But what im saying is that I had no problems what so ever during that 100k..

On top of that, I got the car at almost 80k THEN put my 100k on it..

I knew the exact maint history of the car when I got it and there was nothing really..

I bet I could have ran it into the 300k range easily but I upgraded before I could ever say for sure..

Make of this what you will, my ONLY argument is that its not as bad as you say and I suggest it.

 

I think it should be expected with GM v6s of this era that parts will begin to fail near 100k (starter, alternator, coil packs, gaskets, etc) getting worse as you near 200-250k, at which point the car is worth so little that it's typically not worth dumping more money in. I would say it is out of the norm to have a catastrophic failure at 100k though, the engine should generally last to 200k+ as long as you're willing to keep fixing the smaller stuff.

However, the reason I caution about the sample size of 1 (since your two 3.4s are very different engines, it doesn't make sense to lump them together anymore than an LT1 and a LS1 since they're both a 5.7) is that there are a couple other factors at play that could cause a one off engine to come apart much earlier:
-manufacturing defect (a void in a rod casting, a bad bearing, improper heat treatment, etc)
-owner care (both in keeping up with PM and in how the car is driven)
-just plain luck (getting parts with less favorable tolerance stackup, getting a bum oil filter that unknowingly lets debris back into the engine, etc)

I would think if you averaged the life span of hundreds of 3100s and hundreds of 3400s, the average lifespan should be pretty similar as the two engines are extremely similar as far as I know.
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I did some research. if a combination of pics and wikis are telling me the truth, the LA1 3400 v6 (which is what you are after) was in fact used in the 02-05 Buick Rendezvous. You should be good to go.

 

To the OP - Sorry to lock this thread, if you have more questions, please feel free to start a new thread and ask them.

To everyone else who went off topic about the reliability of the LA1 3400 (and this includes myself), I am locking this thread as it has gone off the rails. If you wish to continue this topic about the reliability and comparisons, please feel free to open a thread on that topic. We all have different experiences, knowledge and opinions on the matter. Happy to let everyone share those in a thread of that topic.