Toto drake models mismatch

[RShen]

Hi,

I plan to change the builder toilet to Toto. I'm interested in a dual-flush system, particularly an ST746SMA 1.6/0.8 tank (or EMA 1.25/0.8). However, after I purchased a CT746CUG online, what I received is a C776CEFG. I contacted seller and was told that they no longer carry CT746 because it has been replaced by C776 line, and that C776 will work just fine with the dual flush tank system. I called a Toto tech support but was told that these two won't be compatible.

I am confused with those two contradictory answers. I would hope parts of the drake models are functionally interchangeable and only numbered differently for design reasons. So will one be able to install ST746SMA on C776 with no issues (bolt positions and all)? Will it work just fine? Is it true that CT746 is discontinued?

Thank you.

 

[Jdrive]

There are 3 versions of the Drake (not including the separate "Drake II" product line).

CST744 - original model that was in market for many years, recently discontinued
CST746 - a redesign of the original Drake with terrible performance and reviews, pulled from the market only a year or two after launch
CST776 - latest 2021 redesign of the Drake

We have installed countless CST744 series Drakes and they work flawlessly (many still performing well with no call backs after 10+ years in service). The CST776 has received good feedback on this site, though we have not personally installed these yet.

I would highly recommend just sticking with the 776 series Drakes. Unfortunately, I don't think there is a dual flush version, just the E for 1.28gpf and S for 1.6gpf.

 

[Sponsor]

 

[Tuttles Revenge]

I have the 746 installed and have been using it now for 2-3yrs. I've never once used the 1.6 flush, just the .8 for everything. But the two are designed to work together. Less water in the bowl means less water flushed in the 0.8 cycle.

The biggest complaint that I've heard was that the water spot for the 746 was too small and people had to deal with skid marks not getting washed clean. the training video that Toto had indicated that would not be a problem but it obviously was. The issue you might have with the dual flush operating on the 1.28 is that the 0.8 flush might not clear the bowl. But as Terry points out, holding the handle down for a second longer adds a bit more water to clear the bowl.