Depends on what brand and type the highway tires are. Go over to tirerack.com or a similar website - they have ratings and customer reviews on nearly every current model of tire. See what they say about your tires in the type of weather and driving you'll expect to encounter this winter.

On my '05 Jeep Liberty 4X4, OEM tires were Goodyear Wrangler S/T's in 255/75/16. Those things were damn near worthless even on dry pavement. A tall narrow minivan tire - on a 4000 lb SUV! On tirerack, Wrangler S/T's were rated as unsatisfactory or poor in every category by people that had used them - I didn't see a single positive review. Every time I went around a curve at even close to the recommended posted speed for the curve, that Jeep felt like it was on the verge of tipping over. The Wranglers had zero traction on wet pavement - 4 years ago a woman in a Lincoln Navigator pulled out 4 car lengths in front of me, trying to do a left hand turn, saw me coming, and sinmply froze and stopped in the middle of my lane. Even at only 35 mph, on a wet street, that Jeep slid along like a pig on roller skates, ABS chattering like mad, because those Wranglers didn't have any grip, and I went into her left front quarter panel square on. Better than 2 grand worth of repairs to my front end.

After that, I switched to Cooper Discoverer ATR's 245/70/16. Same overall diameter, and pumped up to 40 psi, haven't affected highway MPG enough to notice (but then, I have the CRD diesel version). Beast also feels much more stable with wider tires on it. Been quite satisfied with Coopers - on both of my vehicles and all of my parent's vehicles.

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Just say "NO" to Ethanol - Drive Diesel

Mitchell Oates
Mooresville, NC
'87 300D 212K miles
'87 300D 151K miles - R.I.P. 12/08
'05 Jeep Liberty CRD 67K miles
Grumpy Old Diesel Owners Club