Category Archives: 4×4 Tech

How to fix, maintain or modify your off road adventure truck is here. We also discuss gear and how it holds up out on an adventure.

Lexus GX470 gravel guard


Lexus GX470 owner's manual

Changing the front differential oil on your Toyota truck is an easy maintenance activity! Although there is not a lot of room to work, we have a couple tricks that will make changing the gear oil in your FJ Cruiser, 4Runner or GX470’s front differential much simpler.

Let’s start with what you’ll need:

Before you begin, fill a buck with about 8″ of hot water and set your gear oil containers in the hot water. This will heat up the oil and allow it to flow more easily.

To get to the front differential you will need to remove the factory gravel guard. Remove the four bolts holding the OEM gravel guard to the frame and set aside. This is a good time to look everything over and check for any leaks or damage that may exist.

lexus GX470 front differential fill plug

Using the 10mm hex socket remove the fill plug. Why the fill plug? This ensures the fill plug isn’t stuck and you’re left with an empty differential case and no way to fill it.

Now using the 10mm hex socket, remove the drain plug and allow all the gear oil to drain into the catch pan.

lexus GX470 front differential drain plug

Once all the differential oil is drained, reinstall the drain plug using a new gasket. The Toyota specifications call for 48 ft/lbs of torque to ensure the plug and gasket are seated correctly and wont come loose on the trail.

Filling the front differential can be tough. There is very little room so I recommend the top down funnel method. Grab a funnel and attach about 2 – 3′ length of hose (I find clear aquarium hose works great) to the end of the funnel. Feed the hose down the through the engine compartment and place the end of the hose into the fill opening.

The gear oil that has been sitting in the hot water should now flow easily down the funnel, through the tube and into your front differential. Your owner’s manual will specify how much oil is required. You can verify you’ve reached full when the gear oil just begins to spill out of the fill hole.

lexus GX470 engine compartment

Using a new gasket, tight the fill plug to 29 ft/lbs, wipe down any gear oil and reattach the factory gravel guard.

Maintaining the front differential of your Toyota FJ Cruiser, 4Runner, Prado or Lexus GX470 is easy and the care you give it will go a long way to ensuring your 4WD continues to operate correctly on all your overland adventures.

Don’t forget to also change the rear differential oil.

Lexus GX470 Rear differential Oil change

This step by step procedure for changing the gear oil in your rear differential works for a Lexus GX470, FJ Cruiser, 4Runner and most modern Toyota trucks.

The gear oil in your truck keeps friction to a minimum and ensures the long life of your differential gears.  Proper maintenance by changing the differential oil is simple and keeps your off-road truck working as designed and saves money. Changing the differential oil yourself allows you to learn a little more about your overland vehicle (you never know when hat knowledge will come in handy on the trail).

The first big decision is what oil to use. It is important to consult your owners manual. Toyota lists the quantity, type and viscosity of oil required. For our 2008 Lexus GX470 the manual lists:

  • Capacity: 3.3 quarts
  • Type: Hypoid gear oil APL GL-5
  • Viscosity: SAE 80w-90

Other item to pick up before you start include new drain and fill plug gaskets.  Unless your on the trail working a field repair, don’t try save a few pennies by reusing these little items.  (Get a complete set of differential and transfer case gaskets they will also fit your FJ Cruiser and 4Runner)

Most back yard mechanics will have the tools required to perform this simple activity.  The tools you will need include:

Start by placing your GX470 on flat level ground to ensure good draining and proper refill. Tip: clean the axle housing with soapy water and a scrub brush to remove the road and trail gunk.  This will prevent any dirt from falling in to the differential while changing the oil.

Remove the fill plug using a 24mm socket . The fill plug located in the middle(ish) of the rear axle housing.  By removing the fill plug first the housing you ensure you can refill the differential before draining all the oil out.

With the oil catch pan in place remove the drain plug, located on the bottom of the rear axle housing, using a 24mm socket. If your going to use gloves, this is the time to wear them.

