4L60E torque management

[slicks2003]

Does the 2003 SSR 4L60E have torque management ?

[slicks2003]

I answered my own question, it does have TM from what I found on the internet.

[Mike in AZ]

Originally Posted by slicks2003

Does the 2003 SSR 4L60E have torque management ?

The entire control system has torque management through it.

The computer takes engine rpm, transmission gear, inlet air temp, coolant temp, mass airflow, vehicle speed, front wheel rotational speed, rear wheel rotational speed and throttle request to calculate what position to regulate the throttle body to. Your gas pedal command to the system is nothing more than a request to the computer for power. The computer decides what to give you. You wil not get full throttle opening at 0 mph. You will get a "tip-in" rate of change to a governed amount of torque determined by the computer inputs and the "look-up tables" in the computer system memory. Somewhere about 15mph, you will have the throttle body full open.

You will also get a momentary ignition retard and a partial throttle body closure at each gearshift. Momentary is measured in milliseconds.

All this stuff is done to provide "torque management" of the drive train. If you didn't have it, there would be transmission parts littering the street and driveline reliability would be seriously compromised. Torque management is a good thing...... it keeps us from doing stupid things and scattering hardware. This is why we need to be very careful when using aftermarket tuning kits. You can take out a lot of torque management and make the truck snappy, but you need to be sure you don't take out so much that you compromise component life.

Don't confuse Torque Management with Traction Control. They are somewhat related because of the inputs used, but the similarity stops there. Traction control is derived from the anti-lock braking system and measures rear wheel spin. When you get over the commputer's threshold for spin, it reduces throttle body position.... regardless of gas pedal position.

Hope this helps,

Mike

[slicks2003]

Originally Posted by Mike in AZ

The entire control system has torque management through it.

The computer takes engine rpm, transmission gear, inlet air temp, coolant temp, mass airflow, vehicle speed, front wheel rotational speed, rear wheel rotational speed and throttle request to calculate what position to regulate the throttle body to. Your gas pedal command to the system is nothing more than a request to the computer for power. The computer decides what to give you. You wil not get full throttle opening at 0 mph. You will get a "tip-in" rate of change to a governed amount of torque determined by the computer inputs and the "look-up tables" in the computer system memory. Somewhere about 15mph, you will have the throttle body full open.

You will also get a momentary ignition retard and a partial throttle body closure at each gearshift. Momentary is measured in milliseconds.

All this stuff is done to provide "torque management" of the drive train. If you didn't have it, there would be transmission parts littering the street and driveline reliability would be seriously compromised. Torque management is a good thing...... it keeps us from doing stupid things and scattering hardware. This is why we need to be very careful when using aftermarket tuning kits. You can take out a lot of torque management and make the truck snappy, but you need to be sure you don't take out so much that you compromise component life.

Don't confuse Torque Management with Traction Control. They are somewhat related because of the inputs used, but the similarity stops there. Traction control is derived from the anti-lock braking system and measures rear wheel spin. When you get over the commputer's threshold for spin, it reduces throttle body position.... regardless of gas pedal position.

Hope this helps,

Mike

GREAT information and I totally understand.... I also now realize why it does not act like other auto's I have had.

Thanks Mike!

[Mike in AZ]

Originally Posted by slicks2003

GREAT information and I totally understand.... I also now realize why it does not act like other auto's I have had.

Thanks Mike!

No worries. I'm a controls engineer for the turbine engines that push business jets around the skies. It's a professional fascination.

The traction control system is really crude and will catch you off guard when you do a little wheelspin. I think GM really missed the mark on this one. It's abrupt and everyone needs to "test" it at least once to know what to expect in the wet or on some snow. (neither of which happens much in Phoenix) If you have enough power to get some wheelspin when the tranny shifts into second, you will get it too. Again, it's pretty abrupt and feels like the engine falls on its face. I'm sure it has saved a few situations, but........

Have a great day,

Mike

[MnMsToy]

Originally Posted by Mike in AZ

No worries. I'm a controls engineer for the turbine engines that push business jets around the skies. It's a professional fascination.

The traction control system is really crude and will catch you off guard when you do a little wheelspin. I think GM really missed the mark on this one. It's abrupt and everyone needs to "test" it at least once to know what to expect in the wet or on some snow. (neither of which happens much in Phoenix) If you have enough power to get some wheelspin when the tranny shifts into second, you will get it too. Again, it's pretty abrupt and feels like the engine falls on its face. I'm sure it has saved a few situations, but........

Have a great day,

Mike

Excellent info Mike. Does the same apply to the 6-speeds in regards to the TC?

[Mike in AZ]

Originally Posted by MnMsToy

Excellent info Mike. Does the same apply to the 6-speeds in regards to the TC?

Two things about the 6-speeds........

1) There is no traction control. Owners of 6-speeds don't have the switch on the console.

2) The torque management software is still in there from the automatics. Every 6-speed owner should get his software modified to remove most of the stuff. Some of the "tip-in" and "tip-out" speed on throttle body positioning should remain, as it aids drive-ability and a few other parameters that need to be left alone.... but there is a LOT of stuff that can be taken out....... I think there are some old threads from Joe Delano about this.

Oh.... one more difference about 6-speeds........ They are the only SSRs with a locking steering column.

Mike

[xoxoxoBruce]

Originally Posted by Mike in AZ

Oh.... one more difference about 6-speeds........ They are the only SSRs with a locking steering column.

Mike

Huh? Didn't someone have a problem with the switch that tells the computer the auto-trans is in park, so it wouldn't release the solenoid that allows the key to turn to lock? I though that was to prevent the column from being locked while the truck was possibly moving? Guess it's just to make sure you don't leave the truck without the trans in park then. I'll be damned, learn something new everyday.
Thanks, Mike.