My truck has 35" tires and the speedo is off by about 5mph so my fuel mileage isn't right on the overhead readout. Anybody have any cheap fixes for this? The local speedo shop wants around $300 to calibrate my truck... seems expensive. Any ideas??

 

You wouldnt take it to a speedo shop. Find your tires on the manufacturers website, look at the specs, find out how many revs/mile and take that number to your dealer and have them flash it in. Its a simple deal and wont cost $300. Some dealers will do this for free. (but i wouldnt count on it)

 

Hmm, my dealer offered to do it for free. I just haven't got around to it in two years.

After buying a $50K truck from them I think they can spare 5 minutes and get your speedo in sync with your new sneakers.

 

Cost me $35.00 at a Dodge Dealer.

By my calculator..your speedo is off 8.5%...if your truck came with 265's.....which will put you "off 5 mph"..only at 60 mph.
It will be off 12% if it came with 245's!

RJ

 

but it will increas his waranty by the same 8.5 %

 

Unfortunately, the warranty is already gone and the closest dealer wants $82.00 to flash the computer. Guess I will have to spend the dough because I can't stand the speedo being off. Thanks for the advice.

 

I would wait for a trip inland...or make a trip inland, to a small town, country dealer...middle of the week...mid afternoon. It's only a 5 min job.
$82.00 seems outrageous.
JMO...it's your money!

Rj

 

Summit Racing has a device that you can adjust yourself.It installs in the speedo speed signal from the ABS computer,this is the source of the speed signal to all devices that use a speed signal.It just changes the count,I like it cause I can adjust the shift points using this device.

 

I would think that costs more than $80 bucks though

 

Dealer wanted to charge me 90 bucks to enable the cold weather idle.

I threw