Well the old lady was out last night and got pulled over doing 51 in a 35 The cop said most of it was probably due to the bigger tires but I said it wouldn't be off much to accomodate her on her grand appearance in court. I just used 4crawlers speedo calibrator to see just how far it would be off and stock tire size is 225's and I got 31's on there now and it said almost 5mph off Does this sound right? I did tell her it was coming out of her paycheck to cover the ticket and extra insurance fees

 

Get out on a freeway, set it right at 60MPH indicated, and time it between 3 or 4 mileage markers. With a stopwatch. You need to get a good average. Write down ALL the variables, the truck tire size, time of day, freeway location, time of each leg, speed indicated, any variations in speed and why...
Then you can take it and figure out what your actual speed is (Rate * Time = Distance, so D/T=R).
And if you want to fight it, take all the paperwork into court with you. It makes you look prepared and intelligent (whatever the actuality may be *duck* Just kidding, don't hit me!), and paper always adds weight to any argument.

 

Your speedo isnt a fixed milage off, it's a percentage. Just drive down the highway like the above said. Shouldn't be that far off for 31s

 

Duuuudde!

You called your girl "...the old lady...".

You better hope that she never sees your post.

 

Measure it with GPS. Far easier than watching for a mile marker and looking at your watch while driving 60.

 

mine is off by about 5 MPH too... 80 on the odo is 75 on the GPS....

 

I just got my new tires.

when I'm going 30 it's actually 32.6.

It's a constant 2.6 mph slower than what I'm really going.

 

It will never be that far off. She was speeding plain and simple.

 

Mines off by 11.5 mph @ 65 mph. The wife got a ticket about 2 weeks after the 33's were put on ( i knew it would be off but didn't tell her and I'm not gonna now since she's already payed the fine) she no longer asks to use my rig.

 

Sounds like a plan...or I could just go to the local garage here and have it tested too...

 

Should have saw the few choice words I had when I read the email after the fact she just went to bed from being at work all night!

 

Ticket #2 coming up!

 

Oh I know she was speeding to a certain degree but I'm just curious as to how far she can fight the ticket to get possibly some knocked off of it. The cop said he would contest too to the fact that he noticed the tires were rather large...funny thing is he said he heard her coming towards him about 1/4 mile down the road

 

I suggested the freeway thing, because a) I don't have a GPS to test with and b) In this dinky little pissant town, we don't have a garage that can do a speedo test. Sad, isn't it?

 

wow man...this town is maybe 2 miles long...everybody knows everybody and everyone is kin to...well you get my picture I'll probably get the money to get a GPS when they are out of date....kinda like cassettes to cd's

 

Cassettes? You mean 8Tracks aren't "in" any more??? No WONDER I can't find any tapes...

 

I would go back and retrieve you some 8 tracks.....but I had a transfunctioner go out and now I'm stuck on welfare in this modern society with no money and rising gas costs.... Semper Fi! Tell your daughters I wish them the best of luck...

 

my speedo is off about 3mph stock because i have 225 and 4.56 gears

 

Guys listen up - Jon 7248 is correct - your speedo can never be a fixed number of mph off - it will always be a percentage. This isn't just another opinion - its fact based on the physical mechanics of how things work. If you want to avoid tickets of your own you need to understand this.

If it's off for example 5 mph at 50 mph actual that's 10%. So, it will be off 10% at any speed - 7.5 mph at 75 and 10 mph at 100.

 

Makes sense...is this anywhere in writing that maybe I can print up so she can show the court? So say 35 would be 3.5 off...if its a 10% variable?