Rough shift on 4L60E

[matuva]

Good day all,

we are having trouble with a 4L60E on a 1999 Silverado 1500 (gasser with the 5.3l Vortec).

Shifting from 1 to 2 is very rough, and usually you have to reach 4 000 rpms before it bangs and goes to 2nd.

Other speeds are still rough, though a bit softer.

All internal solenoids and harness are new

Sometimes I can hear something squealing. I have very few experience with AutoEnginuity for diagnosing trans problems, though,
this is what I can measure :




Once you reach the speed of 80 kph (50 mph), the TCC value goes down in green, around 16~20. What shows this "TCC duty cycle"

I'm thinking the converter is shot, what do you think?

 

[tanman_2006]

Sounds like what my 4l60 did, clutches burned up or you snapped a hard part in the tranny. If you have had valve body off its worth checking to see if it is still together correctly.

 

[THEFERMANATOR]

I would start with the throttle position sensor if it was me. They will routinely fail in a manner that makes them read higher voltage than they should, but they won't normally code when this type of failure happens. When it does it will stretch the shifts out, and yo uget hard shifts. Also being a 5.3L, clean the MAF with some MAF cleaner or electrical cleaner(do NOT use carb cleaner as it will destroy it). MOSt shifting issues with the newer trucks are releated back to the MAF sensor being dirty or oily from a oiled type of air filter.

 

[matuva]

OK, the owner decided to go to the MAF and TPS route. Ordered the 2 and will see what's going on.
Anything special to do to install the TPS?

 

[THEFERMANATOR]

OK, the owner decided to go to the MAF and TPS route. Ordered the 2 and will see what's going on.
Anything special to do to install the TPS?

You should have scanned it first to see what they are doing. I doubt both are bad at the same time, and the MAF RARELY fails(it just gets dirty and needs cleaned). You need to reset the adapts in the ECM when you replace the TPS. This is done via a scan tool. Also make CERTAIN it isn't throwing a P1870 code.

 

[matuva]

You should have scanned it first to see what they are doing. I doubt both are bad at the same time, and the MAF RARELY fails(it just gets dirty and needs cleaned). You need to reset the adapts in the ECM when you replace the TPS. This is done via a scan tool. Also make CERTAIN it isn't throwing a P1870 code.

I scanned for codes before and didn't find any. I was too hunting for this P1870 code, but there was none.

Do you know if Auto Enginuity scan tool can reset the PCM?

 

[THEFERMANATOR]

Not sure if it can reset it or not. You needed to log your TPS percentage and voltage's to see if they were linear, within range(should be around .5-.8 at idle I think, and around 4.5 at WOT), and smooth. As for the MAF, you REALLY need to keep an eye on it as the later trucks shift via airflow for them ost part using the EC3 shift strategy.

 

[Ed HD]

Also, unless you ordered an AC Delco or Delphi MAF sensor, send it back. The aftermarket ones are junk.