Trans issue after 0411 PCM Swap

[davkenrem]

I have a 1997 Chevy K1500 Suburban, with a new L31-R Crate engine and rebuilt 4l60e. I did a 0411 PCM Swap to add efans and tune for the cam and headers. I used a 0411 PCM from a 2002 GMC Savana 2500 with the 5.7l and a 4l80. I did a segment swap from a Chevy Express 1500 with the 5.7l and a 4L60. I brought over the trans and trans diag from the 4L60. Used HP Tuners.

After the initial swap the trans shifted well other than the shift point came at a lower rpm than expected. I have not messed with those yet.

Been driving it for 3 weeks that way with no issues.

Today I made a 25 mile round trip to a friends house. About half way there the truck began to no longer shift back to first gear after coming to a stop. Seemed like it was still in OD. I would have to manually down shift into first and then take off then shift to third or OD and it would upshift fine. But at the next stop light same thing again. Got to my destination and checked trans fluid and it was full.

I let the truck set for about two hours then went to go home same thing again, about half way there no down shift at a stop.

I am very new to PCM Programming so I'm not sure if this is a PCM issue or a transmission Issue. I'm leaning toward PCM since the issue is intermittent.

Anyone have any ideas? Thanks in advance.

I can email tune if someone wants to look at it.

 

[TexasT]

If you move the lever down to 2nd and first, does the trans down shift?
You say it was rebuilt, but a "lesser" quality shop might not have replaced the shift solenoids and electrical stuff on the vb and when it heats up it causes probs.
What are you doing to get it to down shift, then when you go again does it shift back up through the gears?

 

[davkenrem]

I think I found an issue, Ran a log file today and trans temp went as high as 249 degrees. Gonna get it to the shop this week.

 

[Htoo]

I have a 1997 Chevy K1500 Suburban, with a new L31-R Crate engine and rebuilt 4l60e. I did a 0411 PCM Swap to add efans and tune for the cam and headers. I used a 0411 PCM from a 2002 GMC Savana 2500 with the 5.7l and a 4l80. I did a segment swap from a Chevy Express 1500 with the 5.7l and a 4L60. I brought over the trans and trans diag from the 4L60. Used HP Tuners.

After the initial swap the trans shifted well other than the shift point came at a lower rpm than expected. I have not messed with those yet.

Been driving it for 3 weeks that way with no issues.

Today I made a 25 mile round trip to a friends house. About half way there the truck began to no longer shift back to first gear after coming to a stop. Seemed like it was still in OD. I would have to manually down shift into first and then take off then shift to third or OD and it would upshift fine. But at the next stop light same thing again. Got to my destination and checked trans fluid and it was full.

I let the truck set for about two hours then went to go home same thing again, about half way there no down shift at a stop.

I am very new to PCM Programming so I'm not sure if this is a PCM issue or a transmission Issue. I'm leaning toward PCM since the issue is intermittent.

Anyone have any ideas? Thanks in advance.

I can email tune if someone wants to look at it.

 

[Htoo]

I’d like to see how to tune the PCM. Please send me to this gmail account.
[email protected]