285 size tires for Suburban, Yukon

[Information Please]

My 1999 Yukon has 245's on it. I would like to go to a larger tire. I know a lot of guys that run 265's, but has anyone got any experience running the 285's. My biggest concern is whether they would rub on the fenders when cornering. Any information would be appreciated. Thanks

[AquaMan]

The 285 aspect ratio would clear the fenders, but you will raise your center of gravity tremendously and impose a dangerous situation if collision avoidance required quick manuvering. Further, your perfomance will deminsh unless you are changing the axle ratio to match the increased tire size.

However, if this is more of a show vehicle or being built strictly to "off road" then you can move to the larger tire to improve ground clearance. If this is more of the main rig for tow and travel, I would not go that large.

Handeling, performance and safty are at risk, especially with the smaller Tahoe/Yukon. The 265/70 or 75 is a moderate jump that will fill the wells nicely and maintain those items at issue above. I would recommend them before you invest in the 285.

IMHO

AquaMan~~~~~~~~~~~~~

--- "It all begins and ends at the water's edge"

[tires]

The 285 is actually the width of tread on the tire (in mm). The next number is the ratio. A 75 would mean the side wall equals 75 percent of tread width. The last number is the diameter of the rim the tire is designed for. A 285 is almost useless in snow, especially heavy wet stuff, they have to go over everything and when you hit slush etc. It will pull you around alot. Good for flotation on mud, sand etc. I think they will work on these trucks, have seen several around. I would probably stick to 265's.

[Information Please]

Thanks guys, that was some really good information I was not aware of. I thought the bigger tires would actually make the Yukon more stable. Thanks again!

[Willeye]

I owned a Yukon with the 245's on it and now I have the Z71 Tahoe. It has the 265's on it standard. It seems that I don't have the power I used to while towing. The Z71 shifts in and out of overdrive more than my Yukon did while towing. I haven't taken a long enough trip to compare the mileage while towing but I do get at least 1 mgh less with the Z71 around town. I think when it gets time to get

[Willeye]

I owned a Yukon with the 245's on it and now I have the Z71 Tahoe. It has the 265's on it standard. It seems that I don't have the power I used to while towing. The Z71 shifts in and out of overdrive more than my Yukon did while towing. I haven't taken a long enough trip to compare the mileage while towing but I do get at least 1 mgh less with the Z71 around town. I think when it gets time to get new tires I may try a size smaller if the rims will bear it.

[Starfish]

I'm pretty sure the 285 isn't actually the width, it's the width PLUS the sidewalls. That's why a 235-85-16 (or maybe it's 235-80-16) and a 265-75-16 are the same diameter tire, with different widths, but a 285-75-16 is a larger diameter (by about 3%, it turns out). I just switched from the 235's to a 285-75-16 on my F250 and they're working great. I've made four trips from Washington to Montana in the past two months visiting my ill mother, and they work fine in snow and ice. The 3% higher ratio hasn't been a problem because I have a 4.30 rear end, but I doubt if they would be a problem on most rigs unless towing really heavy.

[fordnut]

One thing you may want to check on is your warranty. Also the taller tires may affect your computers in your vehicle. there are after market chips to accommodate the size diff.

[AquaMan]

You are correct, however, a 285/70 is taller then a 265/70 by almost 2". (.75" from center.) due to the aspect calculation.

Check out these sites for a tire comparison chart that detail the tires that will work for your rig and provide some additional formulas.

(Speedometer changes) http://www.miata.net/garage/tirecalc.html
(Tire Compatibility) http://www.dsm.org/tools/tiresize.htm
(Calculations) http://www.tirerack.com/tires/tiretech/size.htm


AquaMan~~~~~~~~~~~~~

--- "It all begins and ends at the water's edge"

[Eyez]

I'd stick with the 265's. 285's would just be too much tire. That truck isn't heavy enough to get good traction on snow and gravel. I just took the 215's off my jeep, and put 235's on it. They look great, but the traction in snow isn't near as good, and since it's such a light vehicle, it squirms all over the place on gravel roads. On icy roads it handles like a camaro would, all over the place. Excellent in the mud though.


Eyez

[matt thompson]

I run B.F.Goodrich 285 at's on a three quarter ton 99 suburban and have had no problems,just slow down coming into a parking lot where there is a substantial dip or you will rub a little.Good luck, Matt

[Airwave(OH)]

I'm not sure how big a boat your towing but I always take my truck out of Overdrive when towing. I think this is recommended from the factory and have heard it can burn it up. I did have a truck burn up it's overdrive before I was told this. I guess that shifting in & out all the time is tough on em. Like I said I don't know this for sure but you might want to check into it. I know alot of guys who do this including me until it cost me a couple grand to fix.

[Bosbar]

I've had 285's on my 91 Chevy K1500 Extended Cab for about 2 years now. There was a little clearance problem on the front end so I cranked the torsion bars up all the way. To compensate the rear end, I installes a 2" lift kit. Rides a little stiff, but I figure what the #####, it's a 4 wheel drive and a truck. Had to get a 8" drop for my hitch to pull my boat. When it's loaded pulling a boat going to Canada it rides great

[Tallmike]

If you go with tires that are much bigger, you just put money in the tire dealer's pocket needlessly. On a P-metric tire the first number is the actual width of the tire in millimeters. A P235 X 75R15 is 235 mm wide and the height of the sidewall is 75% of the width, that is the aspect ratio mentioned above. I did go with slightly wider tires on my F250 supercab diesel 4X4, going from P235 X 85R16 to P265 X 75R16 tires, but in doing so the overall diameter of the wheel/tire is just about the same (if you do the calculations). If I were to have put P245 X 75R16's on the truck, I'd have gained just 10 mm in width at the expense of the truck having less ground clearance, the speedometer being off, and increased engine RPM (small) at highway speed. Take the time to have a reputable tire dealer give you an education on tires. If you live in the north where there is snow, wider tires aren't the way to go. Talk to the tire dealer about this. A tire too wide on a rainy highway or on one with black ice can have you pushing up daisies. It was ok on my truck because it has the extra weight with the diesel engine and is 4X4. It is a nice combination but I'd never go any bigger. My wife's 94 Suburban 4X2 with P235 X 75R15's actually goes better in wet snow compared to my big truck if I stay in two wheel drive. In fact, the previous truck was the same as the present truck except it was two wheel drive. I decided never again on that count without 4X4. The two wheel drive would get stuck in the grass/clay ground on the back of my place.

[ibfishn]

What it comes down to is if you want the 285's then get them. There is alot of good information being given above but one thing that has not been mentioned is tread patterns. Alot of traction problems are due to the kind of tread you have on a tire. In general (again depending on the tread) A wider tire will give you better traction on wet and ice covered roads simply because you have more tire on the road. However if you go with an aggressive tread then the opposite will be true no matter how wide the tire may be because there will be less tire in contact with the pavement. The reaso wider tires are generally not as good in snow is because they tend to push the snow in front of them instead of digging through it, but again this can be helped by choosing the correct tread pattern. Bottom line is decide what kind of driving you will mostly do and buy a tire that fits YOUR needs.

[Frank from TBay]

Good answer......Spend a little time at a reputable tire dealer and you will learn an awfull lot. Those tires that are really good in mud and snow with the aggressive patterns are very poor on ice covered slippery roads. I run 265s x75 on my 3/4 ton 4x4. Great in the snow and ice. Again this is when I need my tires the most......in the winter. If you are going with "working" tires do not go by looks alone.