My better half and I were driving our 99 Trail Blazer (145k miles) from Scranton to Pittsburgh during a blizzard, this past Christmas week. We pulled into a rest area and when I let off the gas there were a couple of bangs from drivetrain. I did some slow backups and go forward, no noise. There was about 6 inches of snow in the parking lot and tons of the stuff on the freeway so I thought maybe I had some ice build-up that fell off when I stopped.

We continued on our way, no more noises. The next day we were driving around Pittsburgh and it started making seriously ugly noises. I limped to a garage that a local buddy uses and recommended. I was hoping/praying it was only a u-joint. No such luck. Mechanic says the transfer case had gone cannibal and was digesting itself. He checked fluid levels and said it was real low/empty, and that there was a seal leaking pretty good.

He made some calls and found 2 NP-236's, one with 100k for $500 and one with 60k for $750. He quoted $300 to install it. Being it was Christmas, money was already tight so I said a prayer and picked the $500 unit. After he got the unit in he called me and told me the seals on it “looked okay”. I told him to replace them anyway,as it would be way cheaper now than later.

Because of what you guys have said on this forum about the critical importance of using AutoTrak II in these type cases, I reminded him to flush whatever was in that case and replace it with fresh AutoTrak II. He said, “Dexron is fine for those cases, no need to spend the extra money on GM’s fluid.” I carefully and calmly repeated my request and he said okay. Afterward, when I went to pick it up, he told me he did some research and found what I was saying was true and apologized for not already knowing that.

Truck runs great now, no vibrations at all, no rumbling, just smooth quick shifts into and out of 2 Hi, 4Hi and 4Auto.

Anyway, there are three morals to this story:

1. My TBlazer got me all the way to Pittsburgh before it croaked and didn't strand me along the interstate in a blizzard, bless her sweet heart. Thank God for that.

2. This forum educated me to know the importance of AutoTrak II. Thanks for a great forum!

3. Check your fluids!

 

That's good you wearn't stranded on the the side of the road in a snow storm. I've learned a lot from this forum also. There are many many smart people that are more than willing to help. I to would like to say thank you to everyone and being a part of a great forum.

 

Wow. If almost any aspect of that story changed, you would have been in for a world of hurt. Way too many chances for that to go anyway but good. Glad you opted to patch her up. The TBlazer is a sexy beast and there are too few of the originals left.