The drain plug has a magnetic insert designed to attract and hold tiny metal shavings that become suspended in the oil.  Yes these are little bits of your gears.  Inspect the drain plug checking for any chunks and observe how much has accumulated.  This will give you an idea of what has been going on inside your differential.

toyota cleaned differential drain and fill plugs

While the oil completely drains, grab the shop rags and clean the fill and drain plugs, removing all the gunk and accumulated metal shavings.  When your done the plugs should be clean and dry.  Don’t forget which is which.

After the oil is fully drained, wipe the area clean and re-insert the drain plug with a new gasket and hand tighten. Remember the drain plug has the magnetic insert. Now set your torque wrench and tighten down the drain plug.  Toyota states the torque specifications for both the drain and fill plugs as 36 foot pounds for our 2008 Lexus GX470. This torque setting is the same for the Toyota FJ Cruiser and 4Runner.

Remember that funnel with flexible tube?  Getting the oil out of the bottle or can and into the axle housing through that little hole can be tricky.  One of the advantages of the Hopkins FloTool 10704 Spill Saver Measu-Funnel is that the flexible tube funnel cap will screw directly on to some quart bottles. Another tip is to place the unopened gear oil containers in some hot water for five to ten minutes. This will warm up the thick gear lube and allow it to flow more easily.

Squeezing out three plus quarts of thick 90 weight through the tube and into the axle housing will take awhile so get comfortable. 

toyota fj cruiser rear differential fluid level

Checking the fill level on flat ground is easy.  The oil should barely begin to run out or just about to run out (within 5mm of the fill opening).

Hand tighten the fill plug and new gasket followed by torquing down the plug to Toyota specifications.

Wipe down the housing and check for leaks. Drive around the block a couple of times and check for drips when the test drive is complete.

Like all trucks your Toyota or Lexus requires the differential oil to be changed in order to keep the gears turning smoothly.  Changing the rear differential oil on a GX470 (or FJ Cruiser, or 4Runner) is a simple maintenance job anyone can do with a little know how and about 60 minutes.

Improved Lexut GX470 rear doot strut connect

Improved Lexus GX470 Rear Door Gas Strut Modification

The other day, Hula Betty, in her most sportive, I get to work on her truck, but she wants this fixed now voice,  announced it was time for me to replace the clunky Lexus GX470 rear door stopper with a gas assisted strut that will allow the door to glide open, stay open and easily close.

A common complaint about the Lexus GX470 and Toyota Prado 120 is their rear door stopper mechanism’s poor design.  Even in a slight breeze the rear door becomes randomly self-closing if you forget to lock it open.  And opening the door with an arm full of gear can be overly challenging on an angle.  Changing out the original door stopper mechanism with a gas strut solves both problems as well as adding a smooth glide on opening or closing the door.

Changing out the Lexus GX470 or Toyota Prado 120’s OEM door stopper with a gas strut and door reinforcement plate is a simple mod that anyone can perform in no time at all.

You will need a couple of tools:

  • Felt tip marker
  • Flat head screw driver
  • 10mm box wrench
  • 12mm box wrench
  • Small grinder
  • Electric drill
  • 5/16″ drill bit

The parts required are:

Step 1 -Using a flat head screwdriver, pry off the little round cap covering the bolt holding the OEM door stopper to rear frame of your Lexus GX470.

Step 2 – Remove the  old clunky door stopper mechanism.  Start with the bolt you just exposed on the bumper.  Then remove the two bolts on the underside of the rear door.  To avoid scratches, support the door stopper with one hand while you remove the bolts with the other.Improved Lexut GX470 rear doot strut bracket bolts

Step 3 – Remove the long thin plastic cover over the gap between the truck and the bumper.  The Lexus GX470 has a portal on the cover for sliding in the jack handle to lower the spare tire.  If you remove that little portal cover you can get a better grip to remove the long cover running the length of the bumper body gap.

Step 4 –  After the cover is removed you will see the bracket that the old door stopper mechanism on your Lexus GX470 or Toyota Prado 120 attached to.  Using a 10mm wrench, start by removing the bolt on the bracket that is attached to the bumper.

Step 5 – A 12mm wrench will remove the two bolts holding the bracket to the back of the truck frame.Improved Lexut GX470 rear doot strut cut

Step 6 – With a cutting disk attached to a small grinder, cut away the portion of the bracket that the OEM door stopper slide onto.  This is just above the point at which the threads begin.  After completing your cut, smooth down any high points and rough edges with a grinding disk.

