Known Engine Problems?

[INSW20]

are there any known major engine problems with the 4 Runner 4.0L? reason i ask is........

granted, the head gaskets didn't fail until near 200k miles, but that's still disappointing for me. apparently it's not uncommon for the Tacoma 4.0L to develop a leaking head gasket on cylinder 5 or 6, and not unheard of to have a cracked head. since i'm looking to trade the taco for a 4 runner, i'd prefer to avoid doing this sort of major mechanical work this "early." :suspicious:

 

[marshal]

despite being the 'same' 4.0L's in the 4Runners, they're different engines. as far as i know no one in the FJ Cruisers or 4Runners have had any normal issues

 

[philsey]

^ +1

I've been on here since 2010 and have read very very few engine issues, and certainly nothing that would represent a trend.

 

[harper7]

are there any known major engine problems with the 4 Runner 4.0L? reason i ask is........

granted, the head gaskets didn't fail until near 200k miles, but that's still disappointing for me. apparently it's not uncommon for the Tacoma 4.0L to develop a leaking head gasket on cylinder 5 or 6, and not unheard of to have a cracked head. since i'm looking to trade the taco for a 4 runner, i'd prefer to avoid doing this sort of major mechanical work this "early." :suspicious:

Only known major engine problems with the 4Runner 4.0L is it's missing 2 cylinders.:eyebrows:

These are the upgrades the dual vvt-i 4.0L got over the single vvt-i in the Taco and 4th Gens.Practically a completely different engine with very little if any parts interchangeable.I don't think anybody has reached 200k miles yet on this engine but the head redesign,like the water jacket spacers was likely made to fix the single vvt-i 4.0L known potential head gasket problems.

Engine Proper
Oil delivery pipes are used for the cylinder head cover.
The cylinder head structure has been changed; the camshaft housing is
now separate from the cylinder head.
The shapes of the cylinder head intake ports and the locations of the fuel
injectors have been optimized.
The surface treatment of the cylinder block liner has been changed.
A cylinder block water jacket spacer has been added.
The shape of the piston has been changed.
A 5 balance weight crankshaft is used.

Valve Mechanism
A Dual Variable Valve Timing-intelligent (Dual VVT-i) system, in
which the VVT-i system has also been added to the exhaust side, is used.
A roller rocker arm is used.
A hydraulic lash adjuster is used.
Cam lobes with indented R profiles are used.

Lubrication System
Oil passages for the VVT-i controller (exhaust) and the hydraulic lash
adjuster have been added.
An oil filter with a replaceable element is used.
Intake and Exhaust System
The shape and installation location of the air cleaner have been changed.
A filter paper type air cleaner element is used.
The throttle valve diameter has been increased.
The shape of the intake air chamber has been optimized.
The Acoustic Control Induction System (ACIS) has been discontinued.
The shape of the exhaust manifold has been changed.
The volume and cell density of the three-way catalytic converter have
been optimized.
The material of the tail exhaust pipe has been changed.
Fuel System The fuel system is made compatible with E20 fuel.
Ignition System Iridium-tipped spark plugs are used.
Charging System A generator pulley with a one-way clutch is used.
Starting System The starter has been changed to one with a 1.4 kW rating output.

Engine Control System
A Dual VVT-i system is used.
A fuel pump control that can regulate the fuel pump speed to one of
Low, Middle or High is used.
A power steering oil pressure sensor is used.

And those are just SOME of the changes off the top of my head.Ya right,lol....here's a Toyota document from the newer FJ's that use the same engine.......View attachment 1GR-FE_Engine (2).pdf

 

[Kotrin]

I did a ton of research before buying mine and I never read anything about the 4.0L. I know its not as strong as the 3.4L due to casting differences in thickness and such. I know that the tacoma/fj/4runner are different from each one and I look forward to getting 200k ++ out of the engine. I've only heard of a few people so far with the mileage on the 4runner's, but a lot with the Tacoma's.

Opinions aside I think its really how someone takes care of their engine with some luck and what you do with your vehicle ....I guess we will see how they do in another 5 years and go from there eh?

I have zero regrets as I know i'll get 200k out of my engine and by than i'll be getting another...I will say that I do know that multiple people with tacoma's have had issues and the one's i pesronally know that he didn't change his oil properly as he should have...

 

[INSW20]

I will say that I I do know that mutliple people with tacoma's have had issues and the one's i pesronally know that he didn't change his oil properly as he should have...

you can see from how clean it is in my engine that it was certainly maintained. :first: too bad no amount of regular oil changes will prevent the head gasket from leaking coolant into #5 and causing a misfire.

 

[Kotrin]

you can see from how clean it is in my engine that it was certainly maintained. :first: too bad no amount of regular oil changes will prevent the head gasket from leaking coolant into #5 and causing a misfire.

True. Just providing the information that i'm aware of before I purchased my Tacoma and 4Runner.

Really sorry to hear that it happened though

 

[Kotrin]

On a completely separate note, I sold my Dad my old Hyundai and he's put another 20k miles on it with no issues. Some of those go forever and some die at 100k instantly..

 

[Jayhawk5G]

The only "engine" issue I have repeatedly heard from here is that the engine hasn't been given an optional TRD Supercharger.

 

[INSW20]

this is not the kind of fun i want to part-take in with the 4 Runner before 350,000 miles........ :behindsofa: (picture shown of my 2006 tacoma as of last night)

the good news is that it really did come apart rather well. now to see how it goes back together.