4l60e 65e 70e technical thread, cooler install codes, diagrams more!
05-14-2009, 02:15 AM
#31
Speed Density (MAF-less) tune... Here's some hints if you're running a SD (MAF-less) tune and the trans seem to shift harsh:
Disable P0101, P0102, P0103 in the following tables:
- Transmission DTC Fault Max Pressure Enablers
- Transmission DTC Fault Pressure Modifiers
Also disable P0101, P0102, P0103 in this table:
- Transmission Failsafe Enablers
Also check this table for/disable P0101, P0102, P0103:
- Transmission DTC Fault Processing Enablers
(that table probably won't contain those 3, but check it anyway)
Also do this (very important):
When driving monitor/log DYNCYLAIR, TRQENG, TFMPRS...
The PCM computes DYNCYLAIR from the VE table for various purposes:
- to compute/lookup fueling/fuelmass,
- to compute/lookup spark timing,
- to compute/lookup TRQENG;
TRQENG is used to compute/lookup the PCS current (or duty cycle) to drive the PCS with... in the hydrualic schematics the PCS produces Torque Signal pressure which drives the Boost Valve which assists the Isolator spring in driving the Pressure Regulator valve to control line pressure.
So, if the VE table is low, then DYNCYLAIR will be low, which causes TRQENG to be low, which causes Torque Signal pressure to be low, which causes line pressure to be low, which causes slippage which kills the transmission and the fluid.
When you view a log of TRQENG and TFMPRS, look at the shift pressure tables in the transmission calibration and see which cells TRQENG is looking up... at WOT these should be saying 80+ psi for TFMPRS.
So if you're running/tuning in SD be careful that the VE table is not going low by mistake (it will make your transmission slip, and it will make your AFR lean which will increase CC temps, cause knock, damage motor).
By JOECAR on LS1TECH
05-14-2009, 12:07 PM
#35
6-Allowing a transmission to set either in or out of the car for extended periods (months/years) can result in failure.
Yes actually it can. As the transmission sets for long periods of time fluid will slowly run down and away from the clutches and hard parts. The seals can even dry rot similar to the way tires do and more in damp climates moisture can enter and cause rust on hard parts and even under the lining of the friction materials and cause them to separate. I have heard the “It worked great when I took it out 2 years ago story” and its likely a true statement only to hear later that someone put it back in and it died in days or weeks or slipped or other wise acted up from sticky valves. My suggestion for storing a transmission for any length of time is to plug all the holes and fill till the fluid begins coming out of the overflow tube. Then cap this to as that will insure all parts are submerged in fluid. You will just need to drain before restarting after storage. This may help avoid some post I see with transmission complaints after taking a car out of storage that has been setting all winter.
DAMN. My 4l80e could be rotting!
Yes actually it can. As the transmission sets for long periods of time fluid will slowly run down and away from the clutches and hard parts. The seals can even dry rot similar to the way tires do and more in damp climates moisture can enter and cause rust on hard parts and even under the lining of the friction materials and cause them to separate. I have heard the “It worked great when I took it out 2 years ago story” and its likely a true statement only to hear later that someone put it back in and it died in days or weeks or slipped or other wise acted up from sticky valves. My suggestion for storing a transmission for any length of time is to plug all the holes and fill till the fluid begins coming out of the overflow tube. Then cap this to as that will insure all parts are submerged in fluid. You will just need to drain before restarting after storage. This may help avoid some post I see with transmission complaints after taking a car out of storage that has been setting all winter.
DAMN. My 4l80e could be rotting!
