Neighbor has a 14 Forester. I have done the last few tire rotations. Every time, the lug studs shed an abnormal quantity of metal shavings.
At the most recent tire rotation in August, one of the lug studs snapped off when I torqued the lug nut. It was replaced with a Dorman stud and nut. I torque the lug nuts to 89 ft lbs per the FSM. All of the other ones were fine.
Several days ago, he went to Costco for new tires. Costco refused to touch the vehicle and said two lug nuts were seized.
Upon further research, it seems like this is not an uncommon issue with Subaru vehicles:
Furthermore, there was a recent TSB from Subaru about rusting lug nuts:
Honda/Toyota use 12x1.5 lug studs; Subaru uses 12x1.25. I wonder if the issue is a combo of the rust, finer threads and poor metallurgy of the studs? I plan to replace all of the remaining lug studs and lug nuts with the Dorman ones to prevent the issue from reoccurring. However, I am curious if others have experience with this issue and have any thoughts on why it occurs.
At the most recent tire rotation in August, one of the lug studs snapped off when I torqued the lug nut. It was replaced with a Dorman stud and nut. I torque the lug nuts to 89 ft lbs per the FSM. All of the other ones were fine.
Several days ago, he went to Costco for new tires. Costco refused to touch the vehicle and said two lug nuts were seized.
Upon further research, it seems like this is not an uncommon issue with Subaru vehicles:
Broken Subaru Lug Nuts and Lug Studs
Why do Subaru lug nuts seize and why do lug studs break? What can you do to prevent it from happening again?
artsautomotive.com
(All Years) - Problem with wheel studs? (merged thread)
www.subaruforester.org
Furthermore, there was a recent TSB from Subaru about rusting lug nuts:
Honda/Toyota use 12x1.5 lug studs; Subaru uses 12x1.25. I wonder if the issue is a combo of the rust, finer threads and poor metallurgy of the studs? I plan to replace all of the remaining lug studs and lug nuts with the Dorman ones to prevent the issue from reoccurring. However, I am curious if others have experience with this issue and have any thoughts on why it occurs.
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