Could use some advice...07 Yukon Denali XL, original 6spd trans with 104k miles. Unknown trans service history but vehicle was very well taken care of overall when I acquired it at 102k miles. Just did the front and rear dif and the transfer case fluids last week which i believe were probably about due judging by the color of the fluid. No chunks came out just some really fine shavings as I would expect. Magnets looked good.
Drove 10 hours this weekend and noticed on occasion if doing say 60mph and I needed to quickly pass someone at near WOT, it will downshift several gears with a very loud and violent bang. If I ease in to it, it downshifts smooth as silk. Upshifts 1-2 & 2-3 are sometimes harsh at very slow speeds but nothing too concerning. I also have quite a delay from reverse to drive on occasion...roughly 1.5 seconds after putting it in "D" it will finally shift. Which of my concerns are normal complaints of the 6spd? The different forums I checked concerning the 6l80 are all over the place on these issues it seems with some having them since day 1 of their new vehicles. I plan on doing a complete fluid transfer and filter service soon but will hold off if anyone thinks I have bigger problems. Thanks
Drove 10 hours this weekend and noticed on occasion if doing say 60mph and I needed to quickly pass someone at near WOT, it will downshift several gears with a very loud and violent bang. If I ease in to it, it downshifts smooth as silk. Upshifts 1-2 & 2-3 are sometimes harsh at very slow speeds but nothing too concerning. I also have quite a delay from reverse to drive on occasion...roughly 1.5 seconds after putting it in "D" it will finally shift. Which of my concerns are normal complaints of the 6spd? The different forums I checked concerning the 6l80 are all over the place on these issues it seems with some having them since day 1 of their new vehicles. I plan on doing a complete fluid transfer and filter service soon but will hold off if anyone thinks I have bigger problems. Thanks
