4L60e issues,...bout to take a 50cal and give er the whole 9 yards

[Hutchinson]

Thanks OleBlu, for confirming my logic (which surprised me that I was actually correct for once). My trans is built fair,...bout the only thing it doesn't have is the hardened input/output shafts.

Spec's are -
FLT machined performance pump.
Sonnax Smart Tech input housing (3-4 clutch drum) with koleen steels and additional frictions
Sonnax .490 boost valve
FLT sleeved input drum
FLT (billet 6061 aluminum) overrun piston
Sonnax SmartShell w/bearing kit
GM 5 pinion input carrier
GM 5 pinion reaction carrier
Bearing style reaction shaft
New reverse input drum
Alto wide 2-4 carbon lined band with reinforced anchor
B/W hi-energy 3-4 clutch pack
B/W double caged 29 element sprag
4L65 low roller clutch
Corvette Servo
Sonnax super hold 4th servo
B/W clutches
Updated aluminum accumulator pistons
FLT calibrated valve body w/ HD 2-3 shift valve modification
Set end play to FLT specs
Etc

So I should be safe to up the Force Motor table currents a little to see what happens. I'll try a 10% increase on the lower TPS%,...and blend cells between where I start/stop (thinking of adjusting the lower cells, up to ~50% TPS).

Unless you know I shouldn't do that. You guys have a lot more experience than I do.

[monte4ever]

The more you increase that table the lower the pressures are. I would leave that table alone. Try what I posted, if you don't like it change it back.

[Hutchinson]

My two cents is to definitely bump up the trans pressures that way it will firm up those shifts and I always fill my transmissions to the lower mark on the dipstick while the trans is hot.

EDIT: Under the "Shift Pressure Performance Table" try bumping the whole to 90psi.
Under the "Normal Table" change that to 90 psi from 240 to 640 then "Interpolate between Horizontal Lines" from 100 to 240. You should definitely feel a difference. If its too hard while cruising play with the Normal table. I got mine setup close to the above and it shifts nice and firm but not to hard however, I have a 3600 stall. I would also zero out the shift time table and everything on the Torque Management screen (tables).

Thanks Monte4ever, sounds good,....I'll open my tune and go over it here in a minute (I'm on my IPad right now, gotta switch over to my laptop). Would you do anything with the Force Motor table?
Do you have any ideas how we'd check clutch slip by reviewing input/output shaft, TCC slip as compared to engine rpm? I'd think we could somehow tell how much/if any clutch slip we have by looking into these numbers??? Thanks again man.

[monte4ever]

No, leave the Force Motor table alone. On the scanner you can add input-output shaft speed, shift time, TCC slip % etc....

[Hutchinson]

The more you increase that table the lower the pressures are. I would leave that table alone. Try what I posted, if you don't like it change it back.

Yes sir,...I'm dumb, I meant lower the Force Motor cells, to get a higher pressure,.... Yes Sir, will do per your other post.

[monte4ever]

Add time of latest shifts to your log file too. My times range from .1 sec (1st to 2nd) to 1.9 (3rd to 4th).

[Hutchinson]

Thanks Monte4ever,...Yes sir, I have time of latest shift, input shaft rpm, output shaft rpm, TCC slip, etc on the log I posted above,...do they not show up on the scan log? If not, I'll look into why it didn't come through.
My shift times range from .2 sec to the highest I've seen is 2.4sec (which is high from what I understand). I just switched over to the laptop and starting to look at the changes you stated,...I may have a question or two (as usual, you know me). Thanks again brotherman.

