Tire Question...

[Gerritt]

Quick question fellas..

 

I put on my winter tires.... only on the rear as the rubber on one set is still in decent shape so I put them up front... (I will be getting another 2 winter tires for the front in short order...)

 

But here is my issue.. I have 6 factory rims for my truck.. 4 with all seasons, and 2 with winter tires mounted..

 

I put the winter tires on the rear.. 235/70/R16

 

and moved the current tires that were on the rear to the front which were 255/70/16's

 

While I liked the look of the truck with the bigger tires... I only have one set on the front... and the rear tires look awful small back there in comparison to the fronts.. LOL.... the truck does not seem to be level any more...

 

Is my gas mileage affected having bigger tires up front/mismatched tires?

 

Ford suggests the 235/70/R16's...

 

But my non winter tires are larger... They were that way when I purchased the truck (Larger Tires)

 

am I doing myself a dis-service in terms of $$$ (petrol) by keeping a larger tire/mismatched tire?

Edited October 26, 2008 by Gerritt

[misfish]

G

The slimmer the tire the better. Cuts through the snow easier . I learned this from an old swede. He was right. It only took me 30 yrs to realize it.

After all.the summer is meant to look good.LOL

[misfish]

Oh I should add. I never mix match my tires. Run the four out,and get another four after that. Makes a BIG dif when you want to break and have control.

[John Bacon]

I assume that you have a two wheel drive truck. Do not engage four wheel drive with different size tires on the truck!

 

I am not sure what the effect of larger wheels on the front will be for a two wheel drive vehicle. Your headlights may need to be re-aimed for the benefit of on coming drivers.

[Gerritt]

JB... Yes my truck is two wheel Drive..

 

G

[BillM]

I was going to say, your diff will be hating you if you have 4wd

 

You might have an issue with the front tires getting 'ontop' of the slush/snow instead of cutting through the the rears will...

[HTHM]

Bite the bullet go to the wreckers and buy two more rims, and have matching winter tires put on.

[jediangler]

Do yourself a favour and match up the fronts with the same snowtires. People forget that the snow tires on the drive wheels only gets you going better, but without snows on all four, your braking distance increases significantly. Stopping is as important, if not more, than getting going in the snow and ice.

[Wild]

Gerritt the shorter the tire the higher the engine will turn, great for acceleration, lousy for highway economy, still if that is the tire size that originally came new on the truck and no gear changes have been made then you should get close to the factory MPG rating.

 

But by mismatching tire size especially taller tires on the front you are compromising the safety of the truck by changing the suspension geometry and braking characteristics. Even worse if you load the truck up you now have an unstable and unsafe vehicle which would not pass a vehicle safety inspection.

[Bernie]

Some good advise here from the guys Gerritt. A big wide tire is great on dry pavement for traction and turning but as soon as you add water or snow/ice it becomes a different equation. A wide tire becomes essentially a snowshoe in these conditions. You want your tire to contact the road surface as much as possible, hydroplaning is not a good thing here . As Brian has mentioned a narrower tire increases the pounds per square inch at the contact patch. It also allows the moisture to escape out from under the tire faster.

Stick with the factory tire size, especially the diameter. Vehicle gear ratios are usually set up to match power output/fuel economy/speedometer. It's not always the case but it is in most circumstance.

Snow tires can be dangerous when only put on in pairs. They can give drivers a false sense of driving conditions. For example on a rear drive vehicle it will give you better acceleration but most braking takes place on the front of vehicles due to the forward weight transfer. Front drive vehicles are especially dangerous when snows are only put on the front. Most of the vehicles weight is forward with engine and trans sitting there. This already gives it much more traction. So if the rear tires are not sticking to the road due to poor traction when a turn or braking is necessary the rear can swing out causing lack of control. Believe me, I have witnessed it happen more than once as well as seen the results arrive in my shop.

I try not to sell tires as to me they are a Pain in the but have come to realize they are one of the most overlooked safety item on a vehicle.

Edited October 27, 2008 by Bernie

[Greencoachdog]

(I will be getting another 2 winter tires for the front in short order...)

 

Define short order... you should probably take your winter tires back off until you have 4 matching winter tires! A mismatched set of four isn't good!

[Fisherman]

Something it also may affect is the ABS, different size tires, computer reads different wheel speeds and can activate the ABS when not needed.

[Gerritt]

Thanks for all your input fellas.. I will be looking at a new set of winters... Thanks!