This is probably very old news to most but I'm shocked there isn't an easily accessible fuel filter to swap out in the 5th gen. I realize there is a large filter inside the fuel tank but I'm interested in running an aftermarket in-line filter that I can swap out every couple of years. My thinking is a second filter in the system would considerably extend the life of the tank fuel filter.

I realize this isn't "necessary" but swapping out the filter always made a big difference in my old Pathfinder, especially with the diet gasolene that we have out here in California. If I swapped out my aftermarket fuel filter in a few years and it was dirty, I'd be happy I spent the money.

This is the kit I found from 8Runner Offroad: Fuel Pump and Filter Upgrade Kit | 2010+ 4Runner – 8Runner Offroad, does anyone have any experience with it? It would be extremely overkill in terms of quality, but I love that it uses stock quick disconnects (which I also didn't know about) and no clamps involved.

Interested to hear any feedback good or bad.

Fuel will still always run thru the tank filter first, so I don't see how it's life would be extended.

I believe the 5th gen's fuel system is the old school return style so fuel is always returning to the tank. Since there is a second filter in the system, it would be returning to the tank much cleaner than it left. As you drive around, that same tank of gas is cycling through two filters instead of one. The tank filter is certainly still capturing all the largest debris from a fresh fill-up, but I'm thinking the aftermarket filter would still be taking close to half the load of filtering each tank of gas and therefore would still extend the life of tank filter.

Doesn't seem like it is a very common setup though, which is why I'm asking about it.

Yes, fuel has been returned to the tank for a long time, but it is hardly old school. It is an absolute requirement to prevent vapor lock; it keeps cooler fuel in the fuel lines.

I don't see why returning cleaner fuel back the tank is important. If the fuel is clean enough to not clog the fuel injectors, it is clean enough to send back to the fuel tank.

Any additional filtering will cause some back pressure in the fuel lines, thus reducing the fuel pressure needed at the injectors. If the pressure is lower than it should be, the injectors won't put out the right amount of gas.

I can see adding more fuel filtering in countries where the gas is inherently dirty compared to the US, but in the US, the OEM filter works just fine.

I only say Old School because more modern fuel systems do not return any fuel to the tank. If this were the case with the 5th gen, then I would be less excited about the additional in-line fuel filter as the fuel wouldn't be constantly cycled through the filters.

In terms of fuel pressure, it is a concern but at least with the Radium filter they claim a negligible change in pressure on their website.

Not needed and adds unnecessary failure point.

Looks like a good kit but I think it's one of those things that solve a problem that isn't a problem. CA gas is fine as long as you're not purchasing from a station that keeps their fuel in an open well.

It is definitely not making the 4Runner any more reliable. The only reason why I'm interested is because how big of a difference a fresh fuel filter made in acceleration with my old Pathfinder. I realize that is a completely different motor and fuel system and a ton more miles, but it made an impression when I swapped it out.

I'm under 10k miles right now on my 4Runner and just thinking down the line at 80k or 100k miles I may wish I had installed one to swap out.

I'm still undecided on pulling the trigger or not. We'll see.

Wouldnt an additional filter add additional pressure drop across the filter as it becomes clogged with debris? If the fuel pressure drops abit it may/may not effect injector efficiency. I wouldnt add it. I would just buy better gas.

The radium filter is some ridiculous premium high-flow filter that claims negligible pressure drop. Extremely overkill for what I'm looking for but the benefit is that it can use the factory quick disconnect fuel lines, at least with the 8Runner kit. So it is a concern but maybe not an issue with this particular filter.

High Flow Fuel Filters

Any fuel you put in the gas tank, has to go through the filter on the fuel pump intake. So the fuel is filtered before it reaches this add-on filter.

I don't think you'll achieve anything but a lighter wallet, and a potential source of leaks, right above the exhaust manifold...

If you want an increase in acceleration, get a tune or a pedal commander

For 300 HP, you’ll need approximately 115 LPH (30 GPH) of gasoline.

The pressure drop vs flow chart shows less than 0.1 psi pressure drop at 115 LPH for all available filter media types. So, pressure drop likely isn’t a concern for a clean filter. This pressure drop will increase as the filter captures debris.

Radium recommends inspecting the filter every 8k-10k miles depending on media type. So, you would want to add this inspection to your oil changes.

Personally, I would recommend the micro glass media as it is really the best of all world for petroleum products filter media.

Stainless steel is reusable/cleanable, but it has very little debris holding capacity and can become clogged very quickly. This would result in a big pressure drop and potential fueling issues.

My understanding of the stock fuel filter is that it’s a single layer stainless steel screen. So, more of a strainer than a filter and will only capture large particles. US gasoline has strict cleanliness requirements allowing vehicle manufacturers to forgo the addition of a fine mesh fuel filter. The strainer is not a maintenance item. Port injection fuel injectors aren’t very sensitize either. Diesel’s extremely high pressure fuel pump and injectors are very sensitive to fuel cleanliness and so require a replaceable fuel filter pre pump.

Considering the hundreds of thousands of 5th gens without this type of fuel filter and without issues caused by fuel cleanliness this mod is 100% overkill and will likely only lighten your wallet. However, if it makes you happy then do it and report your work and results.

My experience with Radium products was a Surge tank with a second pump. It was a really nice bit of kit for sure. The URD supercharger kit I installed included an external fuel filter which I put after the surge tank. I think I wrote it up. The one you picture looks very nice.

The 5th gen does return any unused fuel to the tank. In my case the engine fuel returns to the surge tank and the surge tank returns to the gas tank.

One thing I did notice was the URD supplied fuel filter did induce a whine at times as the fuel was forced through it. That may not be the case with the Radium filter you show.

The fuel line runs along the driver side frame and up into the engine bay. Where were you thinking of mounting it?

I've have about 170,000 miles on my 12 yr old truck. I've given it gas while offroad from jerry cans, filled up in sketchy gas stations in Baja Mexico. The fuel tank filter is just fine. Your looking to solve a problem that isn't there and potentially adding a huge failure point. I'd say it's not a good idea.