How A Michigan Man Uses A Cheap Welder To Keep His Toyota 4Runner Family Vehicle On The Road After The Frame Began Rusting To The Ground

That’s sheetmetal that has basically just turned to brown sand.

Then there’s the bottom of his frame rail, which looked okay (see left image) but actually wasn’t, as Jamie found when administering a few light taps (he later cut the holes in the bottom of the frame to fit patch panels).

After many years of camping in a midsize pop-up trailer pulled by an invincible 2004 Mazda MPV, our family of 4 decided to shop around for a larger camping trailer. We quickly chose the model we wanted but with a weight of nearly 5,000 pounds we also needed a more capable tow vehicle. Luckily this was in fall of 2020 before vehicle prices went fully bonkers. My wife’s parents were considering an upgrade to their 2014 Ram 1500 and would have sold it to us at a great price if we were interested, but “full size” trucks/SUVs are just too enormous for our liking. Plus with us having no intention of starting a landscaping or construction business, we had no need for a pickup truck anyway.

As any good engineer would do, I then created a matrix of midsize SUVs that would be able to tow our desired camper and gave them weighted scores for different attributes. The top three vehicles were the Dodge Durango, Jeep Grand Cherokee and Toyota 4Runner, all of them with V8 engines. It then came down to the 2 factors I care about the most: Price and reliability. After some searching on the usual car sites, it was obvious that an 03-09 V8 4Runner was going to cost a lot less than the much newer WD/WK sisters. And with the “million mile” 2UZ-FE engine in the 4Runner along with a vastly less complicated electrical system, it was a no-brainer that the older Toyota would be more reliable than the newer Chryslers.

So while I started hunting for the perfect 4Runner, my wife began searching for a camper. The summer of 2020 saw record RV sales nationwide as people saw camping to be a COVID-safe vacation plan. We couldn’t find a new or used trailer we wanted within at least 500 miles and it seemed people were at the mercy of dealers and putting down deposits to order new trailers to be built. We pretty much decided to go this route and my wife asked in a Facebook group dedicated to Michigan camping for recommendations of dealers in the Ann Arbor area that would be good to do business with. She got many recommendations for dealers, but one person commented and said that they were thinking about selling their camper rather than putting it in storage for the winter. It just so happened to be the exact model we were looking for and this person lived 20 miles from us. The camper was one year old, in perfect condition and they floated us a price that we knew was fantastic. We sealed the deal a few days later. However, I hadn’t even looked at a single 4Runner yet. Oof.

So with all rear seats removed, the rear suspension airbags inflated to max pressure and an electric brake controller freshly installed, I headed 20 miles west to pick up the camper with the MPV odometer showing 304k miles on its all-original drivetrain. Should you tow a ~4,600 lbs trailer with a minivan that has a 3,000 lb maximum tow rating? No. Can it be done safely in a pinch for a short drive late in the evening with light traffic? Yes. Safety third, right?

With the camper purchased and safely parked in the driveway a day before Thanksgiving, my urgency to buy a new tow vehicle was actually pretty low since we had no plans for winter camping. I figured I’d just keep an eye out and wait for the right 4Runner to show itself. At the time the only one I saw nearby worth possibly considering was a private seller who had traded it for some other vehicle and “hadn’t driven it all that much” and said “it seemed to run great.” Not an ideal candidate. I then realized that I had somehow forgotten about the OG of cheap used car listings, Craigslist. With low expectations I put in a search and saw this as the one local result:

268k was definitely more miles than desired but I figured for that price on a known-durable machine that was 45 minutes from home, it was definitely worth a look. Once I got there and took a drive, I knew it was the one. Plus the small used car dealer provided the Carfax report and it showed a long history of timely services that were primarily done at the Toyota dealership. The timing belt was fresh, the radiator was new, it had brand new wheels and Michelin tires, all fluids were clean and it drove like a dream. The interior showed a little wear but overall was in good shape with no funny odors. The only thing left was to get a look at the frame since I knew Toyotas of this vintage were known to have rust issues.

