I have the CVC BU60FHD converter, with only 5/6 TCC lockup and zero-slip. And it works quite well. It is the best value that I know for a stock upgrade.
General wisdom for 6L80 converter clutches is that the GM woven carbon clutches are the best for TCC slip, and I think that Sonnax is the only one with a comparable woven carbon material. Most other clutches do not tolerate slip as well (CVC included), which is why @NickTransmissions recommends a thicker clutch for a longer life. It does seem prudent to target zero slip with aftermarket clutches.
My own personal experience was that the CVC performed well with slip at first, but I only had TCC in 5/6. However after a 400 mile tow trip, I began to get a shudder at low rpm & high load, which I think was probably some type of burnishing of the clutches. The end result was that I switched to zero slip to resolve it. I didn't shoot for zero slip at first, because I had only chose to rebuild the trans as a preventative measure. I wasn't trying to change everything at once except that it seemed very clear that TCC lockup in 2nd and 3rd would increase the wear on the TCC, so 5/6 only TCC lockup was my starting poing.
General wisdom for 6L80 converter clutches is that the GM woven carbon clutches are the best for TCC slip, and I think that Sonnax is the only one with a comparable woven carbon material. Most other clutches do not tolerate slip as well (CVC included), which is why @NickTransmissions recommends a thicker clutch for a longer life. It does seem prudent to target zero slip with aftermarket clutches.
My own personal experience was that the CVC performed well with slip at first, but I only had TCC in 5/6. However after a 400 mile tow trip, I began to get a shudder at low rpm & high load, which I think was probably some type of burnishing of the clutches. The end result was that I switched to zero slip to resolve it. I didn't shoot for zero slip at first, because I had only chose to rebuild the trans as a preventative measure. I wasn't trying to change everything at once except that it seemed very clear that TCC lockup in 2nd and 3rd would increase the wear on the TCC, so 5/6 only TCC lockup was my starting poing.
