When to seek arthritis treatment?

Snowball is ~10 years old. He is, I think, in excellent health. I'd never really noticed any stiffness before, other than several hours or so after he'd had significantly more exercise than normal (but really, who isn't stiff after hard exercise?)

Recently, however, he has started to become wary of getting out of the back of my husband's hatchback and balks at going down stairs unless he thinks he's getting a walk or a car ride out of it. We thought it was a behavioral thing, e.g. negative feelings because he's slipped on the stairs when they were icy and he was very excited, it can be awkward to get out of the car in our parking lot because if the car pulls in forward, the lot slopes away and its a larger drop than normal, and if we back in, Snowball has to jump over a parking block (or possibly throwing tantrums because 9/10 times we're coming back from somewhere fun that he didn't want to leave, i.e. Grandmas). But now I'm wondering if they both are the result of developing arthritis in his hips.

ANYWAY, my question is, to those of you who have older dogs, and especially dogs with diagnosed arthritis, at what point did you start actively treating it? And for those of you in cold climates, do the signs change with the weather/cold/rain? Off-leash he will still run around like a maniac; should I be limiting the intensity of his exertion? Any other general advice (outside of go to the vet - I'm going to ask if he thinks we'd benefit from an appointment right away vs. at the yearly checkup in June when I see him next week for the cat)

As soon as I started asking myself this question.

I say if it's having an impact, treat it. Zoe will have been on meds for 7 years this summer - since she tore her CCL. We didn't do them every day at first (after her recovery from the TPLO, that is,) just as needed. I think that may have helped her not build up tolerance, and kept things easier on her liver/etc.

She is on both Meloxicam and Tramadol now. We added the Tramadol maybe 18ish months ago? She is doing wonderfully. I like natural, but meds give my dog so much comfort and happiness.

And yes, weather changes, cold weather, rainy weather, they seem to be tougher on her. Cold snaps especially, though part of that is having a metal plate in her leg. She also limps more when stressed, but this could just be the distraction breaking down her tough pibble barriers.

I am careful about high impact activity, but mostly because she is too old to put her through another TPLO if her right side were to tear. She goes for long walks every day, and her vet says lots of low impact movement is the best thing for arthritis. I would say if he likes to run around, let him, and get meds to help. They have a cumulative effect, so you can pre-dose for hikes/etc. if you aren't giving them every day. High dose fish oil also seems to help.

It can be tough starting meds or upping meds because then we have to admit our dogs are aging, but I have been lucky to have a vet who is really into joint issues and has arthritis himself, and it's been a positive experience getting Zoe treated. I even asked him about laser treatment last year at her wellness exam and he assured me she wasn't bad enough for it to be worth my money. He did say there are injectables that should help as she has more pain. It's nice to know there is still more out there.