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Discussion Starter #1
i put on a juice w/ attitude last weekend and so far love it. it is amazing what $800 and 1 hour will get you these days
my problem is at cruising speed the attitude will flash between 0, .6, .7 on the slip even when the tcc is locked, it happens fast enough that if you weren't watching it closely you wouldn't see it because it stays on 0 most of the time, it looks like a glitch but it has me scared because i cant afford to upgrade the tranny and need this truck to last a long time. btw i am running #2, defuel all shifts, lowest low boost fuel setting.


thanks for any replys. Edited by: rocksam
 

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mine does the same thing 0.6 0.7 wouldnt worry too much probably just a glitch. BTW I think I discovered another one. read my post "attitude monitor and cell phone glitch" If your slip read something like 35% when locked THEN I'D WORRY!!
 

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Mine "ticks" in and out of 0.0 and 0.6 when TC locked. I think it's just "noise" on the circuit and not a problem. Any slip that stayed up in TC lock would be a concern, but a flicker is no biggie.
 

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I was showing high slip when I was in 3 and driving around town.


Then when I was parked it would sometimes show N or 0.0%


What does this mean?
 

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put it to stock (level 0) and watch your slip numbers, all trannies slip to an extent. numbers get higher with increased throttle and change with shifting gears. Dont want to see any slip when locked. I guess N means none or neutral ?? not sure mine reads just like yours. wouldnt worry
 

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Ok....did more driving this is what I noticed.


Leaving the house 1st 2nd and 3rd only doing 15-40mph I was getting slip % from 5 to 60. (under normal driving conditions.....not mashing it)


Once I was on the highway....slip was 0.0% with .7% flash once doing about 80mph.


This is all in level 3.


Is this normal or not.....
 

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NoWake - the slip parameter includes the torque converter. So unless the torque converter is locked, you will have slip in the range you mention. You can display torque converter lock to prove this out. The harder you step on the throttle, the greater the slip (really the hydraulic coupling in the torque converter -- Mike L can explain better). The drive train is working as designed. Once the torque converter is locked, you should see no slip.





With regard to cruising the highway in 5th gear and torque converter locked and seeing 0.6% slip. Mine does the same. This bothered me initially. But it is almost periodic in nature when cruising at a constant speed. I don't believe anything is slipping while just cruising the highway. So I formed the following conclusion;


My guess is that the occasional 0.6% flash is just a numerical round-off error (LSB limitation on the sensors measuring the input/output shaft rotations). To detect slip, the circuitry must be measuring the transmission input shaft rotation and an output shaft rotation. In fourth gear, and with the torque converter locked, if there is no slip the difference between the input/output should be zero (0) (1:1 gear ratio). The problem is when cruising down the freeway; fifth gear is overdrive. So the difference between the input/output shaft rotations is not zero, but the Overdive Gear ratio of fifth gear (ratio of ~0.7). So now we must take into account the gear ratio. We no longer have a nice ratio of 1. The circuitry is just monitoring the counts of two sensors (input and output) and factoring in the gear ratio. Occassional, the numerical precision just catches up and a 0.6% slip is displayed (we only have a resolution of so many LSB's on the sensors). So as Idle_Chatter says, it is noise, and I believe it is noise induced by numercial precision of the circuitry.


Someone who has Over Drive lock-out could test the above theory. Just cruise down the highway in OD Lock-out (ie fourth gear). The rate of the 0.6% slips should decrease from the 5th gear rate.





Later,


AlanEdited by: OC_DMAX
 

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The "slip" numbers are only critical if you are showing any slippage when the torque converter is locked. It will "dance" off of 0.0% momentarily when locked, but that is just signal "noise" and is not a concern unless it displays slippage for more than a split-second. If you choose "torque lock" as an Attitude display option, you'll get a mostly blank screen with a little padlock icon when the TC is locked. If you choose the "gear" display option, you'll get the gear number and the little "TC lock" icon will pop up with the gear when the TC locks. The Attitude will display "0.0" or "N" when in neutral or not moving because there is no value being computed along that data stream in those conditions. Don't even worry about the slippage number when not in TC lock - the torque converter is "fluid coupled" and SHOULD be slipping when not locked! HOWEVER, if you read a slippage number when TC is locked, then there is a problem- with the TC, gear clutches or both!
 

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WOW guys thank you for the great information!


I did play more with the display....I displayed 'gear' and did notice the lock in 5th gear along with the lock on all the gear in tow mode. This would clear up why there was zero slip in 5th. I do think there was slippage in tow mode just for a second in 2nd and third. I will look closer next time I am on the road.


Thanks again for the great info!
 

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Tow haul locks in all except 1st. Regular only locks in 5th. TC will unlock in 5th below 50 mph and will delay locking up in 5th until transmission temperature gets up (sometimes it stays unlocked for 8 miles or so when I'm heading to work in cold conditions). The momentary slip you see in tow haul is probably actual slip as the TC locks and the gear clutches are coming up to pressure just after a shift. Don't get too fixated on the "information overload" next time you're on the road!
 

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Idle_Chatter said:
Don't get too fixated on the "information overload" next time you're on the road!

It is as if you have been in my passenger seat.



Thanks again!!
 

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Discussion Starter #12
thanks for the replys guys. i didn't think it was a problem but wanted another opinion mostly because the truck has 104000 on the OD and i think most of them were towing. was thinking about turning the attitude up to 5 and having some fun and using that extended warranty
 

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Discussion Starter #13
checked today and with OD off, it doesn't do it as much but still does it a little. with this many people having the same thing i don't think i will worry about it.


thanks again
 
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