Engine/Transmission (1998.5 - 2002) How do I increase the 3 to 4 upshift point?

[BILLVO]

I have a BD vale body and converter and pressure lock. I have adjusted the throttle valve cable shorter to increase the shift points but all it seems to affect with any signifigance is the 1 to 2 and 2 to 3 shift points. The one I really want to Up the shift point on is the 3 to 4 shift It shifts into OD at 45-50mph on normal driving then with all my mods it Dogs and egts climb big time. I would like it to not grab OD until at least 55-60 on light throttle accel.



My question is there a way to do this without affecting the lower shift points?Is there an adjustment in the valvebody that can be made?What would the side effects be while trailer pulling as the light modulation would be gone and it would be harder on the guts of it I suppose?

 

[RobertP]

I have a BD vale body and converter and pressure lock. I have adjusted the throttle valve cable shorter to increase the shift points but all it seems to affect with any signifigance is the 1 to 2 and 2 to 3 shift points. The one I really want to Up the shift point on is the 3 to 4 shift It shifts into OD at 45-50mph on normal driving then with all my mods it Dogs and egts climb big time. I would like it to not grab OD until at least 55-60 on light throttle accel.



My question is there a way to do this without affecting the lower shift points?Is there an adjustment in the valvebody that can be made?What would the side effects be while trailer pulling as the light modulation would be gone and it would be harder on the guts of it I suppose?

i see you have a smarty, go and put in a smaller tire size see if this helps.

 

[AKAMAC]

I know what you mean! I have gotten to know when conditions will require manual L/O of OD. I hope you get an answer.

 

[BILLVO]

Any transmission guys out there who can give me a direction?

 

[paulb]

The 3-4 shift is controlled by the computer and not the trans. I believe there are some controllers out there that will change the 3-4 shift point as well as the lockup. I'm not sure who makes them though, or how well they work. I just use the OD off button, if I don't want it to go into OD.



On another note, be careful adjusting the throttle valve cable. Not only does it change the 1-2 and 2-3 shift points it also changes the governor pressure. If you lower the pressure to much you can burn clutches.



Paul

 

[BILLVO]

Thanks Paul thats what I was looking for.

Bill

 

[zstroken]

Adjust the TPS make it appear you are giving more throttle.

 

[BILLVO]

Adjust the TPS make it appear you are giving more throttle.

Do you mean the throttle valve cable? I adjusted that already. Or did you mean the Throttle position sensor? how do you do that one?

 

[zstroken]

I am unsure on the 24V. I have a manual, and never have played with them. On the 12V you can make the computer think you are giving more accelerator that you actually are.

 

[Devan Manis]

not so on a 24v, the tps, is what controls fueling, if you make it appear you were giving it more pedal than you want, it will give it more pedal than you want.

 

[BILLVO]

Under normal driving conditions 3rd gear is just a blip as it seems to go straight to od then lockup within 2 seconds then the smoke rolls. I would like it to go into 3rd and stay until speed and pressure rise like in 1 and 2 feels like 3rd doesn't even exist unless you are getting on it but even then it is in and out of 3rd real fast.

 

[FTwardoch]

Under normal driving conditions 3rd gear is just a blip as it seems to go straight to od then lockup within 2 seconds then the smoke rolls. I would like it to go into 3rd and stay until speed and pressure rise like in 1 and 2 feels like 3rd doesn't even exist unless you are getting on it but even then it is in and out of 3rd real fast.

Sounds like you're describing the 'stacked shift' where it goes from 3rd to Overdrive and TCC lockup at once. Pretty annoying, isn't it? I've tried three things, with some success but it still happens. First was adjusting the cable (which my transmission guy did for me) with little to no improvement. Then he upped the pressure in the transmission (again, not much improvement). Third thing was checking and then resetting the APPS (NOT the 'unplug battery' thing, the actual reading of the voltage followed by the physical adjusting of the APPS). This helped a lot (mine was way off, reading . 39V with a spec on the APPS of . 535V) but it STILL does it. I personally think it's a SMARTY thing since it never ever did it with just the Edge EZ I had and started immediately after installing the Smarty software. I called it a 'flat spot' when I first experienced it and got Marco/Bob W involved) It does it on any software level but most obviously on #9 (where all the fun is). Appears that the more power you have the less pedal you need to push so the APPS is seeing this and shifting accordingly. So maybe 'overadjusting' the APPS is worth a try... ... ... ... . but that seems counterintuitive to wanting it to run 'properly'. In my old gasser days I was into TPI motors (Tuned Port Injection Vette/Camaro motors) and did play some with TPS voltage manipulation so it's not unheard of.



Decreasing tire size was mentioned earlier... ... ... ... . hmm, interesting thought (but the downside is your speedo would be off again)... ... .....



Keep the thoughts coming guys, I'd love to solve this once and for all.



Maybe it's just a worn out APPS fluctuating with flat spots at certain throttle level positions that needs replaced (and the reset only helps a little?)?

 

[BILLVO]

More like it goes from 2nd to OD then Lockup all at once skipping 3rd. It has always done it even when it was all stock but with all the mods it is just highly amplified now. I have all the transmission pressure enhancing things done already like converter valvebody and pressurelock all from BD. I don't really want to try the tire size adjusment with the smarty as I have read it isn't accurate and I don't want to contribute to the local government officials. Maybe I will try and do the apps voltage check.

 

[hdtrukn]

I am trying to track down info on an adjustable TPS.

By using a variable resistor in cab you are supposed to be able to move your shift into overdrive up or down.

Any one else heard of it ?

Thx

Scott

 

[BILLVO]

I am trying to track down info on an adjustable TPS.

By using a variable resistor in cab you are supposed to be able to move your shift into overdrive up or down.

Any one else heard of it ?

Thx

Scott

I would be interested in this also. Someone here has a thread with a link to a truck on e-bay with one of these in the vehicle description. It also had 2 switches controling lockup clutch. I am thinking of this also as I think it would help. If anyone can chime in with more info on where to get instructions on how to do this it would help out a lot.

 

[SnoKing]

If you would have gone with DTT, their Smart Controller lets you set the 3rd to OD shift point to anything you want. So, just start using the lockout button, in a week or two it will be natural to you. SNOKING