Here's various bits and pieces of technical specifications, etc. that I've collected about my 1985 (1st generation) 4Runner:
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66.1 (stock)~72" (lifted)
106" w/ rear spring swap
and dropped spring hanger
55.9" (F)55.1" (R)
|Fuel Tank||17.2 gallons|
|Wheels||15x6J / 3-3/8" backspace|
|Toe In||1mm ± 2mm|
|Caster||2°00' ± 1° 4Runner
2°15' ± 1° pickup
|Steering Axis Inclination||9°30' ± 45'|
|Turning Angle: Max Angle||
Inside: 30°30'Outside: 29°
|Turning Angle @20° Outside||Inside: 20°30'|
|Power||116 HP @ 4800 RPM|
|Torque||140 lb-ft @ 2800 RPM|
The Aisin Seiki W56 is a five-speed, fully-synchronized manual transmission is found in Toyota 4x4's with the 22R-E engine:
Or the A340F 4-speed automatic transmission:
The Aisin Seiki RF1A two-speed transfer case is found in Toyota 4x4's:
With a Marlin Ultimate Crawler (dual transfer case), 5.29:1 R&P gears, overall crawl ratios work out to:
With a Marlin Ultimate Crawler (dual transfer case), 4.88:1 R&P gears, overall crawl ratios work out to:
Below is some information on the 8" Toyoya 3rd members/differentials:
Here is a table of ring and pinion sizes for various gear ratios in the Toyota 8" differential:
(typical axle ratios for manual transmission equipped trucks, 28" stock tires)
|3.42||41||12||Purple||31 : 1||.||.||.||.|
|3.90||39||10||none||36 : 1||.||.||.||.|
|4.10||41||10||Pink||37 : 1||28||28||.||28|
|4.37||35||8||Green||40 : 1||30||29-30||28||28|
|4.56||41||9||Yellow||41 : 1||31||29-31||29-30||29-30|
|4.88||39||8||White||44 : 1||33||31-33||31||31-33|
|5.29||37||7||none||48 : 1||36||33-36||33||33|
|5.71||40||7||none||51 : 1||39||37+||35||33+|
There are 4 common factory gear ratios for the '84-'95 pickups and 4Runners. What ratio your truck has depends on what type of transmission it came with (manual/4 speed) or automatic) and whether it came with the factory 31" tire option (early '90s SR5 option) or the normal 28" (P22575R15) tires, as noted below:
You can look up the factory axle code for a given vehicle using this table. Or refer to the paint code on the end of the pinion flange shaft, as shown in the image below:
Note that the color codes above are not an absolute way to determine gear ratio, nor is the vehicle's model info/VIN sticker. However, if you have an axle/differential off of an unknown vehicle or it has aftermarket gears, then you'll need to determine the ratio. If the differential is out, count the ring and pinion gear teeth (or that data is often stamped into the ring gear).
If the differential is still installed inside an axle, then assuming you have open differentials, lift one wheel on the axle in question off the ground. Put the tranny in neutral, transfer case in 2H, e-brake off (if is the rear axle you are testing) and put a chalk mark on the driveshaft and on the tire. Now turn the tire in the air through 2 full revolutions, while counting the revolutions that the driveshaft makes. The number of which will be equal to your gear ratio. You can get a more accurate count by doing 10 or 20 wheel revolutions and dividing the driveshaft turns accordingly.
If you have a limited slip or automatic locker, then you'll need both wheels in the air and you'll use just one wheel revolution to get the rear ratio. For better accuracy, you can use say 10 (or 20) revolutions and then divide your drive shaft revolutions to get the gear ratio. For example, the difference between 4.56 (a little over 4-1/2 revs) and 4.88 (a little over 4-3/4 revs) might be hard to distinguish, but if you did 10 times as many revs on the wheel, you magnify the difference at the driveshaft by 10 as well. So instead of say 0.32 revolution difference (4.88-4.56), you would now have 3.2 revolutions difference if turning the wheel 10 (or 20) times.
Note that you may get different readings on the gear ratio with the above methods. Least reliable method is likely the "paint code". Next up the list in reliability is the vehicle VIN plate. It should be accurate given the diff in the vehicle is still the original one or that you know that VIN info from the vehicle the diff came out of. The wheel spinning technique should give good information with good technique. But it can give you misleading information, too. I once tested a diff I had and it seemed to do right at 4.5 axle shaft rotations for 1 pinion rotation. Fugured it was a 4.56 until I counted the teeth and found it to be a 4.10. So a tooth count is the most accurate test, but also the hardest to do if the diff is bolted up to the axle housing.
