Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations KootK on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Should I be worried about wheel load ratings? 2

JackCharvel

Geotechnical
Aug 24, 2024
6
I've been looking to upgrade wheels on my 2012 Toyota Sienna LE FWD 3.5L for a minute now and am wondering if wheels off a lighter car are safe to use. We're talking GVWR=5,995lbs vs maybe 4,700lbs. So basically the heaviest vs lightest vehicles with 5x114.3mm bolt patterns. I've reached out to Toyota directly and through dealerships, they say we don't test wheels across all models so we can not recommend swapping them, they won't give up the load ratings at all. I've found there are 2 camps, one says if the bolt pattern matches you're good to go (speaking of load only/not considering offset or clearance issues), and the other says that it's a safety issue and you'd be taking a risk. The specific wheels I'm thinking about getting now are '20-'24 Rav4 TRD 18" wheels (PN-PT758-42200, PN for my stock wheel is 42611-08070) But I've considered Camry, Lexus IS, and other manufacturers wheels that have popped up on marketplace with 5x114.3. I found an ebay listing here with pics of the identifiers stamped in the wheel. Nothing about load rating however.

Ultimately, I'd like to find out how to look up wheel load ratings for any vehicle. I think it's a safety issue to not make the info available. If the wheels are overrated, fine. If not, we could confirm that a wheel is not safe. Why would they hide this info from us?

Some other things occur to me that are probably relevant:
-Toyota Racing Division (TRD) packages are common for off-roading, would it be reasonable to assume that these wheels would be over built compared to standard options?
-If there is no definitive answer to be had, could I make a reasonable assumption based on wheel weight across models? (other dimensions the same obviously)
-How common are wheel failures if the max load rating is exceeded by my possible 25% excess?
-What failure mode would be expected for an overloaded wheel in this scenario? (How risky is it?)
Thanks for any input!
 
Replies continue below

Recommended for you

I think I answered this question on another website. I go by the name CapriRacer a lot, so this might be a repeat. Nevertheless, here is my understanding about wheel loading:

There aren't any regulations about wheels being marked for max load and pressure. I've asked around a lot and the best I can come up with is that wheel manufacturers design wheels to be able to holdup the largest load for the largest tire that fits the rim - and they test for that.

In your case, it means that any wheel that fits your vehicle will have been tested for the worst case. Wheel failures are very rare. I've only seen a few. Not anywhere near what I would consider worthy of concern. The fact that there aren't any government regulations seems to point to this not being a problem.
 
I think I answered this question on another website. I go by the name CapriRacer a lot, so this might be a repeat. Nevertheless, here is my understanding about wheel loading:

There aren't any regulations about wheels being marked for max load and pressure. I've asked around a lot and the best I can come up with is that wheel manufacturers design wheels to be able to holdup the largest load for the largest tire that fits the rim - and they test for that.

In your case, it means that any wheel that fits your vehicle will have been tested for the worst case. Wheel failures are very rare. I've only seen a few. Not anywhere near what I would consider worthy of concern. The fact that there aren't any government regulations seems to point to this not being a problem.
Thanks for your input. That actually makes sense since a manufacturer shouldn't want a wheel underated per the tire making it's way onto a heavier vehicle. I posted this on a reddit engineering group too and one guy went into some math regarding fatigue limits and strengths and used (what I'm assuming is) a typical safety factor of 7. Here is a link to that thread in case you're interested.
 
I think I answered this question on another website.
Because he has posted this exact same thing before.

 
Because he has posted this exact same thing before.

Well the same topic with some distinctly different and more detailed considerations. I didn't realize CapriceRacer responded on my old closed post til now.
 
Yes, One should be aware of the correct load index of wheels and the correct load rating of tires. Several Transit Connect owners, in the hunt for wheels for their vans are turning to the snowflake designed Focus wheels. These focus wheels are not load indexed to work on the van. Because the van is heavier than the Focus and add in weight if towing or hauling, One is looking for strutal failure of the wheel at some point.
 

Part and Inventory Search

Sponsor