Well I here are my 2c.


Lets clear that we talk about Differencial failure not engine.

If his engine got damage after 6ms thats fine and will be his fault no doubt but we talk to diff.

Let say u don't know about truck and u are not in to DIY staff, so you are going to shop you are paying and expect they to finish the job how suppose to, so u are there and they replace the diff. oil. Well I am opening my manual and is said nothing for checking the diff. oil every 250miles as it says for the engine oil.
It says check the Diff. oil every 15,000miles or 12mts whichever comes first and replace it every 30,000miles or 24mts.
Now whos fault is. I am saying the shop.
Isn't that the reason we are going to the shop, because we are no sure or we don't have the right tools to do it,well some of us as myself doesn't trust and check everything after that but thats is just 1% of the people the rest 99% doesn't do it and they trust the shop and they read actually the manual.

we can agree on this topic forever but we can compare the engine with the diff.

Ivan