We are about to replace our builder grade 3.5gal flushers with 1.6 ada, elongated TOTOs. One bath has a weird quirk-when you flush the toilet the bathtub gurgles-nothing comes up in the tub just the gurgle sound from the tub drain. The old toilet has worked fine with very few plunging episodes in the past 7 yrs we have owned the house. Is this something we may be able to fix with the installation of the new toilet? Thanks to all the great info and advice here that lead me to purchasing an Ultramax & Mercer. Never though I could be excited about toilets!! Zorji