T4,I haven't had a problem. In the winter the trans has kicked into OD within the same 1/4 mile as always,never had it overheat yet. I'm usually running around 150,highest was 220 with a 1500# load going uphill at 70 mph,I don't tow with my AT. I had the same concerns stacking the senders since putting them togeher in a tee takes them out of the fuild flow,but it was by far the easiest way and it worked. My gauge is digital and responds fast so it must be working right. By the way my trans temp gauge is wired into a triple throw switch,with a flick I can read AT temp,engine oil temp,and when I have time to tap a hole in my intake manifold,intake air temp. Along with my boost gauge,that also measures fuel pressure,and pyro I'm reading 6 temps/pressures with three electric gauges. Keeps the dash clutter down somewhat.
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95' 25004X4,AT,Driftwood,Banks,Warn fender flairs and running boards(Play truck)95 3500,5 speed,driftwood,Banks&phscotty,34,000 GCVW apple and tractor hauler(work truck)