I had somebody back in to my tacoma going 5mph. It tweaked the bumper a bit & I didn't think much of it. I took it to a shop & the frame had been bent - a lot. Once it was on the lift I could see what really had happened.
I guess what I'm saying is that you can take the money and go play...
How do the 2003-2009 4runner suspensions compare to 3rd gen? Would there be any advantage to changing them out if you could get it for really cheap? It's stock front & rear + springs.
Personally, that's when they started using more plastic than metal in the body. It's mainly a cosmetic thing... Plus we're all jealous that we can't afford one.
Full Disclosure - I used to work here:
Call 1-800-Radiator. They'll have Denso and Koyo in stock and depending on where you live, they'll even deliver. Price-wise they can usually beat internet prices. You can also get it same day and if you have problems, they'll swap it out instead of...
Looks like a wholesale nameless radiator. They are going to package whatever they can find in their own boxes and sell it to you. my biggest concern with that would be that you have no guarantee. If you buy a Koyo- or similar brand radiator, you'll get the guarantee.
I worked at a radiator...
I've had this problem with vehicles in the past & it drives me crazy. I had to tear apart a dash once to find it. Problem is that it could be just about anything. Luckily it isn't that hard to tear it apart in a 4Runner, so give yourself an hour to find it. Let us know the results.
The other half of the equation is how 'motivated' you are to sell. If you have time, post it for a higher price and wait.
Check local Craigslist sales of similar vehicles to see how fast they are moving. It's surprising how much regional variation there can be for vehicles.
Seasonality...
I've had similar experiences in the past on other vehicles. I ended up needing to replace bad u-joints. If that ends up being the issue, make sure you get Spicer brand joints.
It humms? Maybe it doesn't know the words? More info needed. Is it a sound that only happens while moving? Does it change if you speed up or slow down? Any vibration along with it? Are you in 2WD, 4WD? Does your vehicle have rear diff?
I know that pricing is somewhat regional and seasonal, but 3500 doesn't seem bad. Make sure you can have it checked out before you pay anything. Taking it to a mechanic & having them do safety & emissions is a quick way to get past 90% of the problems that can be hiding in the vehicle.
I worked at a radiator wholesaler for a few years. I can vouch for koyo radiators. They are much higher quality parts.
Also, if you want a better deal on a radiator (or a transmission cooler) go to a wholesaler.