Swollen lug nuts

Just adding my 2 cents. My sister has a 2011 Sienna with a 128k miles. She just had a recall done at a Toyota dealership and they advised her that the front brakes pads were at 1mm! She declined repair and asked me to confirm that the pads were needing replacement. I tried to use the factory lug wrench (21mm) to remove the front wheels. The lug wrench didn't fit the lugs!!! WTHeck?? Fortunately I had a 22mm impact socket with a 1/2 breaker bar and was able to remove the lug nuts. Long story short....the Sienna had "swollen lug nuts". After replacing the pads on all four wheels, I did some research and discovered that this is a major problem for other makes as well. I can only imaging having a flat tire, pulling out the factory lug wrench, only to discover it no longer fits!!!! Wow!! My solution was to purchase a set of 20 aftermarket, one piece design, chrome lug nuts for $20 on eBay. Same style of lug nut just one piece, not a steel inner lug nut with a capped finish alloy and now the factory lug wrench will work if needed. If you have a capped lug nut, you better check that the lug wrench will fit.

It looks like I've joined the Sienna Swollen Nuts Club after only 5 1/2 years. When I installed the winter wheels/tires on our vehicles yesterday, it was difficult to get my socket wrench on several of the lug nuts on our 2014 Sienna. When one of the lug nuts on the left front wheel wouldn't budge, I used my gorilla gauge breaker bar and promptly broke off the stud. I know that the lug nuts were not over tightened since I checked the torque after the last tire rotation 5,000 miles ago and when one tire was replaced under road hazard warranty in July.

I've used the same lug nuts on both the summer and winter wheels over the nearly 90,000 miles on the Sienna.

All the Sienna lug nuts look in pretty bad shape with corrosion so I'll be trekking to a Toyota dealer this morning with a Costco Auto Program discount coupon to buy 20 replacements.

The original lug nuts on our 2012 Prius v still look like new but I use different lug nuts on its steel winter wheels and the car is at only 43,xxx miles.

I'd visually compare the OEM Prius lug nuts with the OEM Sienna lug nuts but the Prius lug nuts are now in a storage compartment on the rolling tire dolly under the stack of eight summer wheels and I'm in no mood to remove the wheels from the dolly in order to compare them.

I'll compare the Prius and Sienna lug nuts at the Toyota dealership with my measuring calipers. The parts number cross reference seems to show that the Prius lug nuts have been used only on vehicles assembled in Japan. The parts number cross reference appears to show that the Sienna lug nuts have been used only on vehicles assembled in North America.

My guess is that a different lug nut supplier is responsible for the crappy Sienna lug nuts so I will see if the lug nuts for the Japan assembled vehicles can be used as a substitute. I thought about buying replacement lug nuts on Amazon but so many of them get bad reviews.

This is the earliest I've ever installed winter tires. Precipitation with temperatures as low as 20 degrees Fahrenheit are forecast for the next few days which is unusual for this time of year here.

OK, so the Toyota parts department employee I spoke with today was very familiar with the swelling and corrosion issues of the lug nuts used on Toyotas assembled in North America including those on the gen 3 Sienna - part number 90084-94001 - and he launched into a surprisingly detailed technical explanation of why they deteriorate.

When I told him that I wanted to instead buy the lug nuts that are installed on Toyota vehicles assembled in Japan - part number 90942-01033 - he told me that doing that was a known solution for the problem.

It was clear that he would have sold me the crap OEM Sienna lug nuts if I had asked for them but that he was more than willing to sell me the lug nuts for Toyotas assembled in Japan if I asked for them. He guaranteed that the ones for the Japan assembled vehicles would fit my U.S. built Sienna but I still measured them to verify.

The lug nuts for the Japan assembled Toyotas are slightly different in that the tapered portion is a slightly longer.

I can't guarantee that the lug nuts for Toyotas assembled in Japan won't have any problems but none of the lug nuts we've had on Toyotas assembled in Japan have swelled or corroded and we've kept three of those vehicles for 14 years.