Mile Marker for NP203 transfer case conversion….thoughts ?

[SilverMiner]

Originally Posted by kwmech

One of the main issues ---back in the day-- was of course the continual spinning of the chain with a heavy truck which managed (believe it or not) to stretch the chain to the point of it being able to jump the gear and eventually break, blowing the chain case part of the t-case out of the bottom.

http://67-72chevytrucks.com/vboard/s...d.php?t=545961

In the 80's I inherited via my job the responsibility for a 16 vehicle fleet of mining exploration vehicles that mainly consisted of 70's squarebody trucks, Blazers and a couple of Suburbans. All were extremely high mileage with a sketchy prior maintenance and all were abused in the way that only mining company rigs used in the Norther Rockies can be. All had original and unmodified NP203's. Although a number of the 100K mile + rigs eventually had chain problems, none resulted in a blown chain case. I do believe such things have happened to other people, but it has never happened in my experience which is odd given how poorly geologists and mining engineers traditionally treat company trucks.

You would have to have absolutely zero mechanical sympathy to allow a loose chain noise to persist long enough for it to result in a blown case. That is a level of abuse I have fortunately never experienced. I can only imagine those same idiots would listen to an NP205 with drained lubricant whine until the gears fused together.

Neither fault can be attributed to the transfer case - abnormal use brings about abnormal results.