2021 CX-9 Signature spare tire/lug nuts


2021 CX-9 Signature
Alright, so around 200 miles on my new CX9 Signature and I ran over a box cutter blade that somehow found it's way into our neighborhood streets. Luckily I was less than 1/4 mile from home and was able to turn around and get it home before the air leaked out.

Upon getting home I was going to put the spare on but I realized that the lug nuts are far too stubby to tighten the spare tire onto the car! 😡

I didn't take a photo but there had to be a good 3/8 of an inch or more left of the lug bolt/stud to go before the stock lug nut bottomed out. Has anyone else come across this? I called my salesman and he told me he had never heard of this issue. Which tells me either he's lying or that no one has brought this to his attention after purchasing a car from him. He's been in Mazda sales for 12 years he says. Anyway, he told me to bring the car in and show me what the issue is and he'll fix me up but all that is running through my mind is what if I had taken this thing on a long road trip and found myself on a busy interstate or something after hours with my wife and 5 year old only to find this out at that point?

I'll consider myself lucky it happened at home and for now take his word that he will find me a solution when I head up there in a day or two.
I’m an advocate of full size spares on road trips. I don’t want my trip to be thrown off by having to stop in some no name town to get a flat fixed. I can’t really help with the donut spare not fitting as I think they are dumb and won’t use them unless absolutely necessary. I have gotten a nail and a screw stuck in a tire on road trips on two different occasions and still drove on them fine. They were slow leaks and I just used my air compressor to fill them back up every 50-100 miles until we got to where we were going. I don’t know the maximum size of tire that can fit in the spare area, but I’d get a 5th wheel and a skinnier tire that hopefully fits in the spare area. The last vehicle I had that had a donut, I was able to cram a matching wheel and a 20MM narrower tire in the spare area.
Mazda CX-9 Grand Touring 2016
Go to any auto parts store and buy set of lug nuts that are open ended. You'll be able to get the spare on tightly with these. And it'll be a cheap fix. You'll need to match the angle of the cone on one end, the thread diameter, and the thead pitch (how many millimeters per thread). The auto parts clerk probably can find the spec when looking up expensive chrome nuts, and use this spec for cheapo steel nuts. They're usually sold in packs of 4, and 4 will get you to the tire shop. Forget the dealership. The salesman knows sales, not cars.

Now...I'm off to check my spare wheel & lug nuts....
Mazda CX-9 Grand Touring 2016
My nuts are just the right size. I put the compact spare on my 2016, and the lug nuts tightened the wheel to the hub just right.

It was a good exercise to take the spare out. The biggest problem was disconnecting the cable for the subwoofer that sits in the middle of the spare. The connector has a small tab, maybe 3/16" across. Press that 'til your thumb hurts, then press harder. The connector half will be able to be pulled off. Before returning it a thin smear of silicone grease on the outside of the inner part will help it come apart next time. The lug wrench for the wheels is the wrench for the spare tire hold-down bolt. The white nylon strap in the tool kit is for strapping down the damaged tire for its trip to the tire store. Check the owner's manual for the tie down points in the back of the car. Check the air in the spare yearly. A flat spare tire is no good at all. 60 psi is needed. I do not know why spare tires are always mounted with the valve on the hard-to-get-to side of the tire.