roberttran

I am right now looking at the Michelin Cross Terrain and the Bridgestone Dueler AT Revo for my '99 LX470 in the near future. What do you guys recommend? My current tires are Michelin LTX MS. Most of the time I will be on roads, but whenever the situation arrives I will go off road.

Thanks,
Robert

Brandon@TR

If you go off road at all you should get the AT Revo's.

Bobhgd

Dunno about the Bridgestones, but I've been using the Michelin Cross Terrain SUVs for about 15k miles, so here's my comments on them:

They're quiet. Good road traction (A) and very long life rating (700 ! ).

Smooth-riding & comfy at moderate speeds, but:

They are not very good with respect to RFV (Radial Force Variation) - induced vibration at higher speeds, right around 75mph on mine.

For those not familiar with RFV: Anything in the "rolling section" of tire/wheel that produces variations in the radial force reaction of the system may induce noticeable vibrations at speed, even if the tire/wheel is perfectly balanced. RFV can also be caused by non-uniformities in the tire itself, so that a tire that appears perfectly true and balanced can STILL cause vibrations at speed. Bottom line: A higher-quality tire, with more perfectly round & true form and more uniform construction, will have less vibration at speed when properly balanced on a good wheel.

You can read some more about RFV at

http://209.176.154.132/pub/features/intro.cfm

Hunter Engineering calls RFV "Wheel Force Variation", which is probably a better way to look at it, since it includes more than just the radial-direction forces. And they address rolling section non-uniformities with the terms "uneven tread and sidewall stiffness".

Anyway, back to the Michelin Cross-Terrains: Mine are not very well-made with respect to RFV - they exhibit visible runout, and produce some vibration right around 75mph, apparently in a resonant (natural) frequency band of the overall system.

I was able to improve them somewhat by way of the Hunter GSP9700 to match-mount and then balance them, but the problem is still there.

Another post a few months ago here mentioned that he bought some Michelins and used the GSP9700 to match-mount and screen the new tires, thereby also rejecting one that was excessive with respect to RFV.

So, apparently, for all of Michelin's reputation for high quality, they are nonetheless not doing a very good job with respect to RFV on their Cross Terrain SUV tires, at least those sized for the LX470.

Next time I buy tires, I'm going to find the smoothest high speed -riding ones, and I'm going to buy from a dealer who uses a GSP9700.

BTW, feedback from the pros at The Tire Rack is welcome - I'd love to hear their comments on this whole topic.