With a small hammer in hand that I brought along I clunked on the frame in multiple areas and everything seemed quite solid. Sure, there was some visible surface rust here and there and I could tell there was fresh black spray paint on a lot of the visible areas but nothing that seemed to be hiding any defects and the same thing I’d do to make it look better to a potential buyer. $4,900 seemed more than fair so I took it home for that price. With it being early December and my small garage filled with kitchen renovation items, I didn’t have the opportunity to inspect it much more. A few weeks later we drove it to Chicago for Christmas and it did great, handling some snow along the way like a boss. I proudly showed it to my father-in-law and told him I’d much rather have something like a 4Runner that’s way more sensible to drive every day compared to his huge pickup truck.

Since I could park in their garage while visiting, I ordered some “Woolwax” rustproofing spray to give the frame a coating and protect it from future corrosion. All was going well until I got underneath the rear of the vehicle. This is the bottom of the frame rail just behind the rear axle. This is not the sort of thing I want to see on a vehicle that’s going to haul my family and 5,000 lbs of camper to summer vacations.

I sprayed it with rustproofing in anger and tried to not feel too deflated. After all, I got it at a good price and already knew it ran great. Plus I own a welder and I’m pretty handy with it, even if the resulting welds from a $99 Harbor Freight machine don’t look very pretty. I was all set to design my own repair pieces and have them laser-cut at Alro Steel, but then I saw people recommending “Saf-T-Cap” frame repair sections (see below). While this was going to cost a fair bit more than welding my own individual pieces together, I decided that it was worth the time savings and would ultimately end up being a stronger and easier repair. It was still a PITA job but turned out great. I coated everything in POR-15 and felt good about the truck once again. We took many camping trips in 2021 and the 4Runner handled them with ease.

These days I work from home and still have the MPV so I decided to park the 4Runner for the winter unless the roads were completely salt-free. Sure, a 4WD 4Runner would be better in the snow than a FWD minivan but we also have my wife’s 2016 Outback on snow tires if winter travel is really a concern. I figured why get any salt in that 4Runner frame if I don’t have to. Fast-forward to March of 2022 and I realized that was a very good decision. What started out as a mission to “clean up the visible surface rust and give the frame some more rust protection” quickly turned into a huge repair project. Any form of hammering on the bottom of the frame resulted in clouds of rust nuggets and dust pouring out of the intentional drain holes and small rust holes that had developed in the steel. With more hammering, chunks fell off. I eventually grabbed the angle grinder and cut most of the bottom out on both sides of the vehicle. The sides of the body mounts were even turning to dust.

  

Since the rust was so widespread, I decided to prioritize. Sure, having the bottom of a rectangular frame rail rotted-out is a bummer, but did it greatly affect the rigidity or safety of the vehicle? This former automotive engineer says no (many vehicles make do with C-channel frames, as you may know). But what can be a big safety issue is if suspension points or loaded mounting areas are compromised. So first I repaired the crusty body mount areas.

The next area of concern was the forward mount for the rear lower control arm (see below). I could see some small rust holes had developed and sure enough most of the frame in that area was rusted to hell. After getting all the rotten steel cut out, coating everything in weld-through primer and creating the necessary patch panels out of thick steel angle and plate, I welded it all back together. A few days later we hitched up the largest UHaul cargo trailer you can rent and took it to Chicago to move a bunch of furniture from my in-laws house and back to our place in Ann Arbor. As always, the 4Runner worked flawlessly.

 

While I still have plenty of cutting and welding left to do in order to have the frame of our 4Runner 100% “perfect,”with each repair I do it makes the overall task seem less daunting. Replacing rusty steel with fresh thick steel isn’t all that hard, it’s just time consuming. I may end up swearing at the truck and the universe while I lay on the garage floor under a shower of welding sparks but it never pushes me any closer to the concept of spending a large amount of money each month on a new vehicle.

For me there’s a ton of satisfaction in fully owning the vehicles I rely upon and being the only one to keep them in order. Last week we celebrated 10 years of owning our 2004 MPV (now with 316k miles), a $6000 vehicle that brought our 9 year old son home from the hospital and our 11 year old daughter has no memory of the brief time when she was alive and we didn’t have it. To me cars are more than the sum of their parts, they’re capsules of memories and experiences that are worthy of the effort it takes to keep them ready for the next adventure.

-Jamie