Good day all,
I am new to this forum and as of 2009, new to Ford.
My wife inherited a dandy speeding ticket the other day for doing 145 km in a 90. She is quite upset over the ticket and assures me, and everyone else she was only doing 105-110. So today she visited a tire shop and was told that if the wrong size tires were installed on the truck,, this would affect the speed.
If she was indeed, doing 110 (on speedometer) and the Police assured her the radar was correct, there is a huge discrepancy of 35km. Has anyone else heard of this???
Any ideas??
The truck is a 09 F150 XLT with 18" tires.

BTW, luv the truck!!!

 

A couple of questions first. 1- what are the factory sized tires? 2- What are the new tire sized at? 35 km is what 22 mph difference? That would have to be like about a 20-25 % shift from the factory. So are your tires 20-25% bigger then factory?

 

Sorry, the tires are factory P275/65/18, came with the truck when purchased new.

 

1. Look at your door sticker, it should list the tire pressure and the stock tires or go to http://services.forddirect.fordvehic...=YOUR_VIN_HERE and see what the window sticker lists.
2. Go look at your tires
3. Go here U.S And Metric Tire Size Information Calculator and enter the window sticker tire information and the currently installed tire information. It will show you the speed discrepancy.

Just between you and me - there is no way the tires will cause that much of a difference. Me thinks the better half was hauling a$$...

 

Check the sticker on the driver's door jamb. If it has the same size tire listed, there is just about zero possibility that the speedo is off by that much. (The only reason the sticker would differ is if the dealer did a wheel/tire swap before you bought the truck.) Even if the dealer swapped on some larger diameter tires, it's unlikely they'd be more than 5-10% off.

You could check your speedo in a number of ways. In the old days, I would go exactly 60 mph on the freeway (in the US) and time exactly 60 seconds between mile markers. Likewise, if I could go 10 or 20 miles and have the odometer tell me that I went 10 or 20 miles, I'd know that the odo was correctly calibrated and could pretty well assume the speedo was on as well. (If I went 10 miles per the mile markers and my odo said I only went 9 miles, likely the calibration was off.)

GPS units will tell you actual speed and you could check with one of those if you have access. Or have a friend drive alongside you in his/her car/truck at a certain speed and confirm your own speedo.

My guess is that your wife's foot is just a *bit* heavier than she is willing to admit, but the cop's radar gun could have either been miscalibrated or could have been reading a different vehicle going faster than your wife was.

Good luck,
George

 

Thanks for the advice, will check into it this week.
As for the heavy foot, well the stars aren't aligned enough for me to suggest that and the couch is not that comfy!!!!!!!

 

I didn't suggest that you needed to make this case to your wife. Check out the truck. If the speedo readings are clearly off, you can try to substantiate this in court for your wife.

If the speedo seems accurate, your wife can go to court and discuss her side of the story with the judge and if it were my wife, I would be as supportive as possible. It always pays to go to court; if the cop does not show up, you can get let off. Sometimes the judge will cut a break, etc... If her driving record is in danger, get an attorney; radar can sometimes be challenged successfully.

Good luck,
George

 

+1 on going to court, especially if it involves points. I took my last 2 speeding tickets to court as they were with points, and the officer was willing to negotiate removing the points and consequently lowering the fine. Just be very humble and apologetic in dealing with the officer, most of them are pretty cool and will work with you. Good luck.

 

These trucks ride so smooth and are so quiet, that even my wife has told be that she has caught herself speeding and not realized it.

Was your wife talking on the phone? Had she just passed a slower vehicle on a 2 lane?
Was she late for work, or getting home? Sometimes the speed just gets away from people. And if there was a problem with the speedo, you would have been stopped by now as well. A 35 kph error in a speedo is very easy to detect. When you are in traffic, your blazing by everyone else. I don't know about the great white north, but in several states, the judge can no longer dismiss points. He can reduce fine, but the points stay as it is an administrative action by MVD.

 

Not in PA, at least not yet. I was just in court over the summer, 40 in a 25- where the 25 meets the 40. Apparently you can't be doing 40 until you get to the sign... Even at 4:25 AM and NOBODY else on the road. But I kept my cool and it paid off when I met him at the courthouse.

 

get a lawyer and have it reduced.

 

I'd consider that a last resort. How much will a lawyer cost? Might not be too cost-effective

 

Was your wife talking on the phone? No
Had she just passed a slower vehicle on a 2 lane? Yes
Was she late for work, or getting home? No
A BMW car had just flew by her, wife was going about 110kms, then went to pass another car, just after the BMW flew by her. The police said they clocked the BMW at 138 and my wife at 145.
We noticed in the brochure for the truck is set to a standard 17, and we have 18 wheels. But the sticker on the doors says 18.

 

Of course the wheels have nothing to do with tire diameter. 275/65/18 are the stock tire.
That being said, I upgraded to 275/70/18's and my speedometer is off a couple mph at 70. Nothing as drastic as you're suggesting.