So Ive decided to change the tires on my car from the stock size in the back of 215/65R15 to a 255/60R15 and leave the front at stock size. I was wondering if going up in width by that much will cause rubbing on the inner fender wells if im using the stock rims on the car. Also wondering if the stock rims will even hold a tire of that width or should I go and get new rims? I am keeping the stock size tires on the front of 215/65R15.

I noticed when I bought the car that the driver side of the car was sitting about 2 inches lower than the passenger side on the rear. I replaced the coil springs in the back because the ones that was on it were worn out. the heavy duty springs gave the driver side the lift needed to even the ride out and not let it sit crooked. After a few months, I got to noticing that the car is starting to settle back down on the drivers side again. Could the shocks be the cause of the lowering on that side now or could it possibly be the spring seats possibly being worn out?

 

1. 255/60 will change your tire diameter, and with it, your speedometer/odometer... For a 60% ratio, the size should be 235 wide... For a 255mm wide tire, should use a 55% aspect ratio (255/55/15) to keep the speedo within limits (stock diameter is 26" and you should try to keep within 1/2" of that).
2. Check the spring seats (the rubber mounts at the top of the springs) for wear and replace as necessary. May need to get some decent springs as well as it sounds like you got some cheap ones if they're worn out THAT fast. Do you make a lot of left turns? Also, when you go to replace the spring seats/springs, unbolt the shocks at the top and see if they compress easily by hand AND return... If they compress by hand very easily and do NOT rebound, they're junk...

 

I did some calculations on the tires and converted everything from mm to inches. the 255/60R15's will only give me about 1/2 inch raise in the back. Will that throw the speedo of too much or just by 1 or 2 mph?

Springs that I bought were MOOG heavy duty variables instead of standard. I dont know if that is a decent brand or not but thats whats on it now. The turns vary depending on where I have to go, but they stay pretty consistant and even.

 

Funny, I ran my calculator twice and still get 27" diameter... 255mm x 60% (or .60) = 153mm / 25.4mm per in = 6.02" section height x 2 sections per diameter = 12.04" tire height + 15" rim diameter = 27.04" ... Stick with the 255/55's...

Moog is a good brand, but I think any number of them are made in China now... However, it could be that the spring seats are shot or maybe the spring on the driver's side has aligned with the insulator properly (there is a notch that the end of the top coil is supposed to rest against)... Also check the shocks as I suggested while you're under there if you're worried about those. Chances are, if those are the original shocks, they're deader than dead by now (I know mine were!).

 

Yeah I wasn't thinking about the tires being 1/2" bigger on each side. That definitely will throw the speedo off by more than just 1 or 2 mph. Thanks for the tip. Now the only question is, will the extra inch or so in width still sit on the stock rims and not collapse on me from the weight of the car and the rims sitting an inch more toward the inside of the tire?

With the shocks, like I said, they looked new. I'll double check the seats for the springs because that's one thing I never thought about checking when I replaced the springs. I should've replaced the seats and the shocks when I replaced the springs but money was tight at the time. Know of a decent brand of shocks that will give me the performance I need for everyday driving and cornering?

 

Not sure on the tire width... I had 235's on the car when I bought it and they seemed to work fine, but the 255's are an inch and a half wider (40mm is just over an inch and a half, 25.4mm per inch) than stock 215/65's... Maybe ask in the Suspension forum...

Check the spring seating and then the shocks... Monroe shocks will probably get you what you're looking for unless you really want to shell out for KYB's everyday shocks...