Hard Shifts at all times. Brown ATF <1K miles
08-06-2018, 01:48 PM
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Hard Shifts at all times. Brown ATF <1K miles I swapped an 03 5.3 envoy motor and trans into a colorado. Shifted just fine in the envoy. I definitely went too bis of a cam with the stock converter. SS2 Cam (228/230).
Upon startup and test drive, the trans seemed to shift hard from P/N to D/R and 1st into 2nd, it typically stalls if the truck isnt rolling when I put it in gear. Feels like the converter is slightly locked. Its also done this at a stop a few times.
So far i verified pressures in the tune were not too high, even dropped them a bit to see if it would help, it didnt.
any advice? Am i on the right track?
Update:
8 AUG - Shifts from P/N to any gear is so bad that it stalls the truck unless I give it some gas or unless the truck is rolling.
17 AUG - Swapped Throttle Body with known good to verify its not a TPS issue. No change
19 AUG - Ordered ATF Pressure gauge kit and Press control solonoid. awaiting delivery
26 AUG - Swapped MAF. No change
27 AUG - Tested cold pressure at idle 200 psi
27 AUG - Replaced PCS, verified no stuck check *****, replaced valvebody spacer/gasket. No change
3 SEP - Swapped out Vette servo for stock.
14 SEP - Swapped TCC Brake switch, verified TCC operation at cruising speed via HP tuners
15 SEP - verified fluid pressure again. See video below
16 SEP - Disabled Input Speed Sensor. This resolved pressure issue. No more slamming into Gear
7 OCT - Installed 2800 Stall, still seems to be an extra drag/load in gear
Upon startup and test drive, the trans seemed to shift hard from P/N to D/R and 1st into 2nd, it typically stalls if the truck isnt rolling when I put it in gear. Feels like the converter is slightly locked. Its also done this at a stop a few times.
So far i verified pressures in the tune were not too high, even dropped them a bit to see if it would help, it didnt.
any advice? Am i on the right track?
Update:
8 AUG - Shifts from P/N to any gear is so bad that it stalls the truck unless I give it some gas or unless the truck is rolling.
17 AUG - Swapped Throttle Body with known good to verify its not a TPS issue. No change
19 AUG - Ordered ATF Pressure gauge kit and Press control solonoid. awaiting delivery
26 AUG - Swapped MAF. No change
27 AUG - Tested cold pressure at idle 200 psi
27 AUG - Replaced PCS, verified no stuck check *****, replaced valvebody spacer/gasket. No change
3 SEP - Swapped out Vette servo for stock.
14 SEP - Swapped TCC Brake switch, verified TCC operation at cruising speed via HP tuners
15 SEP - verified fluid pressure again. See video below
16 SEP - Disabled Input Speed Sensor. This resolved pressure issue. No more slamming into Gear
7 OCT - Installed 2800 Stall, still seems to be an extra drag/load in gear
Last edited by Hawaiian_Built; 10-26-2018 at 10:06 PM.
08-20-2018, 07:51 AM
#3
TECH Junkie
put a pressure gauge on the trans. Eliminate guessing with the pressures and playing with them in the tune...use a gauge and report back readings for P/N/R/D/1 at idle and at about 1500 rpm brake stall
08-20-2018, 09:30 PM
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Thats a simple swap/test. I'll just pull the one off my other truck. Thank you
09-14-2018, 11:57 PM
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I swapped the MAF and it didn't help anything. Thanks for the tip though.
I put a gauge on and got it to idle (about 200 psi). tried to put it in drive and truck died. Tried to restart and battery was dead. Truck was in a spot difficult to jump start so I said screw it and just pulled the pan to swap out the PCS. I ended up pulling Valvebody and verifying no stuck *****.
Reinstalled everything and still having harsh P/N to D/R and 1 to 2. I think I might have messed up the gauge cause now its reading 0 psi. might have to buy another.
Reinstalled everything and still having harsh P/N to D/R and 1 to 2. I think I might have messed up the gauge cause now its reading 0 psi. might have to buy another.
09-15-2018, 07:46 PM
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I put the gauge back on and this was the results. When put in Drive, the rpm drops to about 600 and the accelerator pedal goes inactive.
Help
Help
Last edited by Hawaiian_Built; 09-15-2018 at 07:51 PM.
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09-16-2018, 05:09 PM
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I think I figured out part of the problem. Its a 2003 envoy 4l60e using a 2006 envoy tune. The input speed sensor needed to be disabled. I did this and now the 1 to 2 shift is rediculously slow. The P/N to R/D isnt as harsh anymore either but unfortunately, it still stumbles. I'll check the pressures again and report back.
10-26-2018, 08:19 PM
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Well, I still think theres an issue. I can start the truck and let it idle in P/N with the idle airflow minimum set around 8-10 grams per second, but in order for me to keep the truck running when shifting into D/R i have to set those gears to 14 g/s. Since disabling the input speed sensor in the tune, it no longer slams into gear anymore and idle fluid pressure stays around 85psi. I seems as though the trans is putting more load then necessary on the engine when placed in gear, if that even makes any sense.
Please help, I dont know transmissions very well
Please help, I dont know transmissions very well
10-26-2018, 09:06 PM
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TECH Junkie
Do you still have the stock converter? Sounds like the stock converter is just stalled too low for the large cam.
Also, you're going to need more idle airflow when in gear. Being in gear loads the engine more than in neutral. Have you had this properly tuned since the cam install?
Also, you're going to need more idle airflow when in gear. Being in gear loads the engine more than in neutral. Have you had this properly tuned since the cam install?
10-26-2018, 09:45 PM
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Do you still have the stock converter? Sounds like the stock converter is just stalled too low for the large cam.
Also, you're going to need more idle airflow when in gear. Being in gear loads the engine more than in neutral. Have you had this properly tuned since the cam install?
Also, you're going to need more idle airflow when in gear. Being in gear loads the engine more than in neutral. Have you had this properly tuned since the cam install?
I have been doing all the tuning. I am no expert, novice at best but I have tuned my other LS swapped turbo 5.3l so I feel alittle bit confortable. I;ve compared my P/N and In Gears idle air settings with other tunes and my P/N seems ok at 10g/s(will idle nicely set a 7-8). In Gear settings are really high at 14g/s which leave me with a higher idle then I want. Dropping below 14g/s causes stalling issues.