Step 7 – Throw a little rattle-can paint on the bracket to keep everything looking good and prevent rust from developing.

Step 8 – To fabricate a rear door reinforcement plate you will use the OEM door stopper as a template.  Place the door stopper on the aluminum flat bar arranging as if the flat bar was the rear door and the door stopper would be attaching to it.  Trace the edges and bolt holes onto the flat bar with a marker.Improved Lexut GX470 rear doot strut flat bar

Step 9 – Cut the aluminum flat bar along the traced lines using  your small grinder with a cutting disk.

Step 10 – Drill out the two holes for the bolts to pass through.  Notice that one of the bolt holes is a bit elongated to allow for slit adjustments.

Step 11 – Sand  or grind down any rough burrs or sharp edges.  If you want a professional look,  lightly sand the entire flat bar to give it a brushed finish.

Improved Lexut GX470 rear doot strut flat barYou are now ready to assemble everything back together.

Step 12 – Reattach the bracket to the back of your Lexus GX470 with the three OEM bolts you removed.

Step 13 – Press the plastic bumper gap cover back into place. Don’t forget to put the spare tire portal cover in place as well.Improved Lexut GX470 rear doot strut flat bar

Step 14 – Screw one of the 10mm ball studs into the bracket you just attached.

Step 15 – Mount the door reinforcement plate you fabricated to the underside of your Lexus GX470’s rear door using one of the OEM bolts that held the door stopper in place and the second 10mm ball stud.  The 10mm ball stud should mount into the original recessed nut hole on the underside of the door furthest away from the bumper.  The OEM bolt screws into the original recessed nut hole closest to the bumper on the underside of the rear door.

Step 16 – Snap the gas strut onto the  10mm ball stud at the bumper first then to the 10mm ball stud on the rear door.Improved Lexut GX470 rear doot strut connect

Step 17- Give everything a good tug to ensure it’s securely attached and your ready to test your new, smooth gliding Lexus GX470 rear door.

Note: Since your Lexus GX470 rear door will open and close tens of thousands of times, get in the habit of touching the door lightly and slowing it just before it fully opens in order to avoid any stress build up over time on the strut.

If you find yourself down under you can get a really cool complete rear door strut kit for the Pardo 120.

And in case you were curious, Hula Betty loves this mod!

Lexus GX470 Battery Replacement

Battery replacement tool listOwn a overland truck long enough and you will need to replace the battery. In this article we use our Lexus GX470 as the demo truck but the same procedures will work for all vehicles, although access to the battery will be different.

The trend these days is for truck manufacturers to value esthetics over function under the hood.  Engine bays with plastic covers look great but that sleek, clean look costs time (translate to dollars at a dealership or local garage) when it comes to working under the hood.

On a Lexus GX470 about half of your time will be spent removing the front plastic engine cover in order to gain full access to your truck’s battery.

The plastic cover retainer clips (buttons) are intended to be reusable. Be prepared to replace several plastic retainer clips.  I find that many dealership technicians are focused on speed often at the expense of broken retainer clips.  Reusing damaged clips may save you a few dollars but this is the start of the down hill slide to those little rattles that drive me nuts.  I always keep a handful of various retainer clips around knowing it is a small price to pay for peace and quiet.broken Toyota retainer clips

The steps to replacing the battery in a Lexus GX470 are easy:

