New to me 07 Sport 3 GT handling question

[Luap]

I recently bought a used 07 mazda3 sport GT with 48k on it.

I have a handling question. The car has 17 inch wheels with 45 series Yokohama tires on it and seems to me the car has some bizarre handling characteristics. Over uneven pavement it can get a bit squirrelly in the back end. Like it wants to jump sideways if the rear suspension gets a sudden whack from bad pavement. Everything else about the car seems great but this one aspect.

At first I thought perhaps I just wasn’t used to the relatively firm ride with those low profile tires but after living with it for a couple of weeks I’m concluding it doesn’t really feel normal. It caught me by surprise on a bad patch of 401 the first week we had it and I almost overcorrected it into the next lane when the back end jumped loose.

Anyone have any ideas as to what the problem could be?

[Cardinal Fang]

Have you had the alignment checked?

[Fobio]

A few things I'd check before taking the car in:

1. Rear tire pressure.
2. Rear shocks. Check to see if there's any stain/fluid leaking.

These two are things you can check on your driveway/garage before taking it in for alignment or dealer service. ALL street cars are tuned from factory to have a stable backend, especially during NORMAL driving. Your tail-happy car is definitely not normal. Keep us posted as to how it goes.

[MajesticBlueNTO]

...check for an aftermarket rear sway bar as well.

[maplephin]

as to Fobio's comment, definitely look at the rear shock and see if it looks wet or shiny. When the shocks blow and you hit a small bump, the backend will definitely feel like it is kind of jumping or moving around.

[Luap]

Thanks much for the suggestions guys. Some answers so far:

Alignment not checked yet. Only had the car a week or so but will do.

No add-on anti-sway bar

Shocks look stock and no leaks detected -- at least by sticking my head under. Might need to pull wheels off to get a real good look. I'm kind of shocked they could go bad so soon.

Tire pressure was high. The door jamb sticker suggests 32 psi and they were all close to 40 as delivered by the dealer. I've let them down to 32 and, while there is the tinniest improvement, I have to admit the problem is still mostly there.


One thing I did notice is that the rear wheels have enough negative camber to be noticeable. Not huge, but definitely there when viewing the car from the rear. Is this normal for a stock 3 GT? No doubt I'm getting used to the handling but I find it hard to believe a stock setup would be so twitchy.

[Luap]

Two other items. I notice that the vibrations after a smack to the rear suspension seem to reverberate through the car for an unusually long time. I can feel the shuddering throughout the steering wheel a good few seconds after the bump.

I've also driven behind the car and watched the action of the rear wheels while on the highway and they seem to be bouncing more than I'd expect. Almost a continuous series of little, jittery hops after hitting a bump.

Looks and feels for all the world like super high mileage shocks gone bad...just a mystery why this at only 50K...?

[Donutz]

Negative camber is normal for these cars (well hatches for sure; I can't speak about sedans). Based on your description from driving behind the car and the continous bouncing, my gut says the shocks are done. It could be something loose as well, but shocks would be the obvious starting point.

When the car is parked, try bouncing the car continuously by pushing down on the rear (like dribbling a b ball). If the shocks are really far gone, you can usually get some extra cycles out of them fairly easily by doing this.

[JashiK]

aren't stock tires 50 series and not 45?

[Donutz]

^ Yep, I believe that is correct.

[Luap]

Hmmm - that tire size reveleation is interesting. Just went out to double-check and can conirm the following make and size: Yokohama Avid W4S 215/45/R17.

Assuming 215 is the stock width I guess the result of the previous owner swapping in 45s is that my speedo, and perhaps my indicated mileage and fuel consumption are all slightly out of whack?

And could the 45s result in a suspension, wheel, and tire combo that induces these rear end jitters?

(I also have bounced the car by hand at the rear and it certainly doesn't seem to feel like the shocks have gone floppy.)

[Donutz]

I think fuel mileage and speedo are very mildly affected by 45's. I ran them for a about 2 summers on my stock wheels and I don't think there was much difference compared to 50's. I don't think it's the tire size that is causing the funny handling. Are all wheels tight? Was the car ever in an accident?

[Mty Mous]

Hmmm - that tire size reveleation is interesting. Just went out to double-check and can conirm the following make and size: Yokohama Avid W4S 215/45/R17.

Assuming 215 is the stock width I guess the result of the previous owner swapping in 45s is that my speedo, and perhaps my indicated mileage and fuel consumption are all slightly out of whack?

And could the 45s result in a suspension, wheel, and tire combo that induces these rear end jitters?

(I also have bounced the car by hand at the rear and it certainly doesn't seem to feel like the shocks have gone floppy.)


