different size tires question

[Skysm182]

(1991 Loyale 4wd) The two front tires on my subie are bald cause of bad alignment so I plan on getting the alignment fixed and two new tires. I have toyo spectrum 175/80R13 tires on the back that are in great shape and found two toyo spectrum 175/70R13 tires for $50. Will the smaller size tires in the front cause any problems? thanks in advance for responses

[El Presidente]

My GL had both those sizes on it when I got it, and it worked fine, I had the 175/80's up front and 175/70's in back. I think it looked better because it brought the back down and leveled it out. Putting smaller than stock tires on the front will change what your speedo says and putting it in 4wd isn't a good idea(especially when going fast), because the back and front will be constantly binding and if your moving fast, could get ugly. If your gonna keep it in 2wd, go for it.

[Skysm182]

I only use 4wd when there is snow on the road or its really rainy out. Is there going to be any binding issues with snow or heavy rain?

[El Presidente]

I only use 4wd when there is snow on the road or its really rainy out. Is there going to be any binding issues with snow or heavy rain?

 

yes. I just realized your rig doesn't have a part-time 4wd like my 87..I believe your problem willn't be binding, but the viscous coupler in your tranny, which with prolong binding will fail. Also if the rear is pushing the front(big tires in rear), you'll lose traction for things like steering and braking in 4wd. With big tires in the front, the car is dragging the rear tires in 4wd, which is safer, but will feel like your dragging something...because you are..When I had mis-matched tires, I only used 4wd when I was stuck.

[Skysm182]

yes. I just realized your rig doesn't have a part-time 4wd like my 87..I believe your problem willn't be binding, but the viscous coupler in your tranny, which with prolong binding will fail. Also if the rear is pushing the front(big tires in rear), you'll lose traction for things like steering and braking in 4wd. With big tires in the front, the car is dragging the rear tires in 4wd, which is safer, but will feel like your dragging something...because you are..When I had mis-matched tires, I only used 4wd when I was stuck.

 

just to clarify, I have 2wd with push button 4wd. right now with same size tires it sits higher in the back so when i get the new tires I will most likely move those to the front and have the slightly smaller ones in the rear to make it look more even.

[chad barker]

if i go with 15 or 17 inch wheels on my 87 gl wagon will it make the speedo read wrong actual speed? do u change a gear for this or what?thanks for any help

[Txakura]

http://www.miata.net/garage/tirecalc.html

[El Presidente]

if i go with 15 or 17 inch wheels on my 87 gl wagon will it make the speedo read wrong actual speed? do u change a gear for this or what?thanks for any help

 

wheel size doesn't matter, but tire size does. I don't think changing the gear is an option, but you learn to deal with it....with 30x9.5 MT's I'm going a little over 60 when my speedo says 50.

 

I like this calculator better, it a little more organized and you can sample what your speedo will read a different speeds, at the bottom of the page, instead of giving you just a percentage

 

http://www.discounttire.com/dtcs/infoTireMath.dos

[idosubaru]

+1 figure out how off you are and memorize it, you'll get used to it. they make adapters that allow you to adjust the gearing....speedo cable plugs into box, then another cable goes from box to speedo. they're a couple hundred bucks though. might as well just buy a GPS and put it on your dash.