|
|
Post by palmsprings on Nov 16, 2012 11:38:16 GMT -5
My montero sport 2001 xls 4x4 came orig w/ 255 70 x 16s
Theoretically,if you change the tire to a 265 275 285x16 ,the extra side wall height will result in noticible instability under SOME contitions due to increased flex tendencies of the sidewall.
My question is this:
just how noticible are these height increases ? The situations where this would be an issue for my wife are big side gusts of wind we get in my area. When youre doing 6omph then all of a sudden a 40 mph gust of wind from the side . My wife has been complaining for years(since it was new) about instability issues like this wind and even when theres no wind. i notice it but it doesnt bother me. Shes not a fast driver,very laidback. Since Im due for new tires i may just go back to 255s just to find out the answer.
i realize there probably arent easily accessed actual expert studies on this,so im just curious if anyone,or their wife, definately noticed a difference.
|
|
|
|
Post by monty98 on Nov 18, 2012 11:14:52 GMT -5
I've been running 33 x 10.5 x 15s for a year now, and no sway bars either, been pretty stable for me, can still take highway corners fast, maneuvering in an emergency has been no problem (as people drive like idiots here).
The difference is probably negligible.
|
|
|
|
Post by doarmihai on Nov 19, 2012 22:40:56 GMT -5
the instability that your wife talks , comes from the front end...worn out tie roads pitman arm,ball joints, idler arm...and steer gear box that has an adjustment on top ...
this is my opinion
|
|
|
|
Post by monty98 on Nov 21, 2012 18:29:14 GMT -5
I would also suggest better shocks as an option for increased stability (palmsprings, you've seen it all here!)
I think it also has a lot to do with what type of tire you get. For example I have the BFG Mud Terrains, they have 5 ply side walls (or 3 ply? I forget) and this has a lot to do with the stability of the tire when fully pressurized.
If you were to get a regular road tire the sidewalls are clearly softer and you need a lot of air pressure to make the tire stable, but at the cost of comfort.
I run my 33x105x15s at about 28-32 psi. It provides good tire stability while ensuring that there is still the added cushion from the tire.
The steering parts are still a concern though like doarmihai mentions, but they are more noticeable with shaking, vibrations, and tire wear. The steering box adjustment is definitely a must if the steering wheel feels like it is too loose or has too much movement without affecting the steering.
|
|
|
|
Post by thebe on Apr 26, 2013 15:20:02 GMT -5
One observation for the OP. In the notation 285/75/16 the 285 is the tire width in mm and the 75 is the sidewall height in % of the width. In the notation 33x10.5x16 the 33 is the overall tire diameter in inches and the 10.5 is the width of the tread in inches. Hope this helps clear up the confusion.
|
|
|
|
Post by ES_97Sport on May 3, 2013 19:46:58 GMT -5
My montero sport 2001 xls 4x4 came orig w/ 255 70 x 16s Theoretically,if you change the tire to a 265 275 285x16 ,the extra side wall height will result in noticible instability under SOME contitions due to increased flex tendencies of the sidewall. My question is this: just how noticible are these height increases ? The situations where this would be an issue for my wife are big side gusts of wind we get in my area. When youre doing 6omph then all of a sudden a 40 mph gust of wind from the side . My wife has been complaining for years(since it was new) about instability issues like this wind and even when theres no wind. i notice it but it doesnt bother me. Shes not a fast driver,very laidback. Since Im due for new tires i may just go back to 255s just to find out the answer. i realize there probably arent easily accessed actual expert studies on this,so im just curious if anyone,or their wife, definately noticed a difference. We have the same problem in CO on the front range. Broad side in 50+ Mph gusts doing 65-70 Mph on almost a weekly basis.  You're talking about a relatively minuscule difference in sidewall height between a 265 and a 285. The quick answer is unless you're using your Sport for autocross - which you shouldn't be, this is an SUV - it will make ABSOLUTELY NO difference. The problem with the '00+ models isn't tire size (sidewall height), it's suspension. My '03 Limited wallows like a hog and it's bone stock and in pristine showroom condition. My little '97 LS, on the other hand, handles like a sports car in comparison. There's almost NO difference in tire sidewall size. Shocks will not fix the problem. Shocks are NOT SPRINGS. Stiffen up the suspension. Different (higher spring rate) rear springs and tighten up the torsion bars or install new ones with a higher spring rate. Stiffer anti-sway bars. And, if you want to increase stability get new rims and move them out 1/2". And inch wider stance makes a HUGE difference. I wheel a '97 Sport that weighs in at almost 6000 gvw and sits 24" off the ground at the frame on 35x12.5x15" tires and it handles better in the corners than my '03 Limited AWD. My big Sport axles and rims, however, make it about 3" wider than stock. I'd suggest getting tires with stiffer sidewalls rather than changing sizes but I guarantee you're wife will complain. Edward www.4x4extremesports.com |
|