I believe my '07 GT Sedan's stock tires are 205\50R17, so I'd say 215\45R17 sounds good, you're only 0.45" or 11.5mm shorter than stock height (in overall diameter).

[SpeedBaby]

one thing that comes to mind: there's a chance that this car has been previously lowered and the stock suspension was put back before the trade in (im assuming by the age of the car that it was a trade in?). In this case there's a chance that whoever was putting the stock springs back on, might have installed them incorrectly (twisted, angled) and this is causing the handling issue. Usually, however, this would cause some sort of clunking coming from that area... Either way best thing to do is to jack up the car and have the rear suspension inspected

[Luap]

I bought the car from an out of town Ford dealer who accepted it as a trade for a new truck from the original owner. I ran one of those background checks (not carfax, the other one -- can't remember the name). Only one previous owner confirmed, always Ontario registered and got no hits from national insurance registers on accident claims.

The Ford dealer, not surprisingly, couldn't answer many of my questions about the specifics of the car, trim levels, etc. but they were terrific on other customer service items.

After I took delivery, I noticed two tears in the rear bumper, one on each side starting down where the mud flaps would mount. The mounting points had torn out on either side and the tears were starting to come around the side of the car.

When contacted, the dealer expressed shock and dismay (although I don't know how anyone with the car on a lift checking brakes for the safety would miss such a thing) but immediately agreed to pay the full tab for fixing it. I got a new OEM rear bumper painted and installed through my local Mazda dealer at no cost. The invoice total they picked up was over $800. It was the right thing to do but nevertheless I was amazed at how quickly the Ford dealer got on it for me.

Anyway, I digress. I did ask if the car had been lowered becuase it didn't look to me totally stock. They said no it hadn't and I didn't even consider it was incorrect tires. I also didn't think of the good point made by Speedbaby that perhaps it once was lowered and was hastily put back close to stock as possible for the trade in.

Here's a question. I found the previous owner's name on the warranty card. Would you folks take it as an invasion of your privacy if you were called up out of the blue about a car you used to own? I could get some more answers about the history I'm thinking.

And one final note. I did ask the body shop to have a close look behind the bumper for damage that might have been caused as a result of whatever ripped the original bumper. Nothing to report they said. Obviously it suffered some kind of impact but there were no collision marks or paint cracks on the bumper anywhere other than those tears. It's as if maybe something got caught under the bumper and pulled backwards until it popped at the mounts or something or the car drove forward with something snagging the bumper.

There is a very, very shallow dent you can only see from certain angles above and behind the rear left wheel but I don't see how that would have affected the bumper or the suspension. Again, no paint damage there.

Curiouser and curiouser...but it is looking like a complete go-over by a real Mazda dealer is probably in order.

One other idea....I don't know if any of you are in the Mississauga or Oakville area but perhaps I could take someone for a test ride to demonstrate. Just an idea.

And sorry for the long post!

[Luap]

OK - sorry to dig this up from the dead zone but I wanted to close the loop on this as it were.

My local Mazda dealer has diagnosed the handling problems as being due to struts gone bad. How or why they can't say.

The struts will be replaced under warranty as part of my 48,000 Km service.

When I get the car back tomorrow I'll fling it around a bit to confirm they actually got the problem.

My thanks to those who took the time to reply to my original concerns on this.


Post Script to my dealer visit. They said my engine splash shield was broken due to a road strike and kindly offered to replace it for the princely sum of...$250 installed...:whoa.

I see the rape and pillage continues as far as Mazda OEM parts prices go... I'd be obliged if someone can suggest an alternative source for this $15 piece of stamped plastic.

[Zoom Zoom Boy]

OK - sorry to dig this up from the dead zone but I wanted to close the loop on this as it were.

My local Mazda dealer has diagnosed the handling problems as being due to struts gone bad. How or why they can't say.

The struts will be replaced under warranty as part of my 48,000 Km service.

When I get the car back tomorrow I'll fling it around a bit to confirm they actually got the problem.

My thanks to those who took the time to reply to my original concerns on this.


Post Script to my dealer visit. They said my engine splash shield was broken due to a road strike and kindly offered to replace it for the princely sum of...$250 installed...:whoa.

I see the rape and pillage continues as far as Mazda OEM parts prices go... I'd be obliged if someone can suggest an alternative source for this $15 piece of stamped plastic.

The part is like $30-$40.00. The rest of the price is labour. Send a PM to Joe, FLIPDADY on here who is the parts manager at MOT. Then take it to Jimmy at Street Performance to install it for you. If it costs you even half of what you were quoted, I would be surprised.

[Rob23]

get you suspension check i had a serious problem with my front driver side strut was like totally shot. it was fine untill you hit uneven pavment or a bump on a turn or accelerating, then the car felt like it was going to jump to one side.