I've seen a few trans experts in here...
2008 Tahoe
1-2 shifs hard at part throttle. Little throttle and full throttle good. Other shifts feel good. MAYBE 2-3 slightly soft part throttle, but not noticable.
Symptoms improve as temps increase. Cold is worst. Hot is very good.
Replaced 1-2 accumulator. No change.
Replaced valve body, no change.
While in there, replaced TCC valve with updated sonnax parts.
Replaced 2-4 servo with the infamous "Corvette" apply area. 1-2 worse, 2-3 ok. Yeah, getting to be parts cannon time.
Here's the odd part: if I reset TAP data, it shifts perfectly for a few days, then as TAPS data builds, the symptoms return.
Getting even more odd: TAP data on the 1-2, which shifts hard, show boosted pressure. The 2-3 shift that's maybe slightly soft, show pressure reduced. It's like a self-inflicted problem.
To my uneducated self, the perfect shifting after data reset means hard parts and hydraulics are likely ok. I'm curious if this could be an EPC problem?
Please advise!
2008 Tahoe
1-2 shifs hard at part throttle. Little throttle and full throttle good. Other shifts feel good. MAYBE 2-3 slightly soft part throttle, but not noticable.
Symptoms improve as temps increase. Cold is worst. Hot is very good.
Replaced 1-2 accumulator. No change.
Replaced valve body, no change.
While in there, replaced TCC valve with updated sonnax parts.
Replaced 2-4 servo with the infamous "Corvette" apply area. 1-2 worse, 2-3 ok. Yeah, getting to be parts cannon time.
Here's the odd part: if I reset TAP data, it shifts perfectly for a few days, then as TAPS data builds, the symptoms return.
Getting even more odd: TAP data on the 1-2, which shifts hard, show boosted pressure. The 2-3 shift that's maybe slightly soft, show pressure reduced. It's like a self-inflicted problem.
To my uneducated self, the perfect shifting after data reset means hard parts and hydraulics are likely ok. I'm curious if this could be an EPC problem?
Please advise!
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