Ally shift points

[Mike]

From what I have tried on my own truck it varies quite a bit even from stock tune to stock tune. On my stock tune raising the shift points alone didn't work, it gave it a really bad hangup between the gears. I had to change the taps to get rid of it and it shifts smooth as can be now, however on Coreys truck which is an 02 changing the shift points alone it shifted perfect all the way up to 4300. But shifting it that high didn't help the perormance, and cause a lot of popping that sounded like the valves floting. I try to set the shift points to where when it shifts it falls back to the peak torque. I've tried about every imaginable rpm to shift at on mine and 3600 is the best I've found, but I don't have heads, cam and all that stuff. Just a tired LB7 and SC4 with 128,000 mi.
My opinion is anything over 3600 on a stock engine is not going to gain much if any power, but shifting at 4k makes mine sound awesome. I think with enough research the tranny can be tuned to work very well, but I think a lot of tables are not there that we need to make it do Exactly what we need it to. Thats enough for now, my fingers are tired already...so thats my opinion for what it's worth.

I was going to try to post a before and after screenshot of the difference before and after I changed the tune but I couldn't figure it out so we'll all have to go by mikes word because he's seen the logs, I think Simon has seen a couple too. I had a hangup bad enough to bounce to mph about six mph back and fourth when it shifted that I seem to have completly fixed so far. Going on 6500mi without changing it and tranny is in one piece so far.(knocking on wood) and shifting great.

Thanks Kevin, knew you'd chime in. Just took a bit of asking. lol

 

[Bluemax]

Hope they used lube :joker: Oh well, there loss sounds like.

I'm telling you it was dry and without mercy, I'll never answer a question from those guys with my thoughts again.

 

[Kat]

Pat, do you have ported heads and a cam in Casper?

The engine that is in Casper now just has heads.

 

[McRat]

It's not the heads/cam that causes the powerband to move up.

It's the tuning and turbocharger. Big chargers like RPM. And I de-torque my tunes deliberately.

Knock-on-wood, we've actually broken very little stuff on Casper. When others claim they need Lenco transmissions and beefy axles to live at 700hp, we are happily spinning our problems away.

 

[Bluemax]

Does the de-torquing come into play for a pulling track? In my case I tried to use the higher rpms to lessen the strain on internals and I couldn't get the ground speed that I do with the lower rpms. It just seemed to fall off I assume from lack of fuel at the higher rpms.(but it sounded cool:cool2 Is there any way to overcome this on a mostly stock truck? Or is there not enough strain on the motor to worry about at 500hp or so?

 

[MAXLLY]

I'm not doing anything special, just moving the shift points to 4000 rpm, because that's where I'm making the power.

Keep in mind I went over 120mph on fuel with factory shift points. I'm shifting higher to cut back on torque to save both transmission parts and engine parts.

When Mike tore down Casper's Allison after ~70 quarter mile passes running in 10 second territory, no RPM related damage happened. The trans would have lasted another 70 passes it looked like. 140 passes might not seem like alot, but the other Dmaxes running similiar power get only a couple of passes out of an Allison before it returns to kit form.

Is it shifting at 4000 rpm? No RPM related damage congrats! What damage did the trans reflect and would you be willing to tell us Mcraters why and how to avoid whatever damage the trans did reflect? Please.

Retail cost being roughly 5-6k (SC-4) it would be a big money saver for the guys who are gonna push the envelope a little and want to avoid breaking trannies.

 

[Kat]

Is it shifting at 4000 rpm? No RPM related damage congrats! What damage did the trans reflect and would you be willing to tell us Mcraters why and how to avoid whatever damage the trans did reflect? Please.

Retail cost being roughly 5-6k (SC-4) it would be a big money saver for the guys who are gonna push the envelope a little and want to avoid breaking trannies.

Here is the results of the last time Mike looked at Casper which was after TX

http://www.dieselplace.com/forum/showthread.php?t=190167

 

[Mike]

Here is the results of the last time Mike looked at Casper which was after TX

http://www.dieselplace.com/forum/showthread.php?t=190167

Nice info, Thanks Kat.

 

[Turbotug]

I must have missed class the day they talked about Alli tuning.

I can't seem to access the TCM for the life of me!

 

[Bluemax]

Start just like you are going to read the ecm tune except when the box pops up after you click on read controller make sure it has allison tcm selected if not click the dropdown box and select it. Then read it out like an ecm.

 

[Turbotug]

Ahhhh, Thanks!

 

[LarryJewell]

Start just like you are going to read the ecm tune except when the box pops up after you click on read controller make sure it has allison tcm selected if not click the dropdown box and select it. Then read it out like an ecm.

:stupid:

 

[Turbotug]

Thanks again guys. I saved the stock tune and then fiddled with the WOT shifts for RPM. We'll have to see how they do on the way home today.

One thing I was hoping to find was some tables for grade braking. Is this not in the TCM? For some reason my truck has a bad habit of down shifting to 4th around 50mph. Like if you're on the freeway and have to let up for someone to merge. I don't touch the brakes and am only off the gas for a few seconds, maybe only loose 5mph and then it shifts and I'm coasting along at 2500prm. All it takes to get it back to fifth is a little go pedal, but it's annoying!

 

[SIKDMAX]

Is it safe to turn up the 4-5 shift in t/h a few hundred rpm? Id like mine to take 4th up to at least 3000 in t/h... its shifting as low as 2100 sometimes now and really falls on its face into 5th. Anyone here done just the 4/5 and how far have you taken it?

 

[Bluemax]

Thanks again guys. I saved the stock tune and then fiddled with the WOT shifts for RPM. We'll have to see how they do on the way home today.

One thing I was hoping to find was some tables for grade braking. Is this not in the TCM? For some reason my truck has a bad habit of down shifting to 4th around 50mph. Like if you're on the freeway and have to let up for someone to merge. I don't touch the brakes and am only off the gas for a few seconds, maybe only loose 5mph and then it shifts and I'm coasting along at 2500prm. All it takes to get it back to fifth is a little go pedal, but it's annoying!

I wish I could get mine to do that sometimes. Mine will not downshift until 1500rpm unless you are at 3\4 throttle and let off and hit the brake quick for some reason. I'll send you the one I'm using if you'd like to try it. Maybe we could try each others and see if we have the same results.:dontknow:

 

[Bluemax]

Is it safe to turn up the 4-5 shift in t/h a few hundred rpm? Id like mine to take 4th up to at least 3000 in t/h... its shifting as low as 2100 sometimes now and really falls on its face into 5th. Anyone here done just the 4/5 and how far have you taken it?

I have done it and haven't had any problems. I would suggest getting a log of the rpms when it shifts, open the tranny tune pull up the shift table for part throttle 4-5 t\h upshift rpm, move the rpms at that throttle position up by a percentage until you get it where you want it and make sure you move the part throttle 4-5 t\h speed table up the same percentage at the same places to make sure everything is still working together. Baby steps and some time and it'll click off shifts just like you want it to.

 

[SIKDMAX]

I have done it and haven't had any problems. I would suggest getting a log of the rpms when it shifts, open the tranny tune pull up the shift table for part throttle 4-5 t\h upshift rpm, move the rpms at that throttle position up by a percentage until you get it where you want it and make sure you move the part throttle 4-5 t\h speed table up the same percentage at the same places to make sure everything is still working together. Baby steps and some time and it'll click off shifts just like you want it to.

Thank you sir! Appreciated!