SCT Tuner

[DIESEL FOOL]

Well, it was Friday, my exhaust was on, I had beer, and I could not take it anymore. Stroken's truck was done with his Spartan tunes and it is rippin. He absolutely needs a one piece driveshaft like the one I put on as his steady bearing is just pounding we he drops the hammer. I am still waiting for my Spartan unit to come in, so I installed this thing to see what it was like for SAG. Well after I loaded the "extreme tune" I fired it up and everthing seemed fine, but when I test drove it, the transmission almost fell out I am sure. It could not decide what gear to be in and was jumping back and forth. The boost gauge was pegged after partial throttle and it was defueling. I think a stock Neon would kick my ass. Once it did get into high gear and you mashed it, the thing did haul ass, but the shifting was scary to say the least.
I tried the 120 and 60 horse tunes and they all shifted bad. It seemed like the truck was labouring and slipping. No lights however. I put the truck back to stock and reloaded the tune. The "extreme" was still crap and caused two codes 766 and 2307 this time which are both related to no third gear I believe. I then tried the 120 tune again with much better results, but it is still making high boost early then defueling. I emailed SCT to see what gives, and they want me to call them back from inside the truck and see if they can figure it out. I don't want any part of the thing and hope my Spartan unit shows up soon before I have a transmission bill. The mileage with the 120 says 13 mpg in the city with normal driving which is pretty good with 37" tires. I have not taken it on the highway.
Seeing as I had a 6.0 before which would build power forever with a big tune, is it normal for the 6.4 have to defuel so much to avoid overboost?, or is this just part of this crappy SCT tuner? Stroken's truck seemed to hold at 30-35 psi boost with the 250 in.

[bcjag72]

I didn't think the extreme 1.2.2 was that bad. The shifting was alittle rough and between 40-55 the rpms go up and down. Thought it had good power, but I like the Spartan better. I am using the 210 right now cause I think the 250 is too much power and the shifting from 1-2 is rough. Tons of power, scarr power!

[DIESEL FOOL]

No, I think there is something wrong with this particular download. After I downloaded it a second time, it was better in the 120 down tunes. They want to try to fix it, but I am getting rid of it a soon as my Spartan shows up.

[BigIslandBoy]

I didn't think the extreme 1.2.2 was that bad. The shifting was alittle rough and between 40-55 the rpms go up and down. Thought it had good power, but I like the Spartan better. I am using the 210 right now cause I think the 250 is too much power and the shifting from 1-2 is rough. Tons of power, scarr power!


The shifting needs to firm on the 250, it is better for your tranny believe or not, because it protects it from slipping.

[DIESEL FOOL]

Firm shifting is good, but ripping the transmission apart is not. The truck will literally snap your head forwards and backwards while trying to shift into third.The SCT in my opinion is junk. I would not recommend it to anyone. I had a Predator in my 6.0 and it was trouble free. I will be all over my UPS guy when he shows up with the Spartan.

[mick1955]

DIESEL FOOL - What kind of egt's were you seeing when it defueled?

[pipeliner]

I'd say the problem is that these tunes are for your buddies buddies truck, strategy code, vin number and such. If they didn't need all of that info they wouldn't have asked for it

[DIESEL FOOL]

Mick1955 - The temperatures do not even get the chance to get hot. When I hammer down, the engine pulls pretty hard until the boost hits 40+ which is extremely fast and then it just stops pulling. The truck will shift next gear, dropping the boost again, then it pulls to 40+ again. Once it is in top gear, it pulls hard, easily burying the needle.
I would say that the truck, at moderate throttle, will make full boost in 8-9 seconds. At full throttle it is more like 4-5 seconds. Then it just plain runs out of steam. At 40+ boost, the engine will never go over 3200 rpm. It don't know what is wrong with it, but my Spartan tune is shipping today, so i am going to hang in there and take it easy on the young girl.

[DIESEL FOOL]

The exact same problem I am having is described by texguy75 under troubleshooting and tech support. The thread was called "Tranny Problem" dated 09/09/2008. There never was a solution posted, but now I am worried.

[mick1955]

DIESEL FOOL - I think you have probably already figured out your what the problem is! I really think it's the tune on the tuner. One thing for sure, when you get the DashDaq and if (hopefully) the problem is gone, you will know for sure. Could be wrong, due to the fact that I have never ran the SCT, and I am no computer programmer. Think God! I think if I was, I would not have any hair left. Sometimes trying to help some of the guys on this form is hard enough. I am not complaining tho, cause it is a lot of fun trying to explain to someone how to do something on a computer/DashDaq when what you are trying to get them to do is getting lost in the translation. But, the best part of it is the people you meet, even if it's only over the phone! Welcome to the Spartan Family!

[DIESEL FOOL]

mick1955-

Thanks for the help and the welcome. I sure hope the DD fixes my problem. I have this SCT POS working not too bad now with the 120 tune in it. Good enough until the DD comes in anyways. We have a dyno down the street from our shop and my business partner Stroken, is trying to talk me into doing a couple of runs with the SCT before I get rid of it. I don't think it would be worth a transmission though.