According to the GM manual a 4L80 requires 7.3 litres of fluid for just a pan change and and 12.8 litres after overhaul.
I removed 5l from my pan, filled it with 7.3l, pumped a further 6.5l out of it to flush the TC and then added 5l and on level ground the dipstick has oil way beyond the marks - right up at the second (from bottom) kink in the stick. Fluid still cold and cooler empty (as thermostat now fitted). No leaks or oil loss through the breather (if there is one). It drives fine. Ran it through all the gears while stationary as recommended and drove in D all the way to 4thOD.
So, 11.5l removed, 12.3l added and the stick is showing it to be overfilled.
I didn't get the chance to check the stick on level ground before I started - only on a steepish sloping driveway, truck pointing nose down. It was u to the first kink. After draining the 5l and adding 7.3l (before TC flushing) it was up to the space between ENGINE and IDLING on the stick.
In the same orientation the current level is up to the start of the script stamped into the stick (but to the second kink on level ground).
I have in it 0.5l more than before (it ran OK before) and have underfilled it relative to GM's figures. GM figures ie, 7.3l into the pan.
Were there different size pans? Confused that mine only had 5l in it but adding the recommended 7.3l is looking like a massive overfill on the stick despite me still holding back 1.5l (6.5l removed from TC, only 5l added to replace that). The cooler will still be empty (but it doesn't hold that much).
Should I remove some or run as is (as I haven't achieved GM's recommended fill quantity so underfilled from that perspective)?
I removed 5l from my pan, filled it with 7.3l, pumped a further 6.5l out of it to flush the TC and then added 5l and on level ground the dipstick has oil way beyond the marks - right up at the second (from bottom) kink in the stick. Fluid still cold and cooler empty (as thermostat now fitted). No leaks or oil loss through the breather (if there is one). It drives fine. Ran it through all the gears while stationary as recommended and drove in D all the way to 4thOD.
So, 11.5l removed, 12.3l added and the stick is showing it to be overfilled.
I didn't get the chance to check the stick on level ground before I started - only on a steepish sloping driveway, truck pointing nose down. It was u to the first kink. After draining the 5l and adding 7.3l (before TC flushing) it was up to the space between ENGINE and IDLING on the stick.
In the same orientation the current level is up to the start of the script stamped into the stick (but to the second kink on level ground).
I have in it 0.5l more than before (it ran OK before) and have underfilled it relative to GM's figures. GM figures ie, 7.3l into the pan.
Were there different size pans? Confused that mine only had 5l in it but adding the recommended 7.3l is looking like a massive overfill on the stick despite me still holding back 1.5l (6.5l removed from TC, only 5l added to replace that). The cooler will still be empty (but it doesn't hold that much).
Should I remove some or run as is (as I haven't achieved GM's recommended fill quantity so underfilled from that perspective)?