I'd confidently say the Terra Grapplers are some of the most confidence-inspiring tires for off-roading on the market outside of dedicated MTs. I took my 4Runner anywhere I could and through mud, sand, snow and rock, they tires never let me down. Even though I had passenger-range tires, I never had a puncture, even after having limbs stuffed between the rim and tire (they kept their bead too when this happened!).

On-road traction
The Terra Grapplers provide more dry grip than any AT tire I have ever used and made my 4Runner feel nearly sporty in day-to-day driving. Before I had the Terra Grapplers on my 4Runner, the tires were the weak point in cornering performance with my Icon coilovers up front and Old Man Emu springs/shocks in the rear. The previous tires would scream and howl on on-ramps and didn't like being pushed hard. The Terra Grapplers provided an amazing level of grip and allowed the truck to handle like it was meant to with the suspension upgrades.

Wet weather performance
The factory siping in the Terra Grapplers helped them cut through wet streets with no problems at all. Even after 25,000 miles, the tires had no problems in the rain and the traction control on my V8-powered 4Runner would only kick in when I was a little too heavy with the gas pedal.

Snow/ice performance
I'll preface this part of the review by saying I had never driven in snow until I purchased these tires. Growing up in San Antonio, Texas, there weren't many opportunities to drive in winter conditions. The main reason I bought the 4Runner was due to the snow in Pennsylvania and combined with the Terra Grapplers, I never felt unsafe. The tires provided great traction in deep snow and over thick ice for the first 20,000 miles. Once the tires wore some, their snow traction decreased, but I never felt unsafe. I did try some dedicated snow Nokians and felt they were a step up from the Terra Grapplers. With that being said, if you only had room for one set of tires for your truck and had to deal with snow, the Nittos would definetly be a good choice.

Comfort and treadlife
The Terra Grapplers are a sportier AT tire, so my 4Runner didn't get smoother, but they don't beat you up either. They are quiet for an AT tire and didn't get louder with age, so that was a plus. I will say treadlife is the one point of angst for owners of these tires. Some people just can't it that these tires only last for 30k miles, but I felt the tradeoff was worth it since they provided so much grip on and off road. Sure there are tires that will last longer and there are tires that provide just as much grip, but the Terra Grapplers offer a lot of pluses for the money and are a good compromise for those who need a tire that will take them anywhere.

• Soldering iron

• Solder

• Wire strippers

• Wire cutters

• Electrical tape or heat shrink

• Flat head screw driver

• Socket wrench with a 6 inch extension, an 8 mm socket and a 10 mm socket

Necessary Parts:

• Head unit
  

• Wiring harness

• DIN kit for your truck (make sure the color matches)

• Pioneer 7900BT head unit, purchased used for $150
• Metra wiring harness, purchased new for $10
• Metra dash kit, purchased new for $22
  

Prepare the harness

1. Use a wire stripper to expose about a ½ inch of cooper on each wire from your new head unit’s wiring harness and the aftermarket wiring harness you bought to plug into your Tacoma’s factory wiring. An automatic wire stripper works great and can be picked up for $10 from RadioShack. I used a Metra wiring harness that I picked up from my local car audio shop, but they are all roughly the same. Here’s the wiring diagram:
   
   

   • Red - 12 volt ignition / accessory

   • Yellow-12 volt battery / memory (the primary power cable)

   • Black - Ground

   • Blue -Power antenna / amp turn on

   • Orange white - Dimmer

   • Gray - Right, front +

   • Gray/black- Right, front -

   • White - Left, front +

   • White/black - Left, front +

   • Violet - Right, rear +

   • Violet/black - Right, rear -

   • Green-Left, rear +

   • Green/Black-Left, rear-
     
     

     

2. To solder the wires together, cross the exposed wires (one from the head unit’s harness and the matching one from the aftermarket harness) in an ‘X’ and twist them together.
   
   

   

   
   

3. Plug in your soldering iron and allow it to heat up. Some suggest wrapping the tip in solder before plugging it in since the solder helps conduct heat better. Once the soldering iron is at operating temperature, place the wires on the tip of the soldering iron. In about 30-45 seconds, the wire should be hot enough to melt the solder. Put the solder on the wire (not the tip) and allow it to be absorbed into the wire. You don’t want to put the solder on the tip of the soldering iron.
   
   

4. Finish soldering all of the wires together and tightly wrap them in electrical tape. Do this for each wire you are connecting.
   
   

5. Use zip ties to bind the wires together as shown in the above photo. This will allow for better air flow behind the head unit.

Remove the factory head unit

1. Remove the climate controls from your truck by gently prying it loose using a flat-head screwdriver wrapped in one layer of electrical tape or a putty knife. Remember to be gentle; you don’t want to brake the clips holding it on. Once the climate controls are loose, unhook the wire harnesses and put it away somewhere safe.
   
   

   

   
   

2. Remove the 4 10mm bolts that directly behind the climate controls. You’ll need a 6 inch extension to do this.
   
   

   

   
   

3. Once the bolts are removed, you can now remove the head unit. Pull up and out and it should pop out easily. Remove the wiring harness (there are three) and the antenna wire. Also, remove the harness for the hazard lights and airbag unit.
   
   

   

   
   

4. You'll now have a big empty hole where your head unit used to be.  Go inside and get ready to put your new head unit today.
   
   

5. Remove the 4 8mm bolts that hold the factory brackets on to the head unit and save these for later. You’ll want to use a socket since the metal is soft and is easily stripped with a screwdriver.
   
   

   

   
   
   

   
   

6. This is where things get interesting. To remove the hazard button/airbag light, you’ll want to gently pry it out of the factory head unit. To do this from the back of the unit and try to locate the 4 clips (one on each side) that are holding it in place. Take your time and use the photos above as a guide.
   

7. Once you have removed the hazard button/airbag light, you’ll want to install the head unit into your aftermarket dash kit. Your dash kit should have instructions for this part of the install process.
   
   

8. Once you have your dash kit together, you can go ahead and install the head unit. Just follow the directions in reverse for removing it and remember to take your time to ensure everything is aligned properly. A few important notes:
   
   

   • Plug the harnesses (there are two for Tacomas ) into the radio and turn on your car before finishing the install. This will give you the opportunity to test the head unit before you get everything together again.

   • With the Metra kit, you have to insert a grommet into the dash of your Tacoma that will allow you to screw the radio housing into it. I found it best to tighten the screw most of the way and to then test fit the trim panel to ensure everything was aligned correctly.