I've been reading this forum for a few years now, but just now stumbled on something specific that I can't seem to find in search, so just looking for some help.
2008 P71, 170xxx miles.
The car has been beautiful for me over the last few years. Bought it with 150k or so, and did all the fluids at that time. I've redone the entire suspension, replaced engine mounts, and the #4 coil specifically more than a few times.
However, I think my transmission may be toasted. A few weeks ago it started slipping out of first gear. As in, I'd put it into "D," hit the gas, and it would go forward in first for a few feet before PING whrrrrrrr it's in neutral, until it would suddenly grab first gear again and lurch forward. The first day this happened, I checked the fluid (still perfectly cherry red, only 10k miles old or so, and at the proper level) and all transmission sensor connections.
It did it a few more times, not better or worse when warm or cold, so I did a full fluid swap using the cooler line, and I swapped in a uhaul pan with a drain and a fumoto valve. New filter. The magnet had a fair bit of fluff on it, about as much as it did three years ago when I last changed the fluid.
Then, it started doing lazy 2-3 shifts, or doing this thing on the freeway where I'd slow down from 70 to 60 or so and it would jump back and forth between 3rd and overdrive in a rhythmic motion. Clunk clunk clunk clunk as it searched between the two.
This entire time, it hasn't thrown any transmission codes. Turning off OD does not help the issue at speed, or in first gear.
At this point, I think I'm toast. I live in a studio apartment, and don't have the time, space, money, or skill to do a transmission swap or even a drop and rebuild. Junkyard transmissions are around $600 in my area already pulled (Arizona), or 350 for a DIY pull that I don't have the time or tools for. And shops all want $1000+ to even pop a new one in.
The only info I have otherwise that, if I put the shifter into first or second-gear only, it is fine? Putting it into "1" puts it SQUARELY into first gear with zero issues. Can still chirp tires and be stupid. And putting it into "2" (aka "the road is covered in ice" gear) still lets me take off in second, and it doesn't hunt or shift or seem to slip at all.