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View Full Version : Need Help with TM on 2009 4.8L Pickup



Performance SS
06-21-2014, 07:14 PM
Been tuning LT1 and LS cars for some time, but having difficulty with a friends 2009 4.8L 1500 Chevy Pickup. It will not spin the tires no matter what I do. I have tried several different attempted modificiations to the TM tables in both the Engine and TCM with little to no success. Not familiar with "Tip-in Torque Reduction (ft-lb) Vs. Torque Vs. TPS for all gears. Do I zero these tables or max them out to get rid of TM. I'm using TunerCat, anyone with a .cal file with successful TM removed would be appreciated for comparison or steering me in the right direction.

Thanks

dave w
06-21-2014, 08:54 PM
Would it be possible for you to post the original / stock unmodified .cal file?

dave w

Performance SS
06-21-2014, 09:09 PM
Dave - Thanks for your respone. I'm currently at work, will have to get to tuning laptop so that I can upload .cal files. Will do so then.

Thanks again for any assistance.

Performance SS
06-21-2014, 09:45 PM
I hope I did this correctly. I attached the two files in stock form.

dave w
06-21-2014, 10:05 PM
I have downloaded the files. I'm more familiar with the the Before 2007 LSx systems. I'm sure you have already tried the setting in the picture below?

dave w

Performance SS
06-21-2014, 10:16 PM
I've tried several combinations, but I'll go over those settings once I get the truck back and try several things again. I just hate trying without understanding the function. Naturally that's usually the way we have to learn with trial and error, but TM has so many variables that lend to the possibility many combos and errors.

Performance SS
06-21-2014, 10:32 PM
I looked back at what i programmed. I had the Calibrations Options as you noted, but I didn't have the TCS Enable temp maxed out. It was still at -40. That would not allow TCS even with it ON, I would assume?

dave w
06-22-2014, 01:41 AM
I looked back at what i programmed. I had the Calibrations Options as you noted, but I didn't have the TCS Enable temp maxed out. It was still at -40. That would not allow TCS even with it ON, I would assume?

I think the challenge with programming is knowing which direction the parameter is enabled. Is the parameter enabled above or below a set point? My thinking ... the TM set point was originally set to -40C so TM would ALWAYS be ON. My thinking ... TM set to 255C the TM would ALWAYS be OFF.

dave w

Performance SS
06-22-2014, 12:01 PM
I think the challenge with programming is knowing which direction the parameter is enabled. Is the parameter enabled above or below a set point? My thinking ... the TM set point was originally set to -40C so TM would ALWAYS be ON. My thinking ... TM set to 255C the TM would ALWAYS be OFF.

dave w

That could very well be the correct way of thinking! I should have access to the truck again on Monday or Tuesday, I'll post the results when complete.

Thanks again!

LRT
06-22-2014, 09:30 PM
Does the truck have a switch in the dash somewhere to disable the TCS ? If it does, and you have disabled the TCS with this switch, and it still won't spin the tires, then the issue could be with BTM and / or abuse mode settings.

Performance SS
06-22-2014, 11:01 PM
Does the truck have a switch in the dash somewhere to disable the TCS ? If it does, and you have disabled the TCS with this switch, and it still won't spin the tires, then the issue could be with BTM and / or abuse mode settings.

LRT - Yes, this truck has the Disable Switch on the dash and it performs basically the same with the TCS enabled or disabled. I zero'd the Abuse Mode Tq Reduction vs. RPM tables. BTM is not registering with my brain. Could you clue me in on the meaning of BTM? Here's the latest revisions that I intend to try on the truck tomorrow. I have tried several things in the attempt to remove TM, so I've taken the shotgun method on this tune to this point!

LRT
06-23-2014, 12:07 AM
BTM = Brake Torque Management. Try this tune ...

Performance SS
06-23-2014, 01:47 AM
BTM = Brake Torque Management. Try this tune ...

LRT - Thanks for taking the time to help! I did a comparison report against the tune you sent and the one I had prepared to try next listed above : PSS 06 Tip. It appears I have the 3 changes you suggested covered. Should get the truck tomorrow or Tuesday and give it another try. We post the outcome and finding.

