VDH Trans tuning?

[Aaron S]

My truck is mostly stock performance wise with just swamps stage 1 injectors. The trans is stock at 140,000 miles and the truck has 35 inch tires.

Is it possible to have quick, clean tranmission shifts with the vdh pcm when the truck is in higher hp settings?

 

[Fl Stroker]

Yes you can. Give Dave at Swamps a call. I had 0 issues when I had my stock tranny.

 

[Aaron S]

That is who my chip is from. They have said it may not be possible to achieve what I feel is acceptable shifting without modifying the trans mechanically.

I just installed a chip from them with there latest software. With it in the highest tune and one below the shifting has a slip and bang quality to it.

Im not trying to knock Swamps. Just wondering if other tuning platforms can offer solutions or what other solutions are out there.

Thanks

 

[Dieselboy.]

If I were you I would throw a better valvebody in. Or you will burn up a stock trans.

 

[CurtisF]

That is who my chip is from. They have said it may not be possible to achieve what I feel is acceptable shifting without modifying the trans mechanically.

I just installed a chip from them with there latest software. With it in the highest tune and one below the shifting has a slip and bang quality to it.

Im not trying to knock Swamps. Just wondering if other tuning platforms can offer solutions or what other solutions are out there.

Thanks

Just keep in mind that it might not be the trans tuning....

There's only so much tuning can do if the trans itself is unable to handle the power in the first place.

A hurting stock trans + extra power = funny shifting.

And if the trans is already hurting, a valve body won't help either.


Just food for thought. Not saying that is absolutely the case with your truck, but it's certainly possible and even very likely with 140K+ on a bone stock trans behind an engine with upgraded injectors.


On the flip side, VDHx trans tuning does like to freak out on the torque converter lockup when you're running higher HP tunes. There's a delay that needs to be turned off to fix the problem. But it doesn't affect other gears at all, only the T/C lockup part. So if your problem is the upshift and not the T/C lockup, then it's not the tuning.

 

[DP-Tuner]

My truck is mostly stock performance wise with just swamps stage 1 injectors. The trans is stock at 140,000 miles and the truck has 35 inch tires.

Is it possible to have quick, clean tranmission shifts with the vdh pcm when the truck is in higher hp settings?

Yes done 8 years ago. Like many other codes we continue to find how to make them shift even better. Mechanical upgrades are going to be a must if you want to beat on your truck or work it harder.

I would look at your speedo to make sure it is calbrated to the 35's. Could be what your issue is.

 

[Aaron S]

The only two shifts that are good are the tc locking up and the shift after that into overdrive. Its the 1-2 and the 2-3 shifts that are weak/slow.

Thanks for the help so far.

 

[907DAVE]

I would look at your speedo to make sure it is calbrated to the 35's. Could be what your issue is.

What does the speedo have to do with shifting?

The tunes can be adjusted for the tire size...regardless of what the speedo displays.

 

[DP-Tuner]

What does the speedo have to do with shifting?

The tunes can be adjusted for the tire size...regardless of what the speedo displays.

A great deal.

On the 1999-2003 7.3 the speedo information is not in the PCM. It is in the ABS module. Bigger tires mess up the speedo and throws off the shift points. The Rev's per mile information is in the PCM on the late 2003 6.o's and up. The OBS guys can recalibrate the speedo from the tripometer.

At one time I did tune for bigger tires, but it is not 100%. Once you go to a smaller or bigger tire all tunes have to be redone.

Jody

 

[907DAVE]

Hmm....






Then what do the Tire Size and Rear Axle Ratio parameters do????



By changing the Rev/Mile in the PCM, the shift point and speed limiter functions will be affected.....not so much on an OBS...but it pretty sensitive on a SD. Yes, the speedometer will still be incorrect as this IS as function of the ABS module, but the speedometer itself has no bearing on the shift points (in a SD).

 

[DP-Tuner]

Hmm....






Then what do the Tire Size and Rear Axle Ratio parameters do????



By changing the Rev/Mile in the PCM, the shift point and speed limiter functions will be affected.....not so much on an OBS...but it pretty sensitive on a SD. Yes, the speedometer will still be incorrect as this IS as function of the ABS module, but the speedometer itself has no bearing on the shift points (in a SD).

Shift points are all throttle position and speed.

If the speedo is incorrect the shift points will be off. See this all the time when guys call me when there tunes don't feel right and we discover they have 37's and their speedo is off 5 mph. They get the speedo recalibrated and all is in sync.

If this was not the case then Superlift would have never come out with a truspeed or Auto E would not have the speedo recalibration feature up to 38's.


Jody

 

[907DAVE]

Lil' bob and weave action......lol.

Do you not understand the relationship between PCM and the speedometer....?

So you are telling me that if the speedometer was inop because of a cluster issue, the truck would never shift because its reading wrong???

 

[DP-Tuner]

Lil' bob and weave action......lol.

Do you not understand the relationship between PCM and the speedometer....?

So you are telling me that if the speedometer was inop because of a cluster issue, the truck would never shift because its reading wrong???

Yes I fully understand.


Let me see if I can explain it this way.


Bigger tires throws off the signal to the ABS which throws off the information sent to the PCM and Speedometer/odometer.

No I am not telling you that.

Try this on your VDH truck. Go unhook your ABS module and go drive the truck. Come back an tell me how it shifted.



Jody

 

[907DAVE]

So why not just change how the PCM interrupts this "false" information to make your customers happy, instead of sending them away telling them they need to spend another $200 plus to make your tunes shift right?

Just curious?

 

[DP-Tuner]

So why not just change how the PCM interrupts this "false" information to make your customers happy, instead of sending them away telling them they need to spend another $200 plus to make your tunes shift right?

Just curious?

You can not control the signal coming from the ABS to the PCM and Speedo/odometer


When did recaliibrating become $200 to do this. I charge $45 at live tuning events and when you get the live tuning its free. Geez!

I rarely tell anyone to go to the dealer to get this done. If it's their only resource then I do. If I was to do this is in all the tunes it would take me hours if they have a lot of tunes. It's not just hitting one button and being done. Too many things to do and it's not 100% accurate. I won't do it anymore because recalibrating the speedo is more accurate. Also, I do this the save my customers from having to buy custom tunes.


Jody

 

[907DAVE]

Thanks!