How much frame rust is too much?

I just bought this 03 Sr5 v8 with really low mileage in amazing condition but I’ve been reading about the rust issues they have and wanted an opinion on it. I have no idea how much is too much, and if I should take preventative measures to help extend the life. It’s at 100k miles and I’d like to have it for a really long time. Thanks so much in advance !

 

Hi Maya, welcome to the forum.


The rust doesn’t look too bad, but get it treated

 

Welcome to the forum!

It doesn't look too bad but a little fluid film treatment should keep it from getting worse.

There are other products that last longer but I find fluid film applied every 6-12 months works well for my area.

 

This is not ideal, but doesn't look structural. If you simply start applying Krown or Fluid film each year, you will likely can get 10 years or more out of this frame. No, it won't last forever as rust already started.

Looking at the picture, I'd be more concerned about alignment bolts not coming out.

 

@Sin4R ok thank you, is it easy to do yourself or should I get a professional to do it ?

 

You can buy it in spray cans and do it yourself. I'd put some paper down to catch any drips.

 

Its not bad but hope you used it to negotiate it lower.

You can do it your self it you don't mind getting under there.

 

It is messy but not difficult job. If you can pay someone to do, I would. Make sure they use oil-based product like Krown. It drips and leaves mess behind but effective at slowing down rust. Just make sure to avoid tar-based undercoating like Ziebart.

 

Never mind the rust, I can't stop laughing at your screen name.

 

Hey, not bad rust there really, for that year.
I’m currently sanding surface rust fairly similar to some of your photos. You wanna first degrease it, sand with wire brush / wire wheel, then metal prep and “paint”.

Effective diy rust treatments are available at all auto parts stores and are fundamentally easy yes. Like anything, products come with different levels of difficulty/labor (and $$$).

I’d say if you’d call yourself a handy, and, frugal person, do it yourself on the street and protect the area including yourself from overspray & drips.

 

I paid 5k for it so , I thought I made away pretty good for a 4Runner

 

At 5K, could pay a shop to do a Krown treatment for you. Some folks swear by shop Krown treatments. Wool Wax is very good too.

 

Sounds like a steal for a working 4Runner with no other issues.


You didn't ask, but I will mention just in case. Make sure you know when each fluid was changed. Thing is, people tend to not do maintenance when they know they are about to sell the car. Unless your truck came with records, assume that every maintenance item is overdue.

In order of importance:

1. Change engine oil and filter.
2. Change brake fluid and service brakes
3. Change transmission fluid
4. Check engine air intake filter
5. Check alignment and tires, don't forget to check spare.

Less important, but still very worthwhile to do:

6. Change differential oil
7. Change transfer case fluid
8. Change cabin filter
9. Change power steering fluid
10. Change spark plugs
11. Run high-PEA injector cleaner (e.g. BG 44K in a tank of ethanol-free gas)
12. Inspect radiator hoses, accessory belts, check radiator for leaks

 

I live where they salt roads a lot. Everything rusts here, but I apply Krown every fall since new and my cars are rust-free. It is messy, it can drip and stain driveway, but it is worthwhile to not have to deal with rust.

 

Welcome to the forum and congrats on purchasing a 4Runner. I have seen much worse for rusty frames. Yours is still manageable if you do as others have recommended.

I would add the need to treat the inside of the frame rails. The 4Runner uses a boxed frame which is stronger than a c channel type frame but is difficult to get rust protection into and is often overlooked. I know that Fluid film can be bought in a spray can form that includes a spray tube that is inserted into the frame rails. It's tricky to use but better than nothing.

I am fortunate that I found a reputable rust prevention shop in my town that does a thorough job, which includes inspecting those frame rails with a scope as well as occasional touch ups, like after replacing a part.
https://www.gottschsgoo.com/

If you can find a shop in your area that does something similar, I'd expect the cost to be less than $400. Note that these are not long term treatments. If you use Fluidfilm and apply it yourself, expect to do this annually to maintain it's effectiveness. The treatment I have on my 4Runner lasts about 18 months. Depending on where you live and the types of roads you drive on, more frequent treatments may be required.

Ultimately, practicing these methods will drastically prolong the life of your 4Runner.

 

this! ^
well said
*also rinse out your frame rails first with a pressure washer or hose

 

Careful with a pressure washer, depending on the nozzle and distance it can lift/strip paint inside the rail.