91 Four-Runner lock-up Torque-Converter ??

[vicegrip]

Well I sure like my daughter's 4-runner .....gass millage could be better??

but I used it this week-end ......and darned if it didn't seem like at a relaxed throttle @ cruiseing speed a little press on the pedal pepped the engine sound , but the tack stayed syncronis with the speed-ometer ..........Hmn ...only other cars I ever had do that had Lock-up torque-converters .....don't have a book on this puppy yet

Any facts ??

Have a good Week
Phil J

Wonder if the differensials could run on Mercon (tranny-fluid) in the winter for better M.P.G.???

[MrFriggsit]

Yup, this vehicle has a lockup. A touch of the brake pedal when you are at the speed where you can feel a direct connection should dissengage the clutch momentarily, and you should see a small RPM change. Most cars and light trucks since the mid 80's have TCCs, for gas milage. Don't know about the mercon in the diffs though. You maybe could try one of the exotic synth multi vis gear oils, like a 75-140w. They seem a little thinner cold, and the newer trucks seem to be using it. Can't go wrong with what the owner's manual recommends though.

[vicegrip]

Yup, this vehicle has a lockup. A touch of the brake pedal when you are at the speed where you can feel a direct connection should dissengage the clutch momentarily, and you should see a small RPM change. Most cars and light trucks since the mid 80's have TCCs, for gas milage. Don't know about the mercon in the diffs though. You maybe could try one of the exotic synth multi vis gear oils, like a 75-140w. They seem a little thinner cold, and the newer trucks seem to be using it. Can't go wrong with what the owner's manual recommends though.

Reply much appreciated.....very unfamilliar with this Pup .....as for the diff's .....i've seen old machinery with gearing that has WAY more strain on it do OK when the owners needed to keep lube in Em' (lealy) and not go to the poor-house paying for the oil the 45 year-old warrenty calls for .....

This was a low-cost vehickle .... ( City auction ) I think it was a get-away car (very strange bruises high up on the body) , and bizzar personal effects left inside ...........Hmmnnnnn ......maybe I should pull off the liners in the doors

Phil j.

[Toysrme]

I would. It get's crap for eocnomy becuase it has a junk engine in it.
Toyota's designed one engine in the last 40 years that simply has engineering mistakes in it. It's the 3vz-e 3.0L v6 in your 4runner.
It get's crap for economy. It has basically an ounce of power compaired toe very other Toyota v6 made. It habitually blows up...
You better stick to cooling system maintenance like a mother ******. That's the only real ceveate of the entire drivetrain. See in the late 80's the fed banned the use of asbestos in headgasket materials. Conciquently every headgasket on an engine sold in the US from the late 80's through <whenever your preffered OEM swapped to Multi-Layer Steel gaskets> suck hind tit.
Which is a particular problem on this engine, because the poorly designed crossover pipe restricts the #6 exhaust valve port. Which will eventually overheat the cylinder head, warp the head, then blow the weak gasket.

So... Cooling system maintenance... Flush it every other year. Changer the thermostats & pressure caps every 4 years. No exceptions.
AFA the vehicle itself. The engines is just as, if not more reliable than any other equivilant engine in that segment, in that time period. And the rest of the car is so much more ungodly reliable than practically anything sold in that segment, at that time. It's just completely rediculous. The build quality (That means parts quality, and the quality of assembly) at that time was great. Higher than un-named vehicles also built in the US were doing 10 years later...

See. That's the nice thing about Toyota's. That they have historically had some strange qwirk where that feel like they must completely over-engineer everything they do. That crap 3.0L v6 makes 150bhp. Yet the actual integrity in it is rediculous for a 150bhp engine. The entire blocks will handle over 900bhp, completely unmodified. The crankshaft. Ditto. The main bearings, ditto. Then there's an extra block girdle sitting ontop of all that. The rods themselves are fine out over 500 horsepower. (That's over 80hp a rod on a 150bhp total factory output folks. Goodnight!) the pistons are... 400+ without the presence of pre-ignition.

Now the cams suck, and the implimentation of the SOHC heads is completely horrible compaired to the Yamaha (Toyota owns Yamaha) designed dohc fe heads. But that's besides the point. Heh. The entire rest of the drivetrain is like that. The axles, driveshafts & differentials by other's standards are still quite large. The hubs are golden if you have the right set. The transmissions will hold boatloads of power provided you keep fresh & cool fluid. The list goes on & on.


What I'm trying to tell you. Is that if the vehicle is in actual top condition. The only excuse for it mechanically dieing, is owner/maintenance neglect.
This coming from a Toyota technitian. And you wiiiiill pop that head gasket the very first time that coolant gauge reads hot. You won't save it. Don't even think you will LoL! Just do the maintenance. Timing belt & water pump every 90,000 miles.



And yes. You're really going to hate that engine LoL! The DOHC version in the camry (3vz-fe) shares very little parts wise, but is *so* close. Same generation engine block family... It has a minute amount of extra compression, but the DOHC head & intake only provide an extra 50 horsepower & 1500rpm to the rev limit. LoL! And the 3.4L 5vz-fe v6 that replace your 3vz-e completely walks you in every aspect you could imagine.






So don't worry about the low mileage & practically ball-less feel of the engine. That's normal. Remember 150hp ish v6's were the wide standard in the late 80's for light trucks/suv's. And it could be worse...

[vicegrip]

I would.Toyota's designed one engine in the last 40 years that simply has engineering mistakes in it.................So... Cooling system maintenance... Flush it every other year. Changer the thermostats & pressure caps every 4 years. No exceptions.
AFA the vehicle itself. ................See. That's the nice thing about Toyota's. That they have historically had some strange qwirk where that feel like they must completely over-engineer everything they do. ...................
So don't worry about the low mileage & practically ball-less feel of the engine. That's normal. Remember 150hp ish v6's were the wide standard in the late 80's for light trucks/suv's. And it could be worse...

As a toyota mechanic in prehistoric times ....and based on driving this thing so far , your post seems like a bulls-Eye , Thanks for the detailed evaluation.....

Phil J.

[Masher Mfg]

Don't use ATF in the diffs, it would work for a little while but ring and pinion failure would result. The reason diff gear lube stinks is because of the sulfur and other additives. These are high pressure lubes that coat the gears providing lubrication even when the base stock oil is pushed out of the way.

Use full synthetic gear oil if you want to make a change ( Mobile 1 is good, Redline racing oil is way more that you need ) I use Mobile 1 in the oval track car with good results.

The electric car guys monitor all power going into and out of their battery packs, they report less drag when using synthetic gear lubes.

The number one item that affects fuel mileage is how the car is driven! BMW did some testing and found from a dead stop 70% throttle opening and shifts just past the torque peak gave the best fuel mileage. The shifts are at a much lower low RPM that you would use in normal acceleration and feel just on the edge of lugging the motor.

As a side note the auto trans in your Toyota is the same/similar as the similar year Jeep.

[Toysrme]

That's because an engine has the highest volumetric effeciancy with the least restriction. I.E. and open throttle on a gas engine.
Unfortunately, you can't do that on almost every production engine as once you pass 75-80% wide open throttle on your gas pedal. The ECU will go from closed loop (Oxygen sensor feedback), to open - loop (stored map, no feedback - it will run richer for power & safety)

Once you get passed the Prius & several members of that engine block family. You won't find another engine in the US that runs closed-loop 100% of the time. I can't name one off-hand.







And it's not just raw accelleration. It's coasting & speed amangement also. If you drive the exact same way just with more throttle until you get to the same speed. Your mileage will out right decrease.