I own 2 4Runners, a 2019 my wife drives and I drive a 2023. I do my own maintenance and when changing my oil I noticed I am developing deep rust around the radiator frame on the underside. I live in South Texas and never go anywhere near sand. Yet I have way too much rust for a 3 year old vehicle.

When looking closely it appears that Toyota glued foam in a couple areas where the skid plate attaches to the radiator support. I assume to reduce sound. Well that foam holds water against the metal frame and I have some deep rust in that area. The metal is actually pitted in that area from the rust. That foam does a god job of keeping the metal wet and promoting rust.

I pulled off the foam in a couple areas (which was wet from rain earlier in the week), cleaned it and put rust converter on it. I’m going to paint it with Eastwood Rust Encapsulator. While I was at it, I cleaned up my skid plate (the one that you have to pull off to change the oil), and painted it with rust encapsulator. It was rusting too although it was really just surface rust.

I am trying to maintain both my 4Runners so they will last me another 10 years. For you guys in the rust belt this is no big deal, but I should have minimal rust and only surface rust at best.

Anyway, if you have a 5th gen 4Runner you might check those areas.

Thank you for the reminder!

I had read about that foam a while back, and forgotten it.

a mod you may consider, is redirecting the AC condensation drain tube. it drips right out of the fire wall onto the frame. Many videos on it. super easy. I noticed on my 2020 4runner and 2017 Tacoma it was dripping onto the frame causing surface rust. I'll be doing the same on my 2021 LX570 so its not an isolated design aspect

quote:

Originally posted by snwghst:
a mod you may consider, is redirecting the AC condensation drain tube. it drips right out of the fire wall onto the frame. Many videos on it. super easy. I noticed on my 2020 4runner and 2017 Tacoma it was dripping onto the frame causing surface rust. I'll be doing the same on my 2021 LX570 so its not an isolated design aspect

Thanks, I did not know about that - I am going to look at it and do that too.

Yes, that’s a good one.
We did that within a week or so of getting a 5th Gen.

Woolwax or similar product - as long as it's a liquid film rust inhibitor. Load that stuff all over, it will creep whenever it's hot and repair itself when you take a chip. Reapply every year or two and rust is not a problem.

Here nor there, but several years ago I scoured the internet for a first gen Tacoma that wasn’t a “Northern” vehicle. That salt and snowy/rainy weather cratered many frames, etc to the point I thought they shouldn’t be sold, but scrapped. I don’t remember the facts now about Toyota’s solution for that major problem.

Because of this being a known and a possibly widespread problem,is your problem covered in the extended rust perforation warranty?

Toyota ended up replacing a lot of rusted out frames on those Tacos. But that program ended five or six years ago.

I’m sorry but I have no solution for the OP’s rust problem. I agree with the suggestion to ask Toyota to fix the problem under the rust warranty.

Interesting thread. We are considering buying a new 4Runner or maybe even get rid of my truck and buy a Tacoma

Had a 4Runner back in the '90s. Got that rust on the skid plates, too. Ended up removing them. I wasn't driving any place where I would need them and dropped some weight off the car.

On the bottom of the 5th gen tailgate are two hand pockets. People pop those out and used compressed air from a long wand to blow the accumulated dust out of the bottom seam. The 5th gen collects a lot dust on the gate and rear glass. It settles or washes into the tailgate.
I believe there also a purge air pump filter mod that some do before the OEM foam filter deteriorates and ruins the pump.

I have a 2017, I'll need to crawl under her in the morning and take a look.

Thanks for the tips for these 5th gen 4Runners. FYI I just added a Frantz universal bypass oil filter to my 2023, if anyone is interested let me know and I can share how I did it. I plan on running extended oil changes with oil analysis.

quote:

Originally posted by jljones:
Interesting thread. We are considering buying a new 4Runner or maybe even get rid of my truck and buy a Tacoma

I traded my 21 Tacoma TRD in for the 4Runner. I always wanted a Tacoma so I bought a well optioned one brand new. Every time I drove my wife’s 4Runner I regretted buying it. the 4Runner has more room and a better seating position. I like the 4 liter V6 verses the 3.5 V6 in the Tacoma too.

quote:

Originally posted by mrvmax:

quote:

Originally posted by jljones:
Interesting thread. We are considering buying a new 4Runner or maybe even get rid of my truck and buy a Tacoma

I traded my 21 Tacoma TRD in for the 4Runner. I always wanted a Tacoma so I bought a well optioned one brand new. Every time I drove my wife’s 4Runner I regretted buying it. the 4Runner has more room and a better seating position. I like the 4 liter V6 verses the 3.5 V6 in the Tacoma too.

See now that’s where the worry is. We have a newer 4Runner that we drive just about everywhere. And I *think* I would rather have another 4Runner in place of my truck. She says we need a truck on occasion. Truck is a 10 year old ram with 120k on it. Been paid for several years

quote:

Originally posted by jljones:

quote:

Originally posted by mrvmax:

quote:

Originally posted by jljones:
Interesting thread. We are considering buying a new 4Runner or maybe even get rid of my truck and buy a Tacoma

I traded my 21 Tacoma TRD in for the 4Runner. I always wanted a Tacoma so I bought a well optioned one brand new. Every time I drove my wife’s 4Runner I regretted buying it. the 4Runner has more room and a better seating position. I like the 4 liter V6 verses the 3.5 V6 in the Tacoma too.

See now that’s where the worry is. We have a newer 4Runner that we drive just about everywhere. And I *think* I would rather have another 4Runner in place of my truck. She says we need a truck on occasion. Truck is a 10 year old ram with 120k on it. Been paid for several years

I need a truck only a couple times a year. For now I can rent one from Home Depot or Enterprise if I need it longer. My long term plan is to buy an old truck when gas prices surge (which I think will be later this year). I figure I should be able to pick up one of the gas guzzlers (Ford or Dodge V10) for cheap when people start dumping them.

The only downside I see for the 5th gen 4Runners is the engine, I wish it was a V8. But, it is proven to be reliable for many miles. I am contemplating adding a ProCharger to mine when I retire.

quote:

Originally posted by mrvmax:

I need a truck only a couple times a year.

I prefer the SUV, and have had Pathfinders before, and a '19 4runner now. I bought an older, used utility trailer for ~$100 that is used for dump runs, mulch, moving motorcycles, etc. If you have a place to store a small trailer, I highly recommend it. I just realized i've had the trailer over 20 years - refinished it when I got it, and again about 6 years ago. It just sits there until I need it, and it's good to go.

An more on-topic - Thanks for the notice, looks like i get to drop my skid plate and take a look under there.

TAKE IT TO THE DEALER AND MAKE THEM FIX IT UNDER WARRANTY. No way, shape, or form would I accept anything less than the dealer and Toyota fixing it, under warranty on a 2023 vehicle.

I agree. For several years, Toyota was recalling Tacomas for rust issues.

I already did it myself, the dealer I bought it from was too incompetent to fix a steering wheel vibration so I do not trust them at all. I did it myself so I know it was done right. I caught it soon enough before there was any long term damage and removing the foam prevents future issues.

Every oil change I can easily see where the rust was so it is easy to monitor in the future.