Hi All, I have been reading through the forum on several topics,and one that really caught my attention was the tranny issues. My 09 GMC has either a 80 or a 90 trans., I do not have my paperwork with me, and I do not remember.

Here are my questions. My tranny has a temp moitor and what shold it run and what is the max temp before issues start? I do not know where the reading is taken from,and I assume that would be important too. It has a factory installed cooler and it is in fromt of the radiator on one side and the engine oil cooler is on the other side, I believe. All that came with the trailering package.

2nd question is this,since the trans. comes with Dextron VI synthetic fluid I assume that will help matters of longjevity,is that true? At some point, early, less than 10,000 miles, should I drop the tranny pan and change the filter and send fluid off for analysis? Is any one filter better than the stock GM filter?

This is my bottom line, I plan to keep the truck for a long time and really do not want tranny issues, if I can help it. What can I do to prevent them and what are the problems to look for?

Thanks, MPC

Well congrats on the nice rig first of all. Denail's are sweet and my favorites in the GMC line-up, as for the technical details, I bet a gear head around here not me could help you. I wonder if this wouldn't get more attention in the tech section. Let some of the gearheads around here chime in first.

Hi MPC! I moved your topic to the tech section of the boards. I don't know the answer to your question but hopefully someone here will...

Well I had tranny problems with my Grand Prix, and I had it rebuilt to handle more power. But the transmission shop I went to recommended changing the fluid once a year.

Thanks for the move and I have not asked the dealer yet either. I wanted an Idea of what the real world thinks before I move on to GM on the issue. One would think the Owners manual would have that temp indicated somewhere,and maybe I just overlooked it. Thanks again for the move. MC

Thanks for the reply, It has not gone over 161F so far. It has been up to 97 degrees in our part of the world. I still assume that the temp is taken at the right area through GM Research. When I ask the dealership it will be interesting to see what they say. MC