4L60e will not upshift at WOT
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Joined: Aug 2010
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From: Ann Arbor, MI
As I answered to ninetyeightbird above, and as mentioned in the other posts today, a stock tune with a high stall converter will have this problem, largely because a higher-than-stock stall converter will have a bit more slippage.
My guess is that your converter recently started to slip even more, with the result that your previous tune no longer shifted at WOT. I don't know enough about converters to say whether/how they can slip more; perhaps someone else can state whether that is possible. (Since a converter can fail, I assume there must a state between perfect and failed.)
Well everything else works with this stock PCM. Yes I have an LS6 crate engine, headers, converter, no cats, air and egr and yes my SES light is on but it starts right up, runs, drives, and shifts fine except of course the WOT upshift. I also already spoke with a reputable tuner... Geoff Skorupa from Next Level Performance(who also installed my engine) he put a scanner on it and we went for a drive and also narrowed it down to the pcm not commanding the shift...I haven't spoken to him since though.
First, I'm honestly sorry that you are still having the same problem. I would have been happy to send you the $5 if it had been the PCM.
As I answered to ninetyeightbird above, and as mentioned in the other posts today, a stock tune with a high stall converter will have this problem, largely because a higher-than-stock stall converter will have a bit more slippage.
My guess is that your converter recently started to slip even more, with the result that your previous tune no longer shifted at WOT. I don't know enough about converters to say whether/how they can slip more; perhaps someone else can state whether that is possible. (Since a converter can fail, I assume there must a state between perfect and failed.)
As I answered to ninetyeightbird above, and as mentioned in the other posts today, a stock tune with a high stall converter will have this problem, largely because a higher-than-stock stall converter will have a bit more slippage.
My guess is that your converter recently started to slip even more, with the result that your previous tune no longer shifted at WOT. I don't know enough about converters to say whether/how they can slip more; perhaps someone else can state whether that is possible. (Since a converter can fail, I assume there must a state between perfect and failed.)
This is what I'm being told
Transmission builder"I'm 100% positive it's not the trans
Tuner"I'm 100% positive it's not the tune"
What's a different tuner going to do that Keith at PCMforless can't do? Hes done thousands of tunes and I think he pretty much knows what he's doing but if there's something I can tell him let me know. I just paid him for a retune and to fix this prohlem and before I pay someone else I'm sending it back to him.
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Joined: Aug 2010
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From: Ann Arbor, MI
I would suggest asking him to reduce the WOT upshift speeds by a few mph.
If you are comfortable with it, I would also increase the redline by 100 or 200 rpm.
That will likely take care of it for you. If your tuner is using HP Tuners, kindly ask him to send you the tune file too. In the unlikely case the problem still isn't fixed, you could then post the tune file for more feedback.
If you are comfortable with it, I would also increase the redline by 100 or 200 rpm.
That will likely take care of it for you. If your tuner is using HP Tuners, kindly ask him to send you the tune file too. In the unlikely case the problem still isn't fixed, you could then post the tune file for more feedback.
I would suggest asking him to reduce the WOT upshift speeds by a few mph.
If you are comfortable with it, I would also increase the redline by 100 or 200 rpm.
That will likely take care of it for you. If your tuner is using HP Tuners, kindly ask him to send you the tune file too. In the unlikely case the problem still isn't fixed, you could then post the tune file for more feedback.
If you are comfortable with it, I would also increase the redline by 100 or 200 rpm.
That will likely take care of it for you. If your tuner is using HP Tuners, kindly ask him to send you the tune file too. In the unlikely case the problem still isn't fixed, you could then post the tune file for more feedback.
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
The PCM has very little information about the trans, only what gear the selector is in, the engine rpm, the output speed from the VSS and the trans temperature.
I don't see how a check ball could change the upshift command, but I'm no trans expert. Replacing the separator plate and all the check ***** is not a big deal and does not require removing the trans. I just hope you solve this soon for your sake.
I don't see how a check ball could change the upshift command, but I'm no trans expert. Replacing the separator plate and all the check ***** is not a big deal and does not require removing the trans. I just hope you solve this soon for your sake.
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Verdad Gallardo This is what I need to confirm, if an internal trans problem can cause the computer not to give the upshift command. The builder is telling me if the PCM isn't getting the command it's a PCM or tune problem as is another tech with a scanner. Others are telling me even though the computer isn't getting the command it can still be the seperator plate and check ball. Before I take it back to the trans shop and try and convince him to drop the pan can anyone confirm this?
What is your opinion on this problem possibly being the separator plate and or check ball in the valve body?
