DieselGuyMike

Hi everybody, I have been lurking around here for over a year now. I have a question, I bought a DTT valve body from one of the members on here and installed it this last weekend. During normal driving everything is just fine, TC doesnt slip at will in lockup anymore, But if you hammer down, the 2-3 shift doesnt shift. It will rev up to about 3400 rpms and just sit there until you let off, then it will shift. Also after that if you put the hammer back down after it does finally shift, before it gets to the 3-4 shift its like it just jumps right out of gear and the rpms fly up to redline, so then you let off a little bit get back into it and it shifts into 4th then locks up. Like I said this is all on a WOT run. During normal driving it shifts all gears fine. What could be my problem guys? Also, while I was in there I adjusted the bands, and switched to mobil 1 synthetic. Any help would be greatly appreciated. Thanks guys!

DieselGuyMike

Nobody has any idea?

88bird

check the kickdown/detent cable if you have it. make sure that at WOT the cable is tight and not in a bind..... that's what i would check.....

AlpineRAM

Did you install either a resistor or a voltage regulator for the governor pressure sensor when you did the VB?

Did you check your shifter linkage to be precisely on the point with the new VB?


AlpineRAM

88bird

i didn;t even think of the resistor..... Dave had me put a Diod on mine.... but he sent me a VBA (valve body assistant) later on to replace the diod..... you could give him a shout and see what he says and see if you could get a VBA from him www.goerend.com

13FOX

AlpineRam is right. DTT VB will raise pressures. Need the voltage regulator for it to work right. Also might want to get a DTT TC as well. For each VB is normally made for each type of TC DTT sells and the drivers profile.

DieselGuyMike

well I cant afford to buy a TC now, but where would I get a voltage regulator and more importantly where do I install it? I had no idea that I needed a voltage reg. I also have another question. I have a DTT TC saver, does anybody know where it plugs in? Thanks for your help guys I really appreciate it.

13FOX

Give DTT a call to purchase the voltage reg. and ask about the TC saver.

AlpineRAM

DTT Phone number
1-888-504-4002

The voltage regulator plugs into the governor pressure sensor supply. (Don't remember the pin on the PCM at the moment.)

HTH

AlpineRAM

Pinkston

My buddies dodge 1500 gas truck did the same thing after a new tranny. I am 90% sure the governor pressure sensor was the problem.

13FOX

In this case it is not a gov pressure sensor problem. A DTT VB will increase line pressures above stock and the gov pressure will go nutz because it way above stock parameters. The voltage regulator is to fool the PCM into thinking stock line pressure are in order. Also adjustment of the VR will result in slight shift paterns as well. AlpineRam can explain this much better than I.

Marcus you mind please?.

AlpineRAM

The governor solenoid has a kind of fixed duty cycle according to the output shaft speed. This duty cycle is diverting a stream of oil from the main line (line pressure) into the VB parts that control the shift pattern by speed. Those work opposing to the ones that do the throttle part. The throttle part will try to downshift when the throttle is opened and the governor pressure will try to upshift as the speed is rising. This works by simply applying one pressure to the left side and the other one to the right side of a hydraulic piston. The position of the piston determines which gear is selected. So the balance between these two pressures is crucial for the shift patterns.
The PCM applies eg 30% duty cycle for a given speed and expects somewhere between X and Y psi of governor pressure, and will correct the duty cycle to achieve the correct pressure. Since the VB raises the pressures way above what the PCM wants to see it will start to freak out a bit- it can't reduce duty cycle enough to get the pressure back to normal so it will throw you into limp mode.
Now comes the voltage regulator- normally the sensor is supplied straight 5V from the PCM and returns a voltage that goes up with pressure. The voltage regulator replaces the supply for the sensor and delivers somewhere around 4.5 V and therefore the PCM sees the lower pressures and has no cause for alarm.

Adjusting the voltage regulator will change the shift points a bit.

Naturally it's also possible that the pressure sensor is bad or the solenoid is bad or dirty, but you will need the regulator anyway with a DTT VB.

HTH

AlpineRAM

B18B1LS1

I didn't do any of that with my Garmon valvebody and it SEEMS to work fine. Could it do even better with a voltage regulator too? The shifts are already nice and crisp, but I would like some higher shift points!

AlpineRAM

I'd contact the vendor of your VB- I don't know Garmon's VB so I don't know what he did to work around the governor pressure stuff.
You can adjust the light throttle shift points on the VB:

http://www.dieseltrans.com/phpBB/viewtopic.php?t=68

AlpineRAM

kevellis32

Where is the kickdown/detent cable located on the 47re?