[Hutchinson]

As an example of what I trying to figure out/trying to confirm if my trans clutches are actually slipping,...I took a snapshot of the above attached log at 12.38.25

Trans in 3rd gear (which is 1 to 1 as far as input rpm to output rpm)
Engine RPM - 1837.0
Trans input Shaft RPM - 1195.5
Trans Output Shaft RPM - 1208.8
TCC Slip RPM - 637.0

If I add - Trans Input Shaft RPM + TCC Slip RPM = 1832.5,....which is close enough to the Engine RPM of 1837 (only 4.5 rpm off).
Yet, I'm not sure if its the right way to do it. Seems logical,...but, if that's the correct way to do it,... this would imply I really don't have any clutch slippage and its actually locked up fairly well. Or, is the TCC slip what we actually look at? If so, how can we tell if our clutches are working properly (and not slipping) during acceleration through each gear? I'd think the GM Engineers would have came up with a way for their techs to check unacceptable clutch slippage with a simple scan???? What y'all think??

[monte4ever]

Honesty, I'm trying to figure that out too.

[Hutchinson]

Some of those must be calculations the PCM does,... because there's no sensor tied to the Scanner results,.....Meaning,.....

I can see the Scanner showing -
Engine RPM - from engine
Trans output shaft - a calculation coming from the VSS (vehicle speed sensor)

But, those other two (TCC slip and Trans Input Shaft RPM),... I don't see where those two would get a physical sensor signal to provide there Scanner results,....so they must be calculated by the PCM. How these two are calculated is my mystery.

And, those two must purposely be there to serve some kind of purpose,....meaning GM Engineers/technicians must use it for something,.....in this case, I'm thinking "to check unacceptable clutch slip/out of spec",......but how it's done, I haven't a clue.

Somebody in our HPTuners world will know and provide the wisdom to the rest of us.

[Earwax]

According to GM/SI it should have an ISS (input shaft speed) it is in the front pump.
With engine RPM and ISS sensors calculating the converter/trans slip is easy.
If not equipped with an ISS,it monitors the difference between engine speed and transmission output speed.
According to your info,the trans is not slipping:
Trans Output Shaft RPM = 1208.8, - Trans input Shaft RPM = 1195.5 Equals 13 RPM.
Was the TCC unlocked during this test? Hopefully it was,as 637 RPM shows no TCC.
Check it the same way,but lock the TCC.The TCC slip should be very low.
Here is what I found in GM under a TCC code.Has it set any trans codes?
The powertrain control module (PCM) monitors the difference between engine speed and transmission output speed. In D3 drive range with the torque converter clutch (TCC) engaged, the engine speed should closely match the transmission output speed. In D4 drive range, with the TCC engaged, the TCC slip speed should be −20 to +50 RPM.
This info is from 06,the oldest still online through GM.
Hope this helps.

[monte4ever]

Good find.

[Hutchinson]

Thanks Earwax,....I think you hit the nail on the head man. GM introduced the ISS (Input Shaft Speed) sensor for 4L60e's in 2004,.....the ISS sensor mounts to the pump stator (housing) and measures the 3-4 clutch pack Input drum "shaft" rotation. The drum shaft has a reluctor around the shaft's base (right up next to the 3-4 clutch pack drum) which the ISS sensor uses to produce its signal to the PCM,....giving us an actual Input Shaft Speed.

Inlies the question,....,.....My truck is a 96,...with a 97 4L60e trans shell (same/same), and doesn't have an ISS on the pump stator or reluctor on the input drum shaft. Thus, I think you've answered the question,...the Trans Input Shaft RPM and TCC Slip RPM are simply PCM calculations derived from Engine RPM and Trans Output Shaft RPM (from VSS),...taking into account current transmission gear.

If someone has a 2004 or later model, then yeah man, those HPTuners Scanner results are based on an actual measurement/signal sent to the PCM and are an accurate rpm representation to be counted/used to detect individual clutch pack slip per gear.

Thus, since we (0411 upgraders/older vehicles) can't really use the Trans Input Shaft RPM or TCC Slip RPM scanner results for anything (because they're simply a PCM calculation,.. which doesn't reflect an actual measurement),.....it leaves us nothing to be able to check if our clutches are actually slipping inside the trans.

Check to see if this sounds bout right,.....I'm simply deducing here guys,...it's open for discussion (because I truly don't know) :

1. TCC Slip RPM = Engine RPM - Output Shaft Speed (factoring in existing gear),....As calculated by the PCM

Then, once the PCM has calculated TCC Slip RPM, it can then calculate Trans Input Shaft RPM,....

