Automatic transmission shifting problem

[Dave1027]

Just put in gear and roll through the gears slowly. Make sure your dsc is off otherwise the car will sense loss of traction and deploy the brakes. Ask me how I know.

I kept my foot on the brake while cycling through the gears. Didn't do anything with DSC.

[TigerTater]

I kept my foot on the brake while cycling through the gears. Didn't do anything with DSC.

Yes but I wanted the trans to run through gears not just select them, so that the oil actually cycled through the cooler as well. Helps increase the amount of ATF that actually gets cycled out/through the system.

[Dave1027]

I'm running Valvoline Dexron 6 with the GM 390 steptronic. Works perfect.

Revisiting this because I was getting some odd transmission behavior with the cold weather. Did some researching which led me to believe the original fluid for this transmission was dex 3 compatible which is a thicker fluid than dex 6. Decided to try some dex 3 and notice the tranny does seem to have more "traction". It shifts at slightly lower RPMs. Seems to move better in 1st gear. The down side could be that I have lost a slight amount of mpg. Still researching.

[Pip]

Revisiting this because I was getting some odd transmission behavior with the cold weather. Did some researching which led me to believe the original fluid for this transmission was dex 3 compatible which is a thicker fluid than dex 6. Decided to try some dex 3 and notice the tranny does seem to have more "traction". It shifts at slightly lower RPMs. Seems to move better in 1st gear. The down side could be that I have lost a slight amount of mpg. Still researching.

Can you elaborate on cold? Was it not wanting to move until warm?

[Dave1027]

Hey Sean,

Yes. Slow moving till I got a half block down the street then it began to get full power to the wheels gradually. I had full power by the time I got to the end of the block.

[Pip]

Hey Sean,

Yes. Slow moving till I got a half block down the street then it began to get full power to the wheels gradually. I had full power by the time I got to the end of the block.

I always wondered if that was the fluid. I had a similar thing happen once but it doesn't really get that cold in Sac especially when storing the car in the garage. Hope the new owner doesn't experience this and get taken by a shop.

[WOLFN8TR]

Lately it's been pretty cold here in the mornings, 27-37 degrees. My car was stored in the garage up until I bought the ///M. Usually I start it and let it warm up a few minutes and drive off. I started noticing the car felt really sluggish on cold mornings. I thought it was the sign of some tranny problems. This morning my ZHP was outside in the driveway and it was 37 degrees. I started the car and let it warm up for approx 10 minutes. Drove off with NO problems. I never had any issues until I changed the oil, I used Redline. Thicker Redline oil vs oem?

[Dave1027]

On paper, Redline D4 sounds like a great substitute for oem. The viscosity numbers are close with Redline D4 being a little thinner. Being a synthetic, D4 does not shear down like the oem Texaco ETL.

[Pip]

On paper, Redline D4 sounds like a great substitute for oem. The viscosity numbers are close with Redline D4 being a little thinner. Being a synthetic, D4 does not shear down like the oem Texaco ETL.

For sure but I had some issues that no zhp owners but me have reported.

I had some slipping between 1-2 with OEM, worse with D4, and about same as OEM with Dex 6 but that had the cold start problem.

[Dave1027]

I think I might have the problem resolved.

I replaced the TCC solenoid in the valve body. Did that along with a new filter and 6 quarts of Mobil 1 full synthetic ATF. $17 for the solenoid, $30 for the filter and $60 for the fluid. Total $107 and it feels almost like a new tranny.

I got the information from this thread.

I have only tested out two mornings so far and this morning was a balmy 39F. Not super cold but it seems like the throttle is more responsive. Only have to press the gas pedal a small amount gets the car moving.