Greetings to all, we are trying to get input from knowledgeable owners and techs about engines with the cast iron blocks.
The used 4Runner we want is 4x4 and the engine is open for discussion that is why the questions.
A 2.7 might be ok and we have not owned a 3.4 or 4.0 in V6 so we need help with them especially.
When we find ones in our budget they have high mileage and do not know what to expect as to replacement parts from high miles like 150k, 225k.
Not many sellers explain the maintenance and in case they do not know or share repairs what is likely to need replacing due to mileage.
We want durability from our engine and want to be able to identify which ones have this feature. Also which ones have chains and transmission coolers on them.Someone posted that V6 engines have the coolers but we have not noticed this or it was not indicated by the seller. We are looking for a used one for daily/weekly driving. Which years have transmissions to avoid this is also where we need advice.

Many thanks to someone that can help in this regard.

I have owned a 1996 T4R now for just over a month. It has 260k miles and has the 3.4 V6. From what I have researched this motor, if maintained is fairly bullet proof. It does like to leak at the valve covers though. You also will need to change the timing belt (from what I am gathering 90k between changes is recommended from Toyota). I have not read of any other serious maintenance issues. I read in the 3rd gen forum of folks who have way more miles on their trucks than I do.

My transmission is a 5 speed manual. No problems yet although prior to buying it had to have its slave cylinder replaced. That is a common issue on high mileage trucks. The clutch feels solid but I have no idea if it is original or not.

Go to the third gen page and read the stickies, it will give you an idea on what common problems are with automatics and other parts pieces of the truck. I do know that 3.0 V6's tend to have head gasket problems based on what I have read. I don't know anything about the 4.0.

If you get one with a 3.4 you probably will not have any issues with the engine. You probably will have to deal with the brakes, steering rack, shocks/springs, radiator before you have engine problems.

IMHO of owning a 4runner for such a short time is, if it has less than 200k it really isn't high miles. These things are pretty robust because they were designed for use in a lot of crappy remote areas of the world where maintenance is not really a thought. If you find one that has been maintained and isn't rusty, get it. They will probably outlast your desire to own one.

I do not have first hand experience owning a 4.0 V6 from the 4th gen 4runner... however, referencing this recent thread:

Should I get a v6 or v8

I would expect if it had consistent headgasket problems, or unusually high failure components, it likely would have come up. From what I've read, it's a solid motor. However, like all "all-aluminum" motors... one good overheat and it might be toast.

The 3.4L (5VZ-FE) is a stout motor. I've owned two different trucks with them and they've never let me down. They drive nice, easy to maintain. I'd really struggle to find you a fault.

If you want something reliable, just avoid the 3.0L from the 2nd gen 4Runner. They're great trucks, but when those motors start having problems, they get right expensive really fast. And they call it the 3.slo for a reason.

The 3RZ-FE that came in the 3rd gens are great motors, from what little people have said about them.

To be honest, I think you wouldn't go wrong with a well maintained 3rd or 4th gen truck. Going back in time for a 2nd gen would be ok if you know what you're getting into and really want that truck/body style.