    1. Remove the 12 (or so) retainer clips on the front plastic engine (radiator) cover.  These retainers release their grip by sliding a flat head screwdriver in the channel then gently lift the button head of the retainer.
    2. Remove the 2 retainers that hold the front plastic cover to the power steering cover, located toward the front on the passenger side of your Lexus GX470.  These retainers will release their grip by pressing down on the center button with a screw driver.Lexus power steering cover retainer
    3. Lift the positive lead cap (usually marked with “+” sign) from the battery terminal (some will tell you to remove the negative ground first).  A 10mm socket will quickly loosen the clamp. Carefully lift the wire lead and tuck the wire lead out of the way ensuring it does not fall back onto the battery’s terminal.
    4. Remove the negative lead cap (referred to as the ground and usually marked with a “-” sign) and lead wire from the battery terminal. Tuck the lead out of the way.Toyota retainer clip removal
    5. The battery hold-down comes off next.  A 10mm deep socket will loosening the nuts.  The rear hold-down hook should have a clip holding the ground wire (it did when it came from the factory) that will need to be unhooked.
    6. Carefully lift the battery out of your truck.  Use care not to strain yourself, the battery is heavy and GX470 front engine cover removal
    7. This is a good time to clean out the area of any dirt and debris.  Check the tray for cracks and replace if needed, before setting the new battery into place.
    8. Attach the battery hold-down.  The shorter of the two hook rods attaches in the rear.  Remember to re-clip the ground wire to the hold-down rod.
    9.  Before connecting the battery, smear a thin coat of no corrode gel (available at most parts stores) on the battery terminal and slide on anti-corrosion fiber washers.battery hold down position
    10. Connect your leads to the battery terminal.  Avoid touching your tool against both terminals or other metal on the truck.
    11. Make sure to fully tighten the wire lead connection to the terminals.  Lose connections can cause corrosion and hard to find electrical issues down the road. Reattach the terminal lead battery terminal gel
    12. With the battery securely connected, set the front plastic engine cover back into place and secure it with plastic retainers.  To avoid breaking retainer clips, ensure the button is lifted allowing the bottom prongs to come together.  You may want to gently press the prongs together so they easily slide through the lined up holes.  Press down on the button top gently locking the retain into place.
    13. Don’t for get the two retainers holding the front cover to the power steering cover.  For these retainers pull the center pin up allowing the retainer to slide in, then press it back down flush with the button top to secure it in place.

Your Lexus GX470 or other overland truck should start right up.  But you will notice your clock needs to be reset.  You will also need to reset the driver’s remote window controls console.


lexus GX470 window console

How To Reset Lexus GX470 Remote Window Controls

lexus gx470 rear passanger windowIf you have had reason to disconnect or replace the battery on your Lexus GX470, you probably found that the drive’s remote window console controls on the door no longer work for the passenger or rear windows.  Luckily there is an easy fix.

  1. Turn the key to the on position
  2. At the remote window press and hold down the window button until the window is completely down.  Continue to hold the button down for two (2) GX470 rear window control
  3. Remaining at the remote window’s control button, lift the window button and hold it up until the window is fully up.  Continue to hold the button up for two (2) seconds.
  4. Repeat steps 2 and 3 at all the other windows.

Test that your remote window control console on the driver’s door.  The remote console has re-learned it’s role and can now fully operate all the remote windows.  If any of the remote window controls don’t work, go to that window and repeat steps 2 and 3.

This window console reset will also work on most Toyota, Lexus, Honda or Acura vehicles with similar remote window controls.

automatic tire inflator close up

I H8 To Air Up – How To Build An Automatic Tire Inflator

tire inflation in the coldWe love the soft, rock gripping ride you get when you air down big E rated, 10 ply off-road tires.  Hate is not too strong a word when we have to inflate the tires back up. We often argue about who’s turn it is to sit next to a tire while our little compressor pumps its brains out to re-inflate the rubber up to highway pressure.

An air tank will make quick work of re-inflating tires but it doesn’t really work for trips like our Baja overland adventure where we were constantly adjusting our tires’ PSI up and down as we moved between asphalt, desert sand, boulder filled dry riverbeds, muddy swamps and beaches.

We knew there had to be answer… it just took eight years of scouring the Internet and talking to other overlander travelers to figure it out!

We decided to build our own automatic tire infator using an adjustable in-line air regulator??!!  What is this tire inflator voodoo witchcraft you ask? Add a common air tool inline regulator that lets you set the desired PSI to a tire inflator, hook it up your air compressor and walk away.  The regulator will stop the air flow automatically when the tire’s PSI reaches the preset level.

This project took some experimenting before finding what worked best for us.  The key is to start by selecting your regulator, then build your parts list off of the port sizes available on your regulator.

NPT references the national pipe thread taper (aka  American standard pipe), refers to the size of a connector and the size of the thread on any connector.  The thread size is especially important, because non-standard fittings may not provide a full seal, and will allow air to escape from your hose lines and connectors.

