Horst Dynamic Tank Probe, Gray Water, C

After years of guessing how much grey water was in my tank, I installed a set of these. After about 6 months of use, so far, these are still working perfectly. This is actually too short a time for a comprehensive evaluation as over time crude does continue to accumulate in the tanks interior. After all, even the inferior factory ones do work for at least some time period.The grey tank has been our absolute limiting factor for needing to seek services. This grey tank fills faster than we deplete our fresh water tank and we can usually run the generator if we need to top-off the batteries. Just having working grey tank sensors will give us about an extra day before we need to seek services. This will save us a LOT of money, paying for these sensors many, many times over! (The grey tank is about 1/2 the size of the fresh tank and we never accumulate much in the blank tank. Another possibility, a method to pump grey water into unused black tank capacity would give us an additional day or two before needing services. But we need to know accurate tank levels to do this. These sensors make that mod a reasonable possibility!)I am amazed that I do NOT find LOTS of complaints about tank sensor problems. To me, this was perhaps the largest 'unresolved, unnecessary problem' of motor-home living. Maybe there is some miracle solution that I never found or maybe everybody just installs these? I was not finding evidence of this. So far, to me, this product, has become that solution, eliminating one frustration of RV living. (I am peeved because they sell us a product that certainly will fail to work correctly. This is irresponsible.)

These fixed my tank gauges reading full almost all the time. It did take some effort to get the old ones out but these took 2 minutes to install after that. the whole project took +/- an hour. My camper has a cover on the bottom so I used a video probe on my phone  USB Borescope, Depstech Semi-rigid Endoscope Inspection Camera 2.0 Megapixels CMOS HD Waterproof Snake Camera with 6 Adjustable Led Light - 16.5FT  to locate the probes. Then I cut holes that matched 8" hatch covers used on boats. The opening was large enough to get my hand in and the screw on lid meant I could check it later for leaks. Much easier than removing the corra\ugated plastic bottom. If did it again I would just punch the old ones into the empty tank, flush it and recover them that way. Will update my review if they stop being accurate.

Sadly...I cannot really rate how well these work because I could not install them as described...hence 3 stars. I could not re-use the existing 3/8" hole per the description because the old existing sender REFUSED to be extracted after completely loosening its compression net. Apparently, the rubber plug was "set" in a "too-fat-to-fit-back-thru-the 3/8" hole" situation....the old "Roach Motel" syndrome: easy to install into a clean new 3/8" hole...but impossible to get it back out! Another option is to drill 4 new 3/8' holes into each tank and install the Horst probes in the new holes...leaving the original probes as "plugs" in the original holes. Well- there was no drill access to the tank walls...too close to the frame. I'd have to drop the tank. Not to mention that I really did not like the idea of drilling 4 new holes each of my tanks. My RV is a 2012. I was really excited about these...but it was just not worth the effort and the damage risk to install them. I returned them unused...maybe they will end up in your rig and solve the age-old tank gauge problem for you!

Easy to install and I now get correct readings on my tank

Arrived quickly easy to install my son installed it

Fairly easy to install depending on how much you have to do to get to the tanks.

So far so good. the tank thickness was a full .25 so I had to hold a lot pressure while I tightened it up but it seems to be holding.

Seem to work pretty well. Get some false readings but way less than before.