Thanks again.

roughneck427
06-24-2014, 12:17 AM
I just dealt with this last week in EFI live it has a few spark tables
Maximum Spark Retard
Power Reduction MIN timing
Min final timing

John added them last week as i was having same issues.Ask for an update to that vdf all i did was change shift points and messed with these tables and it barks second gear most changes were to min final timing

Performance SS
06-24-2014, 03:10 AM
I just dealt with this last week in EFI live it has a few spark tables
Maximum Spark Retard
Power Reduction MIN timing
Min final timing

John added them last week as i was having same issues.Ask for an update to that vdf all i did was change shift points and messed with these tables and it barks second gear most changes were to min final timing


Roughneck - Is the vehicle you are speaking of a 2009 4.8L? I just flashed it with the suggestions from those that made suggestions, along with some ideas of mine. Nothing changed the performance of the truck. It still will not spin the tires from a stop, with or without TCS on and AC off. I'm going to forward your suggestions to TC and see what he can come up with. Thanks for your input, everyone's input is appreciated.

roughneck427
06-24-2014, 03:57 AM
It was on a 2011 5.3 same vdf as a 2009

Performance SS
06-27-2014, 04:09 AM
It was on a 2011 5.3 same vdf as a 2009

Roughneck - TC did update the vdf for me with the added tables. I did not have the 2009 4.8L, so I've been playing with my 2012 (which shares the same vdf) and it does seem to respond to the changes. The final timing table does seem to be the biggest game changer, but the 2012 5.3L is very sensitive to timing changes. I'm still tweeking it when I have time and hope to have a attempt ready for the 4.8L truck soon. Thanks again to all and I'm update again once I get the truck back.

roughneck427
06-27-2014, 04:49 AM
Yeah min final timing helps the most on the 6 speed trucks and how I found out on this is I used efi live on my Pontiac G8 I tried same settings I used on my car on a truck and your right they are sensitive it shifted way to hard had to trim it back some

Performance SS
06-27-2014, 11:13 PM
This is a test tune on my 2012 5.3L. It should be close to what you were dealing with.

Thanks,
Steve

Performance SS
07-07-2014, 06:00 AM
Just an update. Truck responded well to raising the minimum final timing, but still is lame from a dead stop. Not sure if I'm missing something or expecting it to be able to burn the tires down and it's simply not capable? Not giving up at this point, but haven't had something whip me like this in awhile.

doctortuned
07-07-2014, 06:05 PM
The stall speed for the torque converter is built low. Tuning helps out. But just a tune your not going tune able to roast the tires. I always recommend a higher stall converter to be able to spin the tires like your asking. That way it will be right in the power curve when you go wot.

Performance SS
07-07-2014, 10:36 PM
The stall speed for the torque converter is built low. Tuning helps out. But just a tune your not going tune able to roast the tires. I always recommend a higher stall converter to be able to spin the tires like your asking. That way it will be right in the power curve when you go wot.control

That makes sense. I keep thinking GM is regulating the low end performance via ECM, but I guess it's just as possible they lowered the stall for a direct control. Thanks for helping me open up to other possibilities for limited performance. It makes sense!

Hog
07-08-2014, 08:52 PM
I doubt GM lowered the TC stall on purpose, the issue is its a GEN 4 4.8 engine that makes very little off idle torque. If you hada 5.3 the same 4.8 TC would stall a bit higher due to the increased torque of the 5.3.

peace
Hog

Performance SS
07-08-2014, 10:04 PM
I doubt GM lowered the TC stall on purpose, the issue is its a GEN 4 4.8 engine that makes very little off idle torque. If you hada 5.3 the same 4.8 TC would stall a bit higher due to the increased torque of the 5.3.

peace
Hog

Very possible. I have a 2012 with the 5.3L and it's not much off idle either. Still not sure if it can be tuned out or if it simply doesnt have the low end torque as you mentioned.

Thanks!