Above are photos of the various Toyota 8" 3rd member housings. All the housings are interchaneable in that the mounting studs and axle splines are identical. The 4 cyl differential internals are different than the V6 and High Pinion, so that lockers and limited slips are different. The 4 cyl ring and pinion gears are somewhat smaller overall than the V6 parts, i.e. the ring gear is thinner and the pinion gear and bearing are less substantial. The 4- and 6-cyl housings can be distinguised by the number and style of reinforcing ribs present.
The 4- and 6-cyl housings may be used in rear or front applications. The pinion (or companion) flange nut takes a 30mm socket.
The High Pinion diff uses reverse cut gears and is best suited for front solid axle applications. While it shares internals with the V6 diff, the gears are unique to the High Pinion due to the reverse cut, which puts the gears on the drive side of the teeth in the front axle. High pinion diffs are commonly found in 1990-1997 FJ-80 and FJZ-80 model Landcruisers that had the solid front axles. Ironically, the high pinion diff was not designed for the added ground clearance, but rather so that the steering tie rod on the FJ-80 could be run *below* the front driveshaft to keep the vehicle low!
Perhaps the single most misunderstood axle term is reverse cut, often mistakenly referred to as reverse rotation. A reverse cut housing is not standard cut housing turned upside down, it is a specially designed housing, most notably with internal mechanisms to aide in pumping gear oil up to the high-mounted pinion gear and bearings for proper lubrication. The term "reverse cut" refers to the direction of the spiral cut in the ring gear, which is opposite that of a standard cut ring gear. Contrary to popular belief, it does not run backwards or in reverse. The principle behind a reverse cut is to strengthen the operation of the gear when it is used for a front driving axle application. See below for an illustration of the ring gear tooth nomenclature and construction. As you can see, the drive side of the gear tooth is nearly perpendicular to the direction that the pinion gear tooth pushes on it, making for an efficient transfer of force. The coast side on the other had, is angled away from the direction of force, this causes the pinion gear to want to "ride up" on the ring gear teeth under load, lessening the area of contact and moving it out towards the thinner ends of the teeth vs. the thicker root of the tooth. As such, it is generally the case that a ring/pinion gear set is 30% weaker when run in the reverse direction. This is not normally a problem, as you rarely see the kinds of loads in reverse that you see when going forward. Likewise, a front axle usually has less load on it that a rear axle, like when climbing up some steep obstacle (i.e. less weight and traction up front) so its common to run a rear differential in a front axle. The 4- and 6-cyl gears will run on the coast side in the front axle, likewise, a high-pinion, reverse-cut differential will run on the coast side in a rear axle application. While the 30% strength reduction sounds like a major design problem, it should really be looked at from the standpoint of an perfectly symmetrical gear tooth. In this case, using the non-symmetrical tooth geometry gives a gear that is 15% stronger in the forward direction and 15% weaker in the reverse direction. While 15% one way or the other doesn't sound like a lot, its enough to make an 8" ring gear, properly cut, as strong as a 9.25" ring gear with symmetrical teeth. However, looking at it the other way of using a reverse cut gear in a rear axle, the 30% strength reduction makes an 8" ring gear only as strong as a 6" gear with normal cut teeth. One way to reduce the load on the gear is to reduce the weight of the vehicle its driving. For example, if the normal cut gear was designed for a 4000 lb. vehicle, reducing the vehicle's weight to under 3000 lbs. will reduce the load on the reverse cut gear in a rear axle to the point it may be strong enough to handle the load.Return to the top of this page]
|Gasoline||87 pump octane unleaded
(=91 research octane number)
|Engine Oil||SF/CC, 10W40||4.9 qt.|
|Manual Transmission||GL-4/5, 75W90||22R: 4.1 qt.
22RE: 3.2 qt.
|Transfer Case||GL-4/5, 75W90||1.7 qt.|
|-Dual Transfer Case||GL-4/5, 75W90||+0.7 qt.|
|Front Differential||Hypoid GL-5, 80W90||2.4 qt.|
|Rear Differential||Hypoid GL-5, 80W90||2.3 qt.|
|Power Steering||Automatic Transmission
Fluid - Dexron or Dexron-II
The 1st generation 4Runners feature a fiberglass shell over the rear seat and cargo area. This shell may be removed and installed with the following procedures. You'll need a 12mm wrench or socket for the shell bolts and a Philips screwdriver for the trim.
