Soft shifting 60e

[Gambles]

Truck just got ls swapped, stock 5.3 with a fresh 60e dude drove it 30-45 minutes no issues, test drives it again 10 minutes while I’m driving to pick it up, shreds 3-4 clutches at like 48% throttle.. trans was built less then 5000 miles ago with a 5.0 on It, wonderful stiff shifts. so I have it pulled and gone through by my tranny guy, everything looks brand new except the 3-4 clutches, replaced them and opened the valve body up, I believe he said. Which should have further stiffened my shift points. Guy puts tranny back in does some tuning, now it’s a loose butthole all the way up just smooth as butter and slipping all the way, now I am driving home with no phone at this point so it’s 3 miles to home or 15 back to the shop, so I go home, check fluid still clear and red doesn’t smell burnt, only caught 2 stop lights and a stop sign, didn’t slip at the stop sign or the first light just lightly cruised up, but at the last light it idled down to like 450 rpm threw a knock sensor code, and slipped all the way up to third, it didn’t seem to slip 4th but then It’s like 6-7 houses so I just coasted it back to my house and up in the drive way, where it slipped first trying to drive slope, did not sound rough anything. Could it be something going on with his tune, or what’s best way to check my bases? Tranny guy says it’s the tuner, tuner says it’s the tranny guy basically.

 

[df2x4]

I see an 80E swap in your future...

The 60Es are garbage, I killed two behind a stock 4.3L V6. That being said, I'd figure out if your tuner altered the torque management at all. If he did, have him put that back to factory settings. Removing torque management definitely kills them quicker.

 

[Gambles]

Yeah, I was hoping to not go that route from what I hear it’ll slow ya down some because ratio and weight. But seems to be the only option at this point if I can’t figure out what’s going on, damn shame it’s slipping with 6 miles on it..

 

[df2x4]

You'll definitely lose a little bit of power going to a 4L80E but it's not what a lot of people hype it up to be. My 80E swapped V6 truck still gets going just fine. Lots of folks don't realize that the 80E was a factory offering in the 4.3L V6 2500 Express vans.

And believe me I hear you on the low mileage death. My 60E rebuild/beef up cost me $2700 and lasted less than 10K miles. I didn't want to do that again so I went the 80E route.