Wierd shift

[HiHoeSilver]

I didn't know anyone ever ran cleaners through transmissions. I know many DIY'ers at home just drop the pan to change the filter and refill whatever fluid was lost with that. But there's still all that old fluid elsewhere in the trans and torque converter so dropping the pan only replaces about half.

I've seen shops use machines that basically refill the trans with new fluid as the old stuff is pumped out. Maybe this is what the call a "flush". Not sure if any run a cleaner during this process.

I pop off the hose that the fluid takes from the cooler back to the trans and have it drain into a large pan. With the engine running and trans in
"Neutral", I pour new fluid into the dipstick/fill tube (using a funnel) as the old fluid is pumped out. I continue this until the fluid coming out is the same color as the fluid going in, then continue for a quart or so to make sure. Then I change the filter, draining the trans pan into a clean pan and being careful to save as much as possible to re-use, then top off the fluid. I wouldn't consider this an aggressive "power flush". It's just a total fluid replacement.

I did mine similarly. I hooked up to the cooler line and pumped out the pan (4-5 qts). Then I dropped the pan. Changed filter, seal, gasket, and clean pan. Filled through dipstick, pumped, filled, pumped etc until clean. Ran it. Topped it off.

 

[Tatman48]

I didn't know anyone ever ran cleaners through transmissions. I know many DIY'ers at home just drop the pan to change the filter and refill whatever fluid was lost with that. But there's still all that old fluid elsewhere in the trans and torque converter so dropping the pan only replaces about half.

I've seen shops use machines that basically refill the trans with new fluid as the old stuff is pumped out. Maybe this is what the call a "flush". Not sure if any run a cleaner during this process.

I pop off the hose that the fluid takes from the cooler back to the trans and have it drain into a large pan. With the engine running and trans in
"Neutral", I pour new fluid into the dipstick/fill tube (using a funnel) as the old fluid is pumped out. I continue this until the fluid coming out is the same color as the fluid going in, then continue for a quart or so to make sure. Then I change the filter, draining the trans pan into a clean pan and being careful to save as much as possible to re-use, then top off the fluid. I wouldn't consider this an aggressive "power flush". It's just a total fluid replacement.

Gotcha... I just know an engine flush with go high mileage can be bad. Sometimes the sediment is the only thing keeping it from leaking and after a flush it leaks.... Thanks for info

 

[Tatman48]

Gotcha... I just know an engine flush with go high mileage can be bad. Sometimes the sediment is the only thing keeping it from leaking and after a flush it leaks.... Thanks for info

So i found out codes i have dont throw a check engine light. Says I need to change trans fluid pressure sensor. Anyone ever done that? If not which trans is in these beasts so i can look it up

 

[kbuskill]

So i found out codes i have dont throw a check engine light. Says I need to change trans fluid pressure sensor. Anyone ever done that? If not which trans is in these beasts so i can look it up

Your truck, because it is a Denali and has the 6.2L, came with the 6L80E 6 speed.

If it were a 5.3L 07-08 it would have the 4L80E 4 speed. The 5.3L didn't get the 6 speed until 09.

 

[Tatman48]

Cool, well

Your truck, because it is a Denali and has the 6.2L, came with the 6L80E 6 speed.

If it were a 5.3L 07-08 it would have the 4L80E 4 speed. The 5.3L didn't get the 6 speed until 09.

Cool, well apparently I need to change the trans fluid pressure sensors...

 

[Mrsteef]

Check motor mounts too. Mine would downshift really hard and it was the mounts were bad

 

[Tatman48]

Check motor mounts too. Mine would downshift really hard and it was the mounts were bad

Awrsome.... Has anyone did the pressure sensors themselves?