Spoke with my transmission builder again today I told him I tried another PCM he said there's no way a loose check ball or enlarged separator plate hole will cause the computer not to command the wot upshift and he's still 100% positive it's not the trans.
Last edited by Black98T/A; Apr 2, 2012 at 07:31 PM.
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Joined: Aug 2010
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From: Ann Arbor, MI
I (and perhaps others) mentioned several times in this thread that it could be the VSS sensor. I don't know how the VSS sensor can partially-fail, but I have read other posts here about people solving their no-WOT-upshift problem with a new VSS.
When the PCM detects WOT operation, it uses a different algorithm to determine when to upshift. In particular BOTH the tuned (programmed) speed and RPM must be reached before the upshift occurs. If the speed is too low for any reason (slipping torque converter, defective VSS), then the upshift never occurs. That is why we kept telling you to tune for a lower upshift speed.
A new VSS is only $20 from your local parts store. Give it a try and let us know. Easy to put in too from underneath on the passenger side. Unsnap the connector, one bolt (10mm?) holds the sensor, lube the new one's o-ring with a little trans fluid and install it.
I tried a new VSS and even though my trans builder roriginally told me that sensor works or it doesn't I bought one anyway...no luck speedo is still 10-15 off and still no wot shift. 
My speedometer is off with both a tuned and stock pcm..with a correct speedometer I will probably get the shift at wot but how can I fix it??
My speedometer is off with both a tuned and stock pcm..with a correct speedometer I will probably get the shift at wot but how can I fix it??
Well I'm taking the car to another shop tomorrow that does speedometer repair I don't know what else to do at this point I've tried 3 different tunes, 2 pcm's 2 different sets of tires, a vehicle speed sensor and the speedo is still off and the trans is not shifting at WOT
Moderator
Joined: Aug 2010
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From: Ann Arbor, MI
Well I'm taking the car to another shop tomorrow that does speedometer repair I don't know what else to do at this point I've tried 3 different tunes, 2 pcm's 2 different sets of tires, a vehicle speed sensor and the speedo is still off and the trans is not shifting at WOT
This is what I don't get
Oct 08-I bought car basically stock all it had done to it was a lid and Flowmaster. 3.23 gears and 315/17 tires. Speedo was correct and car shifted at WOT.
Jan 10-I have PCM tuned for ls6 crate. I list car has 3.23 gears on order sheet. Speedo and WOT upshifts are correct.
Nov 10-295/18 go on in rear I notice no difference in speedo wot shift occurs
May 11-I notice trans is not shifting at WOT I don't notice speedo being off also. Transmission starts to slip and car is parked until rebuilt trans feb 12
So something caused the speedo to be off right around may of last year which caused my no upshift at wot which possibly caused my trans to go. I just remember being on the highway and passing someone and the trans not shifting and smelling something burnt and feeling the trans slip right after.
Oct 08-I bought car basically stock all it had done to it was a lid and Flowmaster. 3.23 gears and 315/17 tires. Speedo was correct and car shifted at WOT.
Jan 10-I have PCM tuned for ls6 crate. I list car has 3.23 gears on order sheet. Speedo and WOT upshifts are correct.
Nov 10-295/18 go on in rear I notice no difference in speedo wot shift occurs
May 11-I notice trans is not shifting at WOT I don't notice speedo being off also. Transmission starts to slip and car is parked until rebuilt trans feb 12
So something caused the speedo to be off right around may of last year which caused my no upshift at wot which possibly caused my trans to go. I just remember being on the highway and passing someone and the trans not shifting and smelling something burnt and feeling the trans slip right after.
Last edited by Black98T/A; Apr 4, 2012 at 06:40 PM.
Ok just an update...I took the car to a tuner today he hooked his laptop up and we went for a ride, I also had my iphone speedo app on. The first thing I noticed about the car being off last month was the tach, I remember being on the highway cruising and seeing almost 3k rpm and feeling that can't be right, I later noticed my speedo was off when cars started passing me, my iphone app confirmed speedo was off and any wot shifting I've been doing I've been letting off as to not blow the motor right before 7k rpm except 7k rpm isn't 7k rpm it's about 6k rpm! The tuner adjusted the tables to correct the speedo like he gave it a higher gear which corrected the speedo but not the tach and lowered the shift points a little, We did a couple of wot shifts from a dig and a roll, I let the tach go to 7k rpm and yes the wot shifts occur so basically spedo is correct now, the tach is still off and shift points are a little lower then optimal for performance but it shifts. I'm going to try a used cluster and if that corrects the tach, tune the shift points back up and adjust the speedo for the correct gears...if the cluster doesn't fix the tach then I don't know in the wiring somewhere??
