Hello! I am brand new here and I apologize in advance for the lengthy message, but I am in need of some assistance!
So my father in law had a 2013 GMC Sierra 2500HD with a 6.0 and a 6l90. He bought it used at 45k and has done no transmission maintenance since. It had just hit 180k and the transmission went. Apparently it was shuttering on the highway one day and the next it barely moved. He told me that it wasn't worth paying the dealer the $8,000 they quoted him to have it replaced, and he told me that it was mine if I wanted it.
I figured that the torque convertor went, plugged the filter, and starved the unit. I ordered a new TC and a rebuild kit from GlobalTransmissionParts. I did new clutches, seals, steels, but no new "hard" parts. I got the bellhousing and pump machined at a local shop (and I got a new .020 thick washer for the back of the stator to make up for the endplay). He had just bought a new radiator 3 months ago so I just cleaned it and the aux. cooler as best I could, with the intention of bringing it down to a local shop for a hot flush when I was done. I did get brand new lines though to fix the rust.
The rebuild went better than I expected, and the unit wasn't as complicated as anticipated (or so I thought). I put it back in on Tuesday, filled and test drove, but it wouldn't shift into 4th. 1, 2, and 3 are fine but it just revs when it tries to shift up into 4th, and then sort of slams back down into 3rd. Reverse was also a little sluggish. I saw online that the 3-5-r drum is tough to get in so I assumed I just didn't have it fully seated into the 4-5-6 drum. I pulled it back out on Wednesday (big fan of doing it in the driveway on jackstands) and tore it all back apart. It all looked completely normal and I couldn't tell anywhere that I went wrong, but there was a little bit of metal in the pan. I put it all back together and after some research did the air checks. 3-5-R engaged, 1-2-3-4 engaged, 4-5-6 engaged, 2-6 engaged, and L-R engaged and all held pressure as expected (going off the Nick's Transmission video I was watching). So I figured I had just put it together wrong the first time. I put the unit back in the truck last night and went for a test drive this morning, and no luck. Still no shift up into 4th. Again, reverse was a little sluggish at times, I put it into reverse and it wouldn't move without significant throttle input, but sometimes it would act normally.
So at this point I am a little lost, and somewhat disheartened. Am I putting the unit together wrong? I am like 99% sure that everything is fully down and seated. When fully assembled the top of the 3-5-R drum is almost flush with the opening where the pan would be and the filter would go through into the pump. Or is it a control problem? I did the Sonnax zip kit for the valve body and everything felt pretty normal. All of the rods (not sure what they're called) would spring back with the retainers in. I also did the Sonnax upgrades in the pump. I reused the TECHM. Could that be my problem? I borrowed a buddy’s scan tool and it showed that it was commanding into 4th, but it didn’t show me if the solenoid was actually engaging.
Again, sorry for the super long, and somewhat all over the place, message. But I am sort of at a loss and not sure where to go from here. Any help would be greatly appreciated, even if just a direction to go!
So my father in law had a 2013 GMC Sierra 2500HD with a 6.0 and a 6l90. He bought it used at 45k and has done no transmission maintenance since. It had just hit 180k and the transmission went. Apparently it was shuttering on the highway one day and the next it barely moved. He told me that it wasn't worth paying the dealer the $8,000 they quoted him to have it replaced, and he told me that it was mine if I wanted it.
I figured that the torque convertor went, plugged the filter, and starved the unit. I ordered a new TC and a rebuild kit from GlobalTransmissionParts. I did new clutches, seals, steels, but no new "hard" parts. I got the bellhousing and pump machined at a local shop (and I got a new .020 thick washer for the back of the stator to make up for the endplay). He had just bought a new radiator 3 months ago so I just cleaned it and the aux. cooler as best I could, with the intention of bringing it down to a local shop for a hot flush when I was done. I did get brand new lines though to fix the rust.
The rebuild went better than I expected, and the unit wasn't as complicated as anticipated (or so I thought). I put it back in on Tuesday, filled and test drove, but it wouldn't shift into 4th. 1, 2, and 3 are fine but it just revs when it tries to shift up into 4th, and then sort of slams back down into 3rd. Reverse was also a little sluggish. I saw online that the 3-5-r drum is tough to get in so I assumed I just didn't have it fully seated into the 4-5-6 drum. I pulled it back out on Wednesday (big fan of doing it in the driveway on jackstands) and tore it all back apart. It all looked completely normal and I couldn't tell anywhere that I went wrong, but there was a little bit of metal in the pan. I put it all back together and after some research did the air checks. 3-5-R engaged, 1-2-3-4 engaged, 4-5-6 engaged, 2-6 engaged, and L-R engaged and all held pressure as expected (going off the Nick's Transmission video I was watching). So I figured I had just put it together wrong the first time. I put the unit back in the truck last night and went for a test drive this morning, and no luck. Still no shift up into 4th. Again, reverse was a little sluggish at times, I put it into reverse and it wouldn't move without significant throttle input, but sometimes it would act normally.
So at this point I am a little lost, and somewhat disheartened. Am I putting the unit together wrong? I am like 99% sure that everything is fully down and seated. When fully assembled the top of the 3-5-R drum is almost flush with the opening where the pan would be and the filter would go through into the pump. Or is it a control problem? I did the Sonnax zip kit for the valve body and everything felt pretty normal. All of the rods (not sure what they're called) would spring back with the retainers in. I also did the Sonnax upgrades in the pump. I reused the TECHM. Could that be my problem? I borrowed a buddy’s scan tool and it showed that it was commanding into 4th, but it didn’t show me if the solenoid was actually engaging.
Again, sorry for the super long, and somewhat all over the place, message. But I am sort of at a loss and not sure where to go from here. Any help would be greatly appreciated, even if just a direction to go!