A note on hoses before we get started. The hoses with built-in chucks that we tried seemed to come with flimsy chucks that we managed to break in the field, which is why the recommendation below is to purchase a separate hose and separate locking brass chuck.automatic tire inflator parts

What you need (or at lease what worked for us):

To start, attach the brass male quick release plug to the input (or intake) side of the regulator.

To the output side (which is all other ports) of the regulator attach your hose. Attach your brass lock-on air chuck to the end of your whip hose.

Note: to prevent air leaks at the joints, you want to use a little Teflon tape or Permatex 59235 Pst Pipe Sealant on the threads prior to connecting everything.

If you plan to use a gauge, attach it now to an open port on your regulator.

Now following the regulator’s direction, set your regulator to the desired PSI.  Depending on the regulator this may take a little trial and error.

With everything assembled, connect your automatic tire inflator to your compressor and test it out on your spare tire to make sure it is stopping at the desired PSI.

That is it!!

Instead of sitting next to each tire for up to 10 minutes, we can now attach our auto-fill tire inflator to our pump, connect the locking chuck to the valve stem, start the compressor and move on to other important things, like checking for trail damage, repacking our recovery kit, changing out of our trail boots, posting a picture to Instagram or just grabbing a soda and sitting in the shade. Gone are the days of sitting next to a tire, up to our ankles in mud while the rain pours down, holding a tire inflator and watching the tire gauge.

automatic tire inflator in actionAn additional benefit of this regulated automatic tire inflator is that all four tires are at the exact same PSI when it stops.  No more back and forth to reset pressure all around.

Will this little device change our life…  probably not… but it will free up time to get repacked and ensure we are ready to go when our last tire is aired back up.

If you don’t want to DIY it…  how about the Longacre 50581 Auto-Fill Tire Inflator / Deflator.  Longacre Racing does offer an automatic tire inflator… But there is one down side.  We found the chuck that attaches to the tire’s valve stem leaves a lot to be desired.   The word “cheap crap” comes to mind.  Rather than return the inflator (it had been 6 months and a few uses) we went on to Amazon where we picked up a high quality hose for the 1/8″ port they used (Interstate Pneumatics TW100 12 Inch Gray Hose Whip for Inflator) and tire chuck (Coilhose Pneumatics CH15A Open Lock-On Chuck, 1/4-Inch FPT).  Easy swap and together they make this a good tire accessory.  But it added $18 (+ shipping and taxes) to the overall cost.

install lexus gx470 rear bumper

Installing Lexus GX470 Swing-Out Bumper

lexus gx470 rear swing-out bumperSo you may have noticed some Lexus GX470 discussions from us here and out in the forums…   Yes we did it, we added a Lexus GX470 to the fleet.  Just not this one.

Why you ask?  It’s built on the same J120 Toyota Prado Land Cruiser platform as our FJ Cruiser but with four doors, a bit more room, a whole lot more luxury and a V8 engine.  Our new Lexus GX470, affectionately named (by Hula Betty) Fat Girl, will be primarily used for overland adventures and as a daily driver for Hula Betty.  She wont get the massive mods we have on the Blue Bunny but she will be getting some upgrades to her suspension and armor.

While Fat Girl will remain stock for now, that doesn’t mean we haven’t started to consider options.  One option is the Metal Tech 4×4 rear swing-out bumper known as the Pegasus.  Mark over at Metal Tech 4×4 put all their Toyota Land Cruiser experience into creating this bumper.  No cutting, no welding, this swing-out bumper fits right into the design of the Lexus GX470 and allows you to carry larger spare tire, fuel cans and your Hi-Lift jack.

And when it comes to installation…  Well see for yourself.  We put together an installation video to help folks install their Metal Tech 4×4 swing-out bumper on the Lexus GX470 and give us an excuse to get an up close look at the Pegasus.

If you just want the highlights about this bumper than give this introduction video a look.  It walks you through some of the key features of this overland bumper.

What do you think?

fried eggs in skillet

Overland Chef… Huevos Ranchero

One of my favorite times during a overland adventure is early morning.  Sun rising over camp, quiet in the air, warm coffee and anything is possible.  And I get to cook breakfast!  I love to cook.

