I love it! I thought my 17,000 2002 Formula was clean underneath, but I think you have me beat. I replaced my tires after 14 years. They looked brand new and had less than 9k miles on them, but it's better to be safe than sorry. Thanks for sharing!
2 things- 1 - your tires are too old, regardless of how much tread you have, replace them, my car is also a 2000 Trans Am, when driving the car liked to wander going down the road, even though the steering wheel was straight, was also getting noise from rear end, kind of a wah-wah-wah-wah, that got faster with speed. Bought new wheels and tires last year, got them installed, car now tracks straight and no more noise from rear end, I looked at the date on the tires - 2914 - 29th week of 2014!! My tires also have great tread as its been driven 32k miles. But after so many years, the rubber tends to break down. 2 - when you do a rear diff service, make sure you can remove the fill plug on the front of the rear end housing. Hate to get rid of all the fluid, button everything back up and the plug is so rusted you can't get it loose.
That's why I pointed out the tires haha I think it's time for some Continentals this time around.. shame BFG doesn't make these tires anymore, they're fantastic. As for the diff fluid.. that's a good thought, I wasn't too worried in my lower mileage cars.. but I need to do my 66 Rambler and my 74 Sierra next.. I will definitely keep that in mind, I agree, that would be an absolute pain to run into. I can think of a couple of work arounds, but not ones that I would prefer to have to do. lol