2. Trans Input Shaft RPM = Engine RPM - TCC Slip RPM,.....as calculated by the PCM

Realizing this is an ever-changing calculation (as engine RPM's constantly change),...could provide a reason why the numbers don't truly add up to zero-themselves out. Meaning, if you use the example I gave (5 posts up), we have a few RPM discrepancies between the calculated results (although it be low numbers like 8, 13rpm, etc).

Once the TCC locks the torque converter,....the TCC Slip RPM will drop to nearly no slip. But, none of this helps (us older vehicle guys/0411 swappers) with trying to determine if any of our clutch packs inside trans are actually slipping (more than spec'd) while running up through each gear. And, if, you indeed have clutches inside your trans slipping,...and then your TCC locks,...you may risk prematurely smoking your torque converter clutch inside your torque converter (because it's holding more power than it should be responsible for).

I'm thinking maybe,....the 0411 PCM has the Trans Input Shaft RPM and TCC Slip RPM PID's as simple calculations (for the earlier years 0411's),...but, yet, in readiness for when the ISS (Input Shaft Speed) sensor was to come along a year or two later???

Does any of this make sense? Please let us know if you know/see differently.

Man, we will all be 4L60e ex-squirts by the time we get through with this post. Lots of research/ people participating/ potential learning (at least for me anyway )

To answer your questions Earwax,...no Sir, my torque converter wasn't locked during the test/example results. Yes Sir, I can tell when my TCC locks because I can feel it engage and also see my Engine RPM's drop significantly. Admittedly, I haven't put the Scanner on it to see the TCC Slip RPM amount yet (when it locks),...but will do and report back. My worry is if I indeed have clutches inside my trans slipping, and the TCC locks the clutch, it may prematurely wear out the TC Clutch (because it's holding more than it should). What do you think about my logic being, since it's a calculation (on these pre 2004 trans/0411 PCM swaps) that we can't use the Trans Input Shaft RPM to see if we actually have clutch pack Slip? I'm probably all wrong here (as I usually am),....thus, the reason I ask these kinds of questions, so everyone can learn. Thanks for letting us know bout the ISS sensor, it should clears some things up.

[Earwax]

The way I see it written is that in 3rd gear with TCC locked. The engine RPM and Trans output speed should be almost the same. AS 3rd gear is 1:1. This assumes that both the TCC and the trans are not slipping. By doing the same test in 4th gear with the TCC locked you may see a negtive #. That is due to the ratio of 4th IIRC is .88? Also in 4th with the TCC locked would be a much greater load on the TCC clutch than 3rd gear.As I said earlier, I don`t think your trans is slipping. Usually there is a 100-600 RPM drop when the TCC is locked. This is from my poor memory of working for Chevy dealers for 30+ years.The later stuff is different as are different trans.Also GM never locked the TCC 100% (with PWM TCC). Which is great for customer driveability, but allows the clutch to slip.Of course you can change that with HP. I think the explanation below from GM explains it well.Concerning that the early 700`s lacked the ISS. When the TCC clutch slips, the converter turns a nice blue color.Usually when they came in for slipping complaints,I would verify it and then rebuild it with a new converter or put a SERTA Trans(GM rebuild) in it.Whichever was cheaper.

The powertrain control module (PCM) monitors the difference between engine speed and transmission output speed. In D3 drive range with the torque converter clutch (TCC) engaged, the engine speed should closely match the transmission output speed. In D4 drive range, with the TCC engaged, the TCC slip speed should be −20 to +50 RPM.

[Hutchinson]

Thanks Earwax, I appreciate your experience. And you've answered the questions I had,....and I thank you man.

I reckon I'll have to solely rely on the PCM to throw a trans slipping code (P1870) since the Trans Input Shaft RPM & TCC Slip RPM are simply PCM calculations on my 96 truck/0411 PCM swap. When I originally looked into this, I was trying to figure out how to verify myself (using the HPTuners scanner numbers), if I actually had any internal trans clutch slip,...which you answered, thanks man.