Refer to the fastener letter designations in the image below for the removal and installation steps below:
|Shell Fastener Designations||Cover Top Bolts:
A below, B-E above
Here are a few tips I found helpful for removing the shell:
So, you have the top off, now what do you do with it?
|A: Shell Hanger Detail||B: Shell Removal|
Here's how I remove and store my cover top (i.e. shell) in the garage.I can do this process all by myself, so no need to try and round up a neighbor or friend to come by to help.I use 4 cargp straps, not the ratchet type - those only have a limited take up length, but use the toggle-clamp style as shown in image A above. They are attached to 4 bicycle hooks screwed in the rafters of my garage. All these items came from the local hardware store.
The hooks are spaced wide enough to clear the sides of the top and far enough apart to line up with the front and rear windows. Then, I use some old aluminum roof rack bars, to which I fasten screw eyes to the ends (again parts from the local hardware store_. They are just wider than the top is, a pair of 2x4s would work, too. I slide the front window back and slide the bar though the opening. Then, I lift the top up with my shoulders and pull the straps tight on each side. This is one reason why I chose to use the open front windows for the forward support bar as there is no way (for me alone) to slide a support bar under the shell in front until it is lifted. And it is generally not possible to lift the rear of the shell first since the roof part will be pushed into the back of the cab, so this is why the front end must be lifted first (and also lowered last). And the final advantage of supporting the front of the shell with a bar through the windows is that when I have the shell lifted with my back/shoulders, it is easy to reach out the open window and take up the slack in the cargo strap.
Then in back, I lift the top up and slide the bar under the rear corner. I can reach out of the open rear window ro snug up the straps, or I can hop out and kift a corner and snug up that strap as needed. Then, its a matter of alternately lifting the ends of the cover top up and snugging up the straps until the top is against the rafters and then I simply drive out of the garage (I have to air down to 3 psi to get my 4Runner under the garage door!). To install is the reverse, back in, lower the and align the cover top, remove the bars and install the bolts. Simple, one person install and removal, no danger of dropping the top, either.[Return to the top of this page]
Driver's side fuse panel:
|15A||Rear Defogger||15A||Cigarette Lighter||10A||Stop Lamps|
|15A||Tail Lights||15A||Windshield Wiper||7.5A||Dome Light|
Engine Fuse Box:
|AM1||40 amp||Fusible Link / Gas Engine|
|- AM1||60 amp||Fusible Link / Diesel Engine|
|AM2||30 amp||Fusible Link / Gas Engine|
|- AM2||80 amp||Fusible Link / Diesel Engine|
|Head||30 amp||Headlight Relay|
|Head(RH)||10 amp||Right Hand Headlight Fuse|
|Head(LH)||10 amp||Left Hand Headlight Fuse|
|Charge||7.5 amps||Alternator Charge Fuse|
|Haz-Horn||10 amps||Hazard Light / Horn Fuse
- also Turn Signals
|Fuel Heater||?||Fuel Heater / Diesel Engine|
|Sender||Low (ohms)||High (ohms)||Sender
|Fuel Tank||110 = Empty||3 = Full||n/a|
|Oil Pressure||=||=||1/8"x28 BSP|
|Coolant Temp.||24 = Hot/239F||147 = 140F/Cold||.|
|Cold Start Injector
|Injector Resistor||2 - 3 ohms each
No10 or No20 to B+
Recently, I opened up the intake side of my engine to inspect and clean the intake. This was prompted by a peek inside the throttle body, that revealed a thick layer of black goo. Upon removing the air plenum, I noticed a liquid in the bottom of two of the intake runners. A strong smell of gasoline suggested its source, the injectors must be leaking. After removing the fuel rail, the injectors just pop out of the intake manifold. They were a bit dirty, some solvent seemed to remove the surface grime, but I suspected, after 220,000 miles of use, they may be dirty inside. So, into a box and off to R.C. Engineering they went for the standard clean, calibrate and balance service. Three days later they arrived on my doorstep looking brand new with the following calibration report:
All 4 injectors tested out at 3 ohms on my meter. Prior to service, the system balance was +/- 4.4%, afterwards 0.7% and total fuel flow increased from 67.31 to 69.95 lbs/hr, about a 4% increase, hopefully that will translate into some additional power at the wheels. All in all, a well spent $100.
Here's some related 22RE information:Return to the top of this page]
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Visitor # 583451 since 10.OCT.2001
[Last updated: 05.December.2022 ]