Hard shifting

[Obsessed]

I once had the Diablo installed on my TBSS. It made the shifts more firm and run just a little better. I have since uninstalled it and will be getting a "real" tune. Since uninstalling the Diablo, it seems my shifts are insanely hard. I am wondering if it kept the TM zeroed, instead of really putting it back to factory settings.

I cannot get this tune soon enough. Hopefully when it's tuned the person will find the tables and let me know what they were set at and get it fixed before something happens to my transmission.

[ghoster]

I would think that zero'ed out TM would be really really bad wouldn't it?:confused:

[BLK60SS]

Yeah it would be a bad thing. Ghoster, it's come to light that the Diablo tune does indeed zero out the TM tables. Not sure if it was posted here or TBSS.

[ScarabEpic22]

I would think that zero'ed out TM would be really really bad wouldn't it?:confused:
Yeah, but it can only control the ECM anyway. Chris said something about Diablo zeroing out the TM tables in the ECM (TCM still has full TM) because they cant touch the TCM.

[ghoster]

Yeah, but it can only control the ECM anyway. Chris said something about Diablo zeroing out the TM tables in the ECM (TCM still has full TM) because they cant touch the TCM.

Ok...so why are there TM tables in both the ECM and TCM?? Now you guys are just trying to confuse me!:D

[Obsessed]

Not sure how it did it, but it did. Someone checked the tables after the Diablo was installed and it had them zeroed.

Since hearing that, I will no longer recommend that Diablo to anyone. I am wondering if it didn't somehow keep the settings the same, if so, Diablo Sport needs to address the problem and fix it promptly.

[ScarabEpic22]

Ok...so why are there TM tables in both the ECM and TCM?? Now you guys are just trying to confuse me!:D
Yea, there are different tables in both computers, have no idea why it was done that way.

I know for the I6 PCM that there are a few parameters in the engine section and another few in the transmission (via EFILive), so I assume the SS ECM and TCM are pretty similar (as is the 5.3L V8s ECM/TCM too).

[GTPprix]

Well what they did was they zeroed the table that tells the ECM how much timing to pull during a TM event.. This turns it ALL off (about 10 different modes). Not exactly a wise idea IMHO.. I had a hunch this was the case when people were saying thier shifting was improved when they had no TCM support (I've posted that a few times) this just confirmed it..

[ghoster]

ouch....that sounds like a very dangerous (for your transmission) thing to do. Can't imagine why they would do that, unless somebody actually requested it.:confused:

[GTPprix]

Oh sorry, I didnt attempt to address your problem :)

The TCM has whats called TAPS (Transmission Adaptable Pressure System) cells that learn to adjust (lower or raise) pressure to meet a criteria of whats typically referred to as "Commanded Shift Time". (Yes these tables exist in a little different fasion in the T42 Trans Controller, but they arent 100% the same as the old P59 PCM)

Anyhow, basically what these tables consist of is a bunch of cells that adapt the shift pressure based on the commanded shift time and the base pressure thats set in another table for whichever mode the trans is in.

My guess is with TM removed the extra slippage created during a shift event caused the TAPS cells to bump up the pressure to meet the commanded shift time thus resulting in firmer shifts even AFTER the stock calibration was put back in since these cells are in the TCM.

My guess is if you have someone with a Tech 2 reset the TAPS cells it'll be just like stock and you should be in the clear :)

[bass222000]

Now im worried bout my Diablo tune. So I programmed mine back to stock. Not as quick anymore but better than the tranny popping. As soon as I can acquire a few "down days" for the TBSS, im sending the ECM and TCM out to Chris for the Vector tune. Now I have a 300.00 predator "paper weight"!!!

[Obsessed]

Now im worried bout my Diablo tune. So I programmed mine back to stock. Not as quick anymore but better than the tranny popping. As soon as I can acquire a few "down days" for the TBSS, im sending the ECM and TCM out to Chris for the Vector tune. Now I have a 300.00 predator "paper weight"!!!

Maybe you could contact Diablo Sport about it and see if they can give you a tune that won't totally turn off TM. In fact, if you found the original table for it, install the Diablo tune, then go in and changed the TM table back to normal or close to, you would have a decent and safe tune.

[ADM PERFORMANCE]

I was wondering when taps would come up in conversation.:)

We will now get to have fun with this one!:yes:

[Liquiddi]

very interesting. I could have sworn mine shifted better when I installed the diablo. Question is how do you know if going back to stock returns the TM????

[Liquiddi]

diabo sucks. Went back to stock and the TM is back. Diablo = broken tranny quickly down the road. $300 paper weight.

[FastBlueSS]

Why don't you people who are scared to use your Predator take it up with Diablo Tech support? It's free, and you can ask all these questions directly to them. Believe me you will hear much more intelligent answers than what you are hearing on this forum!:yes:

[vetruck]

:iagree: I'll ask Diablo about it to see what they say. I just can't imagine DS risking peoples trannys for a little better acceleration. Is it supposed to be the same for the Vette, GTO, and SSR?

[vetruck]

I have not e-mailed diabo yet but I will today. Anyway, I got the r99 revision off the website and put it in the truck yesterday. Let me just say that the shifts are all smooth now. Still shifts like a performance truck but with a smooth transition from 1-2 and 3-4 which were quite rough and clunky before at low rpms. The 1-2 also used to hang a second or two sometimes before fully shifting into 2nd but that has stopped. I've only driven it 50 miles so far but I think they have done something with the TM. So before trashing your Predator, download the current revision and see how it feels, I think you'll be impressed like I was.