Friendly reminder for first track day of the season: Tighten your lug bolts
05-30-2012, 07:08 PM
#1
Drifting
Thread Starter
Friendly reminder for first track day of the season: Tighten your lug bolts
I feel foolish having done this, but thought I'd share in case it saves others from the same mistake. It seems every year, I forget something at the first track day of the season!
This year, after getting a new set of tires put on (my last set of Toyo RA1's!), I forgot to check the lug bolt tightness after the first on-track heat cycle. On the third session of the day, while chasing a GT3RS and Turbo, the steering started to vibrate like I lost a wheel weight. I drove through that assuming it was just that.
After a few more laps, the car was still fast, but becoming unpredictable, oversteer in one corner on one lap, understeer the next lap in the same corner. The times were still good (about 1 sec off my best) so I kept going assuming the tires were breaking in.
After a few more laps, I could feel a thumping so I decided to slow down to see what was up. When I slowed down to about 20mph, the thumping turned into very loud bangs. I pulled off assuming I broke the gearbox or diff, but didn't see any fluids. Slowly (and very noisily) I drove back into the pits, to find the wheel bolts were loose by about 4mm on the left side and 2mm on the right side!
Moral of the story, I know for a fact the shop torqued the bolts down before I headed to the track, so I was at fault for not re-checking them after the first on-track heat cycle. The other thing I learned is that, even with the wheels pointing in different directions, the lap times can still be good, albeit requiring a lot more work to extract them.
Anyway, I'm an idiot. Please don't be one too
This year, after getting a new set of tires put on (my last set of Toyo RA1's!), I forgot to check the lug bolt tightness after the first on-track heat cycle. On the third session of the day, while chasing a GT3RS and Turbo, the steering started to vibrate like I lost a wheel weight. I drove through that assuming it was just that.
After a few more laps, the car was still fast, but becoming unpredictable, oversteer in one corner on one lap, understeer the next lap in the same corner. The times were still good (about 1 sec off my best) so I kept going assuming the tires were breaking in.
After a few more laps, I could feel a thumping so I decided to slow down to see what was up. When I slowed down to about 20mph, the thumping turned into very loud bangs. I pulled off assuming I broke the gearbox or diff, but didn't see any fluids. Slowly (and very noisily) I drove back into the pits, to find the wheel bolts were loose by about 4mm on the left side and 2mm on the right side!
Moral of the story, I know for a fact the shop torqued the bolts down before I headed to the track, so I was at fault for not re-checking them after the first on-track heat cycle. The other thing I learned is that, even with the wheels pointing in different directions, the lap times can still be good, albeit requiring a lot more work to extract them.
Anyway, I'm an idiot. Please don't be one too
Last edited by fc-racer; 05-30-2012 at 10:23 PM. Reason: Made the heading more descriptive
05-30-2012, 07:16 PM
#2
Rennlist Member
Join Date: May 2008
Location: Somewhere in a galaxy far, far away....
Posts: 17,107
Likes: 0
Received 258 Likes
on
172 Posts
this can also happen to those who still use the factory 5mm spacers.... the heat expansion of material can cause em to back off the factory lugs..
I would not expect this to happen once the wheels are properly torqued 
05-31-2012, 08:52 AM
#5
Rennlist Member
I always recheck them after the first on track session. Wish I could say the same about swapping to street wheels for the ride home. Makes a funny noise on the highway when they're lose 
05-31-2012, 09:23 AM
#6
Addict
Rennlist Member
Rennlist Member
I feel foolish having done this, but thought I'd share in case it saves others from the same mistake. It seems every year, I forget something at the first track day of the season!
This year, after getting a new set of tires put on (my last set of Toyo RA1's!), I forgot to check the lug bolt tightness after the first on-track heat cycle. On the third session of the day, while chasing a GT3RS and Turbo, the steering started to vibrate like I lost a wheel weight. I drove through that assuming it was just that.
After a few more laps, the car was still fast, but becoming unpredictable, oversteer in one corner on one lap, understeer the next lap in the same corner. The times were still good (about 1 sec off my best) so I kept going assuming the tires were breaking in.
After a few more laps, I could feel a thumping so I decided to slow down to see what was up. When I slowed down to about 20mph, the thumping turned into very loud bangs. I pulled off assuming I broke the gearbox or diff, but didn't see any fluids. Slowly (and very noisily) I drove back into the pits, to find the wheel bolts were loose by about 4mm on the left side and 2mm on the right side!
Moral of the story, I know for a fact the shop torqued the bolts down before I headed to the track, so I was at fault for not re-checking them after the first on-track heat cycle. The other thing I learned is that, even with the wheels pointing in different directions, the lap times can still be good, albeit requiring a lot more work to extract them.
Anyway, I'm an idiot. Please don't be one too
This year, after getting a new set of tires put on (my last set of Toyo RA1's!), I forgot to check the lug bolt tightness after the first on-track heat cycle. On the third session of the day, while chasing a GT3RS and Turbo, the steering started to vibrate like I lost a wheel weight. I drove through that assuming it was just that.
After a few more laps, the car was still fast, but becoming unpredictable, oversteer in one corner on one lap, understeer the next lap in the same corner. The times were still good (about 1 sec off my best) so I kept going assuming the tires were breaking in.
After a few more laps, I could feel a thumping so I decided to slow down to see what was up. When I slowed down to about 20mph, the thumping turned into very loud bangs. I pulled off assuming I broke the gearbox or diff, but didn't see any fluids. Slowly (and very noisily) I drove back into the pits, to find the wheel bolts were loose by about 4mm on the left side and 2mm on the right side!
Moral of the story, I know for a fact the shop torqued the bolts down before I headed to the track, so I was at fault for not re-checking them after the first on-track heat cycle. The other thing I learned is that, even with the wheels pointing in different directions, the lap times can still be good, albeit requiring a lot more work to extract them.
Anyway, I'm an idiot. Please don't be one too
05-31-2012, 01:01 PM
#7
Burning Brakes
This same thing happened to my buddy in his M3. He came in to have me drive his car because there was a vibration. I took it out and no sooner then 40mph I was like "what the hell!" I took it right back in and checked the lug bolts. All loose enough to finger tighten on the right side . . .