So far, it hasn't thrown any codes,...but, still feels like I'm not providing full motor power to rear end (like trans is slipping a bit),....up through the entire RPM range of each gear,....according to my butt-dyno .

Thus, I'll try the tune changes Monte4ever recommended and see how she acts. It's like the trans doesn't have the full holding power,...meaning, my truck speed doesn't feel right in respect to engine power/RPM,....kinda hard to explain really. But, admittedly, since it's a brand new trans, I haven't went past ~30% throttle yet. The actual "shift" feels good and crisp,.....maybe, it'll feel better when I put my foot into it more,....sounds like a good excuse to put my foot into it earlier than planned,..hehehe

I will say, when I hit ~53mph and the TCC locks (and engine rpm drops significantly) the trans feels good man,...real good. Just wish it felt a little more solid like that all the time (thus, the reason I started questioning if my trans internal clutches were slipping).

I'll keep plugging away at it, trying to figure out how to tighten up the internal clutches "holding feel" as I run up through the rpm range of each gear.

[Earwax]

If the fluid is staying clean and doesn`t smell burnt.It should be good to go.
Also make sure that the trans is not overheating.
if the trans or converter is slipping,it doesn`t take long to discolor / stink up the fluid.
It will darken and get a faint odor with normal use.
There are inline filters (look like a fuel filter,but they are magnetic)that splice into the cooler lines.
I think A/C Delco,Filtran Filters,Raybestos sell them.
Then you can run it and cut the filter open and look for yourself.
How much does the RPM drop when in 3rd with TCC applied? 4th?
Don`t make it shift so firm that it breaks parts. Yes it is possible to do.
Remember that if either the converter or trans fails, the fluid will transfer that contaminated fluid to everything.

[Jason B]

What a mess. And I didn't read the whole thread, I just remember this going on several months ago in the scanner forum.
FLT transmissions work with stock settings. I'd use an '02 silverado for all the pressure related stuff.

I probably said it before, I used to talk to two guys that built 4L60E's at FLT.
It will take some time for the clutches to feel consistent.
Hope you used a new converter.

Only tuning you need to do is speed related, especially with a new transmission. If something did happen you won't know if it was the programming or the trans. I lean on it being the programming.
Once you run it you can change the shift points and tcc lock up speed of needed. I wouldn't go further than that with the tuning til after a 100 miles or so.
Then if you get an annoying bump/slam, or soft shift just adjust the Base Shift Pressure vs torque vs Gear table.
It's that easy.

I started reading the thread and realized this might be the 4L60E powering the spaceship we're launching to Mars and stopped there. If it is then ignore me.

If it is actually powering a truck this thread and whole process has gone to the point that anyone is going to be confused. Theres a point where things make sense because they're normal practices, and the point where nothing makes sense because it's so over-thought that the basic function/goal no longer applies to the situation.

[Earwax]

Ok, you are ignored.
The OP asked a question and people are trying to answer it.
For every problem, there is more than 1 answer.
No one knows it all,some may think they do.
Not everyone on here is an XSPURT in tuning.

[Jason B]

Ok, you are ignored.
The OP asked a question and people are trying to answer it.
For every problem, there is more than 1 answer.
No one knows it all,some may think they do.
Not everyone on here is an XSPURT in tuning.

Yea 100 answers to the same question is worse than even asking. Especially when some answers are wrong, as in screwing with stuff that shouldn't be screwed with.
The square peg goes in the square hole...period. Well unless you do this and that to the round peg, and this and that to the triangular peg, and get a big hammer. Then you've instructed someone to ruin their shit.

[Earwax]

That is your opinion.
There are hundreds of people reading these posts.
Many of them are very experienced in the tuning of a transmission/engine.
I`m sure that if they saw someone giving incorrect advice,they would tell them so and correct their answer.
I have seen advice corrected many times.Usually, more than 1 tuner will reply.