My all time go to favorite camp breakfast, huevos ranchero. Hearty, probably not that healthy but oh so very tasty.  Let face it, really anything with chorizo and eggs is going to come out good and can’t really be screwed up…  although there was the “chorizo surprise” debacle a few years back.

The secret to this breakfast delight is in the chorizo…  It can’t be that farmstead, grass-fed, dry-aged, loin-based, hand-rubbed, hipster chorizo.  No, this has to be the chorizo of my people, true Mexican chorizo, made from grinding up pork salivary glands, lymph nodes and fat with spices that cooks down to delicious, spicy, coagulated, crimson oily paste.

huevos ranchero ingredientsIf you’re looking for an exact recipe, give Betty Crocker a call.  I roll pretty loose… This is it:

  • Get the stove going… and keep the heat on the low side as you cook down the chorizo in a heavy skillet.  Keep it moving, don’t let it burn.
  • After a few minutes, add a handful of chopped onions and continue to cook (and stir) until the onions take on a translucent state.
  • Next add a minced garlic clove, giving a few more stirs.
  • Toss in a bunch of chopped cilantro and mix it in.
  • Pull the mix to the sides of the skillet making room to cook the eggs. (fry or scramble the way you like)
  • When the eggs are ready, remove from the heat and sprinkle everything with grated cheese.  Any good Cheddar, Jack, Queso Fresco, Queso Anejo, Cotija, Oaxaca, Panela, Asadero will do. Cheese is its own food group in my mind.

Serve on a plate, wrapped in a flower tortilla, over a corn tostada shell and drizzle a little hot sauce over everything.

This is really just the base.  You can add in fried potatoes, poblano or anaheim peppers, or diced tomatoes to make the huevos rancheros your own.

FJ Cruiser hood work light

Let there be work light

FLOOD-IT pro LED under truck lightingAround the shop or in camp, light is always at a premium.  We always seem to have to work on parts that are tucked into a dark corner of the truck or start prepping camp meals as the sun is dipping below the horizon.  Until now the solution was head lamps, flashlights or old fashion trouble light.  These light sources are good but they don’t always provide enough light or put it where you want it.

Enter the FLOOD-IT pro LED rechargeable light.  This small but powerful free standing flood light has found it’s way into our kit.  So what makes it better than all the other 10w LED lights out there?

  • Compact free standing base with a handle that is easy to grab.
  • Magnetic feet.  Set the light on the ground, stick it to the hood, attach it to the truck frame.  This work light makes it easy to stage the unit so it illuminates where you need.
  • Cordless and rechargeable, lasting up to four hours. The work light comes with an AC adapter and a car charger making it easy to recharge in the shop or while driving to the next camp.
  • IP65 water and dust protection with a wide 120 degree beam spread.

For us its the compact size, rechargeablility and magnetic feet that make this work light a winner.  When on the trail the light sits magneticly tight on the rear floor where we can quickly grab it. In camp we stick it high on the truck and point the light right where we need it most, at the camp kitchen, and cooler.

The FLOOD-IT pro LED light is now a part of our off-road kit and a favorite around the shop.  Check out Red Kitty Industries for this and other rechargeable work lights.

man talking on CB radio

Cobra 75 wx st CB Radio Install

Installing a CB Radio in a Toyota FJ Cruiser is an easy do it yourself project.  Several years back we installed a Cobra 75 wt CB radio in our truck.  Unfortunately back then we didn’t take the time to create a how to video.  So when Voodoo Brad asked us to help him install his CB radio we jumped at the chance.

If you follow our step by step instruction for installing a Cobra 75 wt CB radio in a Toyota FJ Cruiser you will need a few other components to install a complete CB system.  Below is the parts list we have used on both our Toyota FJ Cruiser CB radio installs:

  • Cobra 75 wt CB Radio
  • Firestik MU8R18 18′ EZ-Install CB Coaxial Cable
  • Firestik II 4′ fiberglass CB antenna
  • All Pro Bandi Mount
  • Firestik K1A CB Antenna Quick Disconnect
  • Firestik K4R CB Antenna Stud Mount
  • Firestik SS3H CB Antenna Spring Heavy Duty
  • SWR meter

And if you need help Tuning Your CB Radio we have help for that.

It really is this easy to install a CB yourself and have professional results.