune runs so strong in it now. Its definitely my dd tune now.

Glad to hear that new tune runs well.. told you it would be worth the wait

CAT35niner · Aug 9, 2012

Jared @ River City Diesel said:
Glad to hear that new tune runs well.. told you it would be worth the wait

Yea buddy. Im gonna give u a call later.

Breaking Habits · Aug 9, 2012

Blcksmk08 said:
Yea buddy. Im gonna give u a call later.

10/4. Ill be here haha

H&S Bentley · Aug 9, 2012

Here is what I have learned over the last few years of toying with the 6.4L.

1. Cruise can be disabled by any fueling related DTC. If you are running a big tune, you are likely on the verge of draining the rail. This will cause a P0087 code. Now, that code takes 2 consecutive key cycles to illuminate the CEL on the dash. So you may not see a code, but if you go to pass someone and lay into it a little bit, internally the ECM is throwing a fault for rail pressure being out of range low. Because this is a fuel related code, ECM cuts cruise until the next key cycle, at which time the diagnostics for P0087 runs again and passes. We have toyed with modifying the rail pressure hysteresis levels so that the code doesn't get thrown internally, but it seems there are a few more pieces to the puzzle. We need to spend more time on it in the future to learn all the ins and outs.

2. Cruise has literally hundreds of thresholds and control parameters that make it function. As an outsider it may look really simple to make a vehicle hold XX speed, but to make a computer smart enough to logically do this, and safely, is a BIG amount of code.
When an aftermarket tuning company tunes a calibration for a truck, they rarely tune EVERY calibration ford releases. To date there are about 200 different flashes on the market for the 6.4L Powerstroke ECM. To maintain tuning on these calibrations would take a team of engineers working solely on tuning and maintenance (nearly impossible). A waste of time if you ask me. Instead, a generic base file usually used to tune trucks, and modified to work with multiple vehicle configurations (gear ratios, fuel tanks, tire sizes, GVWR, up-fitter packates, etc.)
Many of the cruise control conditions that must be met are speed/gear position related. By using a base file for trucks, some of the base values may be incorrect for your vehicle, kicking one or multiple cruise control parameters out of range, and killing your cruise. The ECM calculates a gear position based off of speed/rpm values and a known set a gear ratios programmed in the calibration file, and thus can calculate when it is in or out of range. (yes it uses the clutch switch as part of the input to these calculations, so shifting "dry" can help cruise remain operational)
We, at H&S, have been trying to get our hands on an manual trans 6.4 for some time now, but have yet to come across one local. We almost bought one a few months back, just to universalize the cruise control functions to work across all variables, but then got busy with some other projects. If any of you are close to Utah, we would gladly pay your fuel costs to travel out here for a day. It should only take a day or so to throw a couple of test files to the truck to diagnose what parameters are being thrown out of range, and provide a fix for it. Let me know if any of you are interested, and we will schedule something! I know it must be frustrating when the cruise does not work, and we would love to provide a fix!

Hope that clears things up a bit!

Breaking Habits · Aug 9, 2012

It works out great when one of your employees has a manual 6.4

H&S Bentley · Aug 9, 2012

Jared @ River City Diesel said:
It works out great when one of your employees has a manual 6.4

Cheater! Yeah, one day when I get a second we will find one and get it fixed. It has bothered me since we first released 6.4L tunes. Or you can just send me your file and I'll learn what you changed! :thumbsup:

Na, I gotta learn on my own.... it is on my ever-growing "to do" list.

B585Ford · Aug 9, 2012

H&S Bentley said:
Here is what I have learned over the last few years of toying with the 6.4L.

1. Cruise can be disabled by any fueling related DTC. If you are running a big tune, you are likely on the verge of draining the rail. This will cause a P0087 code. Now, that code takes 2 consecutive key cycles to illuminate the CEL on the dash. So you may not see a code, but if you go to pass someone and lay into it a little bit, internally the ECM is throwing a fault for rail pressure being out of range low. Because this is a fuel related code, ECM cuts cruise until the next key cycle, at which time the diagnostics for P0087 runs again and passes. We have toyed with modifying the rail pressure hysteresis levels so that the code doesn't get thrown internally, but it seems there are a few more pieces to the puzzle. We need to spend more time on it in the future to learn all the ins and outs.

