You beat me to it. This cannot be stressed enough. I was lucky to only get fake Oral B toothbrush heads to learn my lesson. Spark plugs are another big one. That being said good luck to getting your O2 sensors sorted.
Where is that comment coming from? I never once suggested these GX's are unreliable. I'm confident that my suggesting using specifications and wearable limits of parts as a hard guide to determine road worthiness is far from me being ocd as you say.
I find no harm in recommending to...
"Ran great" is very subjective. To some people anything that starts up and goes "runs great". My description of running great means almost every part of the vehicle from power train to chassis is within specifications as outlined in the service manual. Anything less is not acceptable for road...
Naturally you will get a few examples of high mileage rigs. However I call BS on trouble free miles on any vehicle that is not taken care of or beat on in off highway and everyday driving. All my 300K+ vehicles had meticulous maintenance schedules and repairs made when needed.
I will assure...
I would run away from that vehicle or any other modified rig. Miles are a big concern for anything mechanical. Unless you know the persons driving habits you are purchasing it from, you don't know how it's been treated. 145k is a lot of miles on anything used.
I actually like the bagged up air compressors that I can move from rig to rig. I'm all about simple. Some of these GX builds blow my mind on how complicated and serious fabrication is involved.
My wife and I are seriously considering a GX460. My plan would be simple and functional as a daily...
This might be a stab in the dark but do you have an in-cab mounted air compressor with lines going to air lockers? If so and your diff vents are plugged then that is your issue.