Prius rust what’s your experience ?

I had a 2009 that was totaled in 2012 with 107,000 miles, no rust. Now I have a 2012 at 122,000 miles no rust. However, MS has mild winters, no snow, no road salt, I live 300 miles from salt water, etc.

If I had to guess, you live in Ontario, Canada, and conditions will be different! (I spent 11 months in Toronto one year)

 

Including the underside, suspension components?

I was dismayed at how fast ours started rusting, in those regions. Tried commercial treatments, with mediocre results. Then brushed on boiled linseed oil, undiluted, with foam brushes, on the recommendation of @tvpierce here. It's held up very well.

April of 2015, before doing anything:



September of 2019: about a year post-application of BLO:



Better pic, just now:



I think this guy makes good points:

Linseed Oil Rust Proofing. Hazards? - Bob Is The Oil Guy

 

I'll add a new twist in my never ending saga of rust prevention.
The back story: In addtion to the Prius, I had a 2002 Toyota 4Runner (recently sold) and a newly acquired 2000 Toyota Tundra. Both vehicles are notorius for rusted frames -- to the point where Toyota will replace the entire frame on some Tundras under a recall.

I belong to forums similar to this one but for 4Runners and Tundras.

Here's a thread on the 4Runner forum started by a member (Dogtail) from Massachusetts -- a state that has harsh winters and heavily salts its roads. He swears by an annual dousing with nothing more than WD-40. Check out the thread, and his pics. The results are astonishing.

My newly acquired 2000 Tundra had spent the first 18 years of its life in California -- so was virtually rust free. It did spend one winter in Maine so had some light surface rust on some parts of the underside. This summer, I got under the truck, cleaned it up, and painted the frame with POR-15. This fall, I sprayed the frame, under-body, inside rocker panels, and inside doors with WD-40. I bought a gallon size to use in a garden sprayer, and hand pump sprayer... and a large aerosol can with an extended spray hose to get the hard-to-reach areas.

I have to say, I really like the ease of application of the WD-40. I also like that since it's not a very viscous liquid, it tends to "creep" into seams. It appears to have coated very nicely.

 

I jacked up and safety standed one end at a time, say an afternoon one week, the other end the next week. Not familiar with 4th gen, but with our 3rd gen I found it worthwhile to remove the wheels, and (especially in the rear) some of the small protection plastic panels. Some were held on by bolts that were already near-seized. I drenched those in oil before reinstalling.

 

I have lived in the heavily salted northern part of the US. Over the years, most of the cars I kept longer than 10 years on the road were decommissioned due to rust related problems at the end. This with or without professional rustproof. For any cars I have owned, including some American and Honda and Toyota, the surface rust was always visible on some components after the first winter, but serious rust related problems did not develop until the car is ~10 years or older on the roads. I recently have given a try with Fluid Film undercoating on my previous Gen3 (purchased 2015) and had it professionally applied to the underbody. It is cheaper ($130) than most of apply once type permanent undercoating treatment done professionally (over $1000), but the company that makes Fluid Filum does recommend reapplying maintenance coating every year (at reduced cost of $80). So, on the cost base, it is not much difference in the total cost after 10 years. Unfortunately, I did not keep the Gen3 long enough to see it's long term effectiveness.

I tried to have my 2017 PIRME treated with Fluid Film after trading in my Gen3 in 2017. The same shop that did Fluid Film on my Gen3 looked at my PRIME, which I think is very similar to your Gen4, and told me there is nothing they can spray underbody without removing the plastic covers. They felt it was not necessary to apply underscoring on the car. I did not pursue further at that time, but after 2 winters my car does have some components starting to show rust. Not bad, but bad enough to make me worry about the car's longevity. But if I include the labor cost of removing the plastic panels, the annual application becomes too expensive. I am thinking of trying to do it DIY, but like you, I have difficulty in raising the car high enough using just floor jack and stands. Even if I can't do the entire underbody DIY, I am planning to apply some type of rust inhibitor on the suspension components before the third winter when I do tire changes soon.

Here is my car's underside looks like after 2 winters without any treatment.

 

Looks not bad. Some components almost impervious, and a few zones not so much. Interesting. These look to be good rear safety stand points btw:



Wherever those oblong plugs are, tends to be heavy plate.

 

My Prius lives indoors.

 

The only salt I have found in Southern California is on the Margaritas.

 

Being from Minnesota, we have absolutely horrendous road salt. As I've posted around here before, we used to be loyal Mazda fans. Unfortunately, ALL of our Mazda vehicles ended up rusting through in certain spots. We have since switched to Toyota (specifically the Prius ) and I have been super impressed. No body panel rust and the underbody even looks decent (but there is some rust here and there...around here that is inevetible). There are also a large number of Gen2 Prius around here with no visible rust...which is a great sign.

I've been thinking of trying FluidFilm and/or WD40 (as mentioned above). However, the 'do nothing' approach appears to be working so far. Note that I do run the cars thru the car wash more in the winter to wash off some of the salt, etc...

 

I left a small magnet on the frame of my car - above the door near the roof - for 4 months kind of an experiment to see what of anything would happen. The steel magnet did rust through the clear coat and paint onto the frame.

 

What the hell is wrong with this car? I live in Buffalo, but I've never seen this on a 3 year old car.

 

That's distressing...

 

Ugggh - That's not your car is it?

If not, I wonder what the history of the car is - previous accident damage, windscreen replaced - or just rust. Looks like it's been resprayed, or could just be the photo??

 

Probably a stone chip very early on in it's life that hasn't been spotted and rectified.