2. Cruise has literally hundreds of thresholds and control parameters that make it function. As an outsider it may look really simple to make a vehicle hold XX speed, but to make a computer smart enough to logically do this, and safely, is a BIG amount of code.
When an aftermarket tuning company tunes a calibration for a truck, they rarely tune EVERY calibration ford releases. To date there are about 200 different flashes on the market for the 6.4L Powerstroke ECM. To maintain tuning on these calibrations would take a team of engineers working solely on tuning and maintenance (nearly impossible). A waste of time if you ask me. Instead, a generic base file usually used to tune trucks, and modified to work with multiple vehicle configurations (gear ratios, fuel tanks, tire sizes, GVWR, up-fitter packates, etc.)
Many of the cruise control conditions that must be met are speed/gear position related. By using a base file for trucks, some of the base values may be incorrect for your vehicle, kicking one or multiple cruise control parameters out of range, and killing your cruise. The ECM calculates a gear position based off of speed/rpm values and a known set a gear ratios programmed in the calibration file, and thus can calculate when it is in or out of range. (yes it uses the clutch switch as part of the input to these calculations, so shifting "dry" can help cruise remain operational)
We, at H&S, have been trying to get our hands on an manual trans 6.4 for some time now, but have yet to come across one local. We almost bought one a few months back, just to universalize the cruise control functions to work across all variables, but then got busy with some other projects. If any of you are close to Utah, we would gladly pay your fuel costs to travel out here for a day. It should only take a day or so to throw a couple of test files to the truck to diagnose what parameters are being thrown out of range, and provide a fix for it. Let me know if any of you are interested, and we will schedule something! I know it must be frustrating when the cruise does not work, and we would love to provide a fix!

Hope that clears things up a bit!

Very cool of you to take the time to post this. Thanks for the info. I would love to volunteer but Utah is about 30 hours away.

superdutyfarmer · Aug 9, 2012

I agree, utah is a ways away from PA. Jared, if you wouldn't mind, shoot me a pm with a price for one of your tunes that would be good for everyday driving. I personally like Innovatives Street tune or Extreme Street if that helps to compare

CAT35niner · Aug 9, 2012

superdutyfarmer said:
I agree, utah is a ways away from PA. Jared, if you wouldn't mind, shoot me a pm with a price for one of your tunes that would be good for everyday driving. I personally like Innovatives Street tune or Extreme Street if that helps to compare

I personally recommend the 585 tune. Me likey alot lol.

superdutyfarmer · Aug 9, 2012

My problem is Idk what the pulsewidth is on that. I still only have the stock hpfp with 30% nozzles. If I hit the lottery and could get the dual pumps from RCD I'd have it made haha.

Breaking Habits · Aug 10, 2012

superdutyfarmer said:
My problem is Idk what the pulsewidth is on that. I still only have the stock hpfp with 30% nozzles. If I hit the lottery and could get the dual pumps from RCD I'd have it made haha.

30% nozzles and stock pump? Wowza

Sent from somewhere away from my desk using magic.

superdutyfarmer · Aug 11, 2012

So I guess rcd isn't interested in helping me out with a tune?

Johnny77Mutt · Aug 12, 2012

I'm sure they will help you out.

Breaking Habits · Aug 12, 2012

Its going to take a lot of fine tuning for stock pump and 30%s

Sent from somewhere away from my desk using magic.

CAT35niner · Aug 12, 2012

I can finally post this. Its nice to be able to use it again.

Johnny77Mutt · Aug 12, 2012

Its also nice having a full fuel tank!

CAT35niner · Aug 12, 2012

Always lol. I never go below half. Gets to much bellow that. With the drive out to PA and back i averaged 19.1mpg hand calculated. Pretty good for a 800hp truck. Im definitely lovin cruise with this setup.