Not a whole lot of interesting Mustang-related things have been going on lately. I added an oxygen sensor awhile ago for tuning, but it’s just a narrow band and I haven’t been able to get even slightly consistent results from it. Otherwise, I’ve just been driving it a fair bit more and actually treating it like my only car. I’ve had it on the highway a few more times, and it’s definitely getting better mileage since I swapped back from my ~0.067” carb jet to an 0.064”. I think I’m getting somewhere between 15 and 20 mpg on the highway now, but I haven’t had a tank where I predominantly drove highway only.

The problem is that the slight vibration noticeable in the shifter and a little throughout the car overall around town gets quite a bit worse on the highway. Now that I’ve been paying a little more attention to it, I think it’s more proportional to engine rpm rather than speed. If I take it up to 3000-3500 rpm in 2nd, it seems about as bad as it is at 3000 rpm in 3rd. So it’s probably something in the clutch/transmission/driveshaft, but I’m not sure what specifically.

So today I decided to pull the transmission and check things out. I don’t see anything obviously wrong. I’d sort of like to swap my old transmission back in to see if it goes away, but that’d require relocating dowel pins and swapping pilot bushings. Not things I really want to do unless I need to… so I guess I’ll probably take a better look at it tomorrow and then put it back together for now.