Freightliner Speed Limitation

[sweetbillebob]

We are in our third Freightliner. All three truck's speedometers have not been accurate. In this truck we are going 62 when the speedometer says we are going 65. I have also run two checks on the odometer in this truck, I need to run one more just to be sure. The odometer says we have traveled 1025 miles when we have only traveled 1000. The point is, that when/if we limit, we will be limited at less than 65 if an adjustment in the "tire rev's per mile" is not also changed. I have run a 20, and 50 mile check, comparing mile markers with odometer and GPS. I plan to run a 100 mile check so I know how much to change "tire rev's per mile" before getting the limiter set. Changing the "tire rev's per mile" can be done at the same time the limiter is set, probably for no extra charge since most charge for 1 hour min.

 

[piper1]

This is getting to be very common as the tread on new drive tires keeps getting deeper. Some tires now come with a full inch (32 32nds) of tread and you can loose almost 4 mph by the time they wear out.

When you get your ECM set, I used to put in a rev number that was used for a steer tire of the same size and brand. EG, if I had low pro 22.5 Michelin XDN2 (511) drives I would use the number for an XZA3 steer (518).

You need to keep a couple of things in mind, 1) if you are in a state that writes tickets for 1 MPH over the limit you need to remember at first you are going a tad faster than the speedo. 2) IF the MTO is smart enough, they MIGHT check to see if your rev's match the brand of tire. That might get tricky.

 

[nightcreacher]

the speed on your gps is perfect,forget your speedometer.