HOV

Let's get to the heart of the issue here: why is it that a lot of built transmissions have the 1-2 flare and 2-3 shuttle issue? Does it affect mainly 2005+ trucks that have a TV motor? I just got my trans built and now I have problems I didn't have before, which makes me a little upset that I spent $4500 to have these problems. I'd figure the trans builders would know about these issues by now.

Is it that the increased line pressure from the modified valve bodies makes the ECU think that there's more throttle than what is actually being given, and it either holds the gear longer (in 1st to make it "flare") or kicks down for better acceleration (2-3 shuttle issue)?

For those with a DTT setup, what's the story on the adjustment of the voltage on the valve body? Also, does DTT offer a different/better gov press solenoid that may help deal with this problem?

Here's what I think are posible solutions, your opinions are valued:

- Move the upshift point from 2-3 to a higher speed. Keep the downshift point where it is. I believe one reason the shuttle shift happens is because the shift to 3 happens too early on hills with light throttle. Imagine this: you're climbing a hill and the speed passes 25 MPH, the trans shifts to 3rd. But then you back off on the throttle because you've reached your final speed and the engine starts to bogs a bit, so it shifts back down because it senses phantom throttle due to the higher line pressures. If 2 were held longer on the upshift, it would make more RPMs and not bog as soon, helping to eliminate one factor of the shift party. If the downshift point were held around 25, then you'd be safe to cruise level or at slight inclines in 3rd, and if the hill gets steep it will downshift to second and hold that longer.

- DTT shift enhancer. What's the story with that thing? What exactly does it do? As far as I'm concerned, it should be included with the trans for 2005-2007 models if it helps alleviate these problems.

jrussell

I think DTT would be the best people to answer those questions for you...especially if you're a new customer who's not really satisfied.

FWIW mine had the 2-3 gear hunting when stock, but not with the Goerend tranny. I also don't have the 1-2 flare because Dave installed a stiffer spring somewhere in the VB. The 1-2 flare can be due to certain programming. Are you running a programmer with less torque management than stock?

HOV

Nope, I run a chip only.

I spoke with my DTT installer and he recommended a DTT shift enhancer. He says the problems are due to the difference between line pressure in the valve body and what the TV motor is seeing for throttle position. In a nutshell, he said that the DTT shift enhancer tells the TV motor it's getting more throttle than it actually is, which helps balance that with the increased line pressure.

jrussell

I think the shift enhancer would solve your problem(s). Other people have reported that it solved their issues.

jgiachino

I have a DTT updated Trans and the shift enhancer....all installed at the same time.....solved the stock 1-2 issue, but still have the 2-3-2 issue and cant seem to resolve it (I think my installer gave up on me)....tried a diff spring in the vb (delay 3rd gear onset), lowered the voltage setting (i hated the way if felt)....no dice as of yet...but i haven't contacted DTT directly to resolve (will do after the holidays)....The setup is excellent other than this one issue, so hoping it can be resolved.

cameroneod

Shift enhancer isnt an option for those of us with "older" trucks. Pretty aggravating.

Jason A

With mine it holds on to 2nd a little longer than I'd like (2200rpms) and then launches you into 3rd. I also get a flare from 1-2 but not all the time.

Now I am in no way even a novice when it comes to this and cannot speak inteligently on these matter but I did talk to Dave (G) the other day about this and if I understood him correctly he mentioned that the DTT shift enhancer solved some / many of these issues for (more than a few) of his customers but also metioned the communication issue between the ECM VB pressure and the TV(?) motor as a very possible cause.

He told me I could spend the cash (on the shift enhancer) to see if it solved my issues or hang as he is currently working on a (TV motor?) solution.

Personnally this time of year there arent too many times I'll be hangin hard on the skinny peddle so I'm going to hold off.

Thanks again Dave for your time and explanations and not just selling me what I think I need!

Howling

I imagine this does the same as the DTT shift enhancer,but one thing that caught my eye was that it is plug and play.Is the DTT plug and play?

http://www.tsperformance.com/transmission.html

HOV

All the enhancer does is what the (free) cable adjustment does for your model year truck, except we have to pay $200 for it and splice into a factory wiring harness...

HOV

Keep us informed of how it goes. I should contact DTT directly also, before spending the cash on the enhancer.

omaharam

Here's my experiences. Notice it's an 04.5, so it still has the tv cable.

Never had any issues stock at all. Upgraded the VB and TC to Goerend units. Never had a single problem with this set up. So then I moved into quite a bit more power and needed to do more to the tranny. I had it built with extra and hd clutches as well as replacing the wave spring with a solid shim so third gear is an immediate engage. Well the problem was when it all went back together, with the new tranny internals, it shifted way too hard for my liking with the Goerend VB. It did NOT have any shifting issues at this point as far as flare or hunting - just way too harsh. Dave tried to give some suggestions as to what to try to fix it but with no luck. A DTT VB was installed at this point. It immediately had shifting issues and still was way too harsh. After many attempts to tweak it, Bill at DTT put together a "test" VB to try. From what I understand it's basically an RV set up with lower pressure so that it doesn't fight the TV pressure and do the 2-3-2 hunt. It seems to have worked. On the test drive everything seemed great. Once I got it home, it did have a couple little issues. It was shifting into 2nd too soon at light throttle and it kind of clunks from 2nd to 1st when slowing down. On my truck with the TV cable I was told to make an adjustment there. Well the weather has been nasty and I haven't done that yet. Then suddenly today it starts acting up really bad between 1 and 2 at light throttle. From 10-15mph it shifts about a dozen times at light throttle and it is also shifting back and forth if you slow down to about ten and let it coast with no throttle input. I'm going to have to climb under and adjust that TV and hopefully that will take care of it. If so, it seems it will be a good set up. No 2-3-2 hunt and still has nice firm shifts at anything 1/2 throttle and up.

Megaramasaur

I wa on the phone this weekend with Dave.... BTW... I think this guy walks on customer service water.... anyway, I have the DTT shift enhanser, and was having to run it on the 2nd setting (tow) to keep from having the 2-3 flare. While I had the VB dropped, he walked me through turning up the pressure. The flare is still there without the enhanser, but I can now drive on the daily setting with no flare. He did say he's working on modifing the electric TV motor to solve our problems. He said when he thinks he's got it figured out, he'll send me one out to test on my truck, but all in all, if dave programs the DTT to your VB pressure, the enhanser will solve your flaring issue.... I'm not sure about a 1-2 flare, all I've heard of is a 2-3 flare due to 2nd gear band not releasing when the 3rd drum engages.

HOV

^^

Sounds good, good luck with that. I'm wondering at this point why DTT hasn't come out with that kind of VB before. I'm a little miffed at this point that I need to spend more money to fix a problem I didn't have before.