2004 Highlander - Off Road Experience

[pcaker]

We had recently an interesting off road experience in our '04 V6 4WD Highlander, which I have recounted in detail in the attached file.

In summary, the Highlander performed amazingly well, particularly producing great and reliable traction on steep loose slippery surfaces. The suspension rode and soaked up the bumps impressively. The body felt tight and rattle free. Biggest issue was the vulnerability of the exposed engine and transmission sumps although they do have about 9" ground clearance, and the weakness of the low slung plastic fuel tank which is down to 6.5" clearance - probably the greatest problem. A further lesser issue was the vulnerability of the sidewalls of the passenger vehicle style P radial tires. Lastly, the rear suspension rod links are quite thin although they have good ground clearance. I understand that there have been problems with the links getting bent from the impact of large flying stones, however I have so far avoided this problem.

[bepperb]

Pictures sure would be cool. I've enjoyed the HL's "soft road" capabilities on dirt roads/logging trails/urban offroad adventures, but never anything like what you have enjoyed. So do the GoodYear TripleTreads get a thumbs up?

[pcaker]

Yes, the GoodYear Fortera TripleTreds gripped that trail pretty well. However, it was dry and rocky - no mud. I suspect that more aggressive all terrain tires or GoodYear's own Wrangler Silent Armor would be much better in mud. I was quite worried about damaging the Fortera sidewalls, and we did suffer one minor gouge which fortunately did not reach the cords.

In fact, following our recent great off road experience, I am considering a moderate off road upgrade. Of course in an ideal world, I would pay what it takes to get a Land Cruiser or 4Runner, but our Highlander has a lot of life left in it and money IS a consideration. Also, we will only be back roading occasionally, so its not as if the vehicle is going to be pounded on a daily basis.

The current scheme under consideration is:

1. Fit Goodyear Wrangler Silent Armor LT225/75 R16 10ply tires onto std Highlander steel rims. I estimate that this will raise the vehicle about 1/2", and the tires will be much stronger and more suitable for off road. They also have full winter rating. I am fairly confident that fender clearance will be okay. I looked at a range of taller sizes, and this one seems the most realistic fit and provides most of the benefits wanted. I suspect that speedo and odometer will change from running fast to being more accurate.
2. Fit spacers 1 1/4" height between suspension strut top metal/rubber mount and top of turret, front and rear. This will require threading the solid aluminum cylindrical spacers (probably 1 1/8 to 1 1/4" dia.) to act as a coupler for now extended top of turret 3 mounting studs. This will push down the top of the struts and provide a further lift of 1 1/4" for a total of 1-3/4".
3. Check the alignment.
4. Fit 1/4" aluminum guard plate under engine and transmission sumps ending just forward of engine sump drain plug to facilitate oil changes
5. Fit 3/16" aluminum guard plate under fuel tank in place of existing very weak thin metal guard. Both guard plates wil slope up at the front and be as solidly attached to frame or floor as I can manage.
6. Add aluminum thick walled tube cut longitudinally and epoxied around rear suspension lower link for increased impact resistance.
7. I believe that the vehicle handling and ride, which is currently so good, will not be adversely impacted too much by the above described modifications, except perhaps by the harder tires.

These modifications will not create a tackle anything off road vehicle, but should enable the Highlander to tackle the kind of tracks which I described previously, with much more confidence. Frankly, I would like to drive that same route again one day, and others like it, without so much risk and worry!