It has been a very big point of contention within the Q50 community about Infiniti’s choice to opt for run flat tires on the Q50. Not only do run flats ride harsher, cost more but they have a low thread wear rating of 280AA which translates to 18,000 miles only. Lastly run flats are great if you “plan" on having protection against getting a nail/screw etc, but if it ends up being a side wall damage or damage due to a big pothole or other object then the run-flat tire is pretty much useless. Call me old school, but one one the first things my dad taught me was to change a spare on a car before I could even drive the car - secure car with chucks, loosen lug nuts, jack up, remove flat, replace with spare, soft tighten lugs, lower jack, fully tighten lug nuts, off you go.
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| Hybrid Trunk WITH Spare underneath. |
The set on my Q50 managed to last about 22000 miles with proper rotations and had about 4/32nds of thread left, while not below the legal limit of 2/32nds, and anyone who lives in a snowy winter place, knows that is just asking for trouble. So before winter I decided to go with non run flats and based on the reviews and research on Tirerack.com decided to get a set of 4 Pirelli Cinturato P7 All Season Plus Radial Tire - 245/40R19 98V have thread rating of 700AA or 50,000Miles and also features eco drive, low rolling resistance technology. I got mine from Amazon and they were at my door step in 2 days. It cost another $98 to have them mounted and road-force balanced.
Overall the ride has been much better, much quieter, much smother and much better snow and rain traction.
This means I really do not have a need to the styrofoam insert that Infiniti gave me on my Q50 that does its job of simply occupying 3” of already limited trunk space and serving no purpose but to hold a toe hook…seriously?
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| What a waste of space |
Trunk without the junk
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| Built to have a spare |
Instead I decided to use the space to put a real spare in there. I looked at the prices from Infiniti parts to get a Q50 3.7 spare with Jack, and proper inserts which would need to be modified and it was well over $1000 dollars, I think I’ll save that money to get buy those set run flats when I trade in the car in a few years. In the meantime I hit ebay and got myself a spare removed from a G37..complete wheel and tire, it had all but 1 scuff and had never been used, got a Nissan Jack and it came with a set of tools and bag for cheap.
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| Spare from G37 Model, Clears Front Caliper |
I double checked to make sure that it would clear the front caliper by actually mounting it on the car and bingo!
The tire/wheel that clears the Q50 Sport front and rear calipers is Enkei 18x4T Wheel with Maxxis T145x70R18 Tire.
The tire/wheel that clears the Q50 Sport front and rear calipers is Enkei 18x4T Wheel with Maxxis T145x70R18 Tire.
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| Spare Tire that clear 19" Sport Calipers just fine. |
Put the spare tire into the back on trunk into the depression that was obviously made for the spare tire and it fit perfectly, I put it face down, so that I would have space to put stuff into the wheel such as the tool bag and finally the jack upside down into the wheel hub space.
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| Fits nicely into the Q50 Hybrid Trunk |
What was needed next was some pieces of styrofoam inserts to all the trunk mat to be level and sturdy. Rather than getting 3.7L Q50 model inserts for hundreds of dollars and modifying them, I hit home depot, got a sheet of insulating foam board 2” thick and cut it into 3 shapes, one for the left of the spare tire, another for the right and another rounded to fit into the wheel with a slot for the jack to go upside down. Glued them up and saran wrapped them to let them cure, into shape. These are rough cuts right now When they cure and I have mode time, I can actually hollow out the left and right inserts to provide storage space to hold a 12V tire Inflator kit or jumper cables or whatever.
The bottom of the jack is level with the side inserts and it provides a very sturdy surface in the trunk for cargo as it transfers the weight directly to the wheel which is in direct contact with the body. And I can stand on the foam inserts without making a dent.
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| Home Made inserts that cost less than $10 and get the job done. |
Put the original trunk mat back and Viola….a Q50s Hybrid with an OEM spare tire, jack & tool set and net loss of space has ben just about 2 1/2 inches from the bottom up.
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| Spare Tire in Trunk |
I still get just over 18” of vertical space..more than enough for my daily needs 90% o the time. I have had no issue having to roller-board suitcases and carry on bag i there.
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| Trunk Mat Moves Up by about 2.5" on the battery side |
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| Not losing too much space with a spare. |
I feel a heck of a lot safer knowing that no matter where I am traveling, no matter what time of day or night and in which remote area, I don't have to be stranded because of a flat tire and i don't have to ride on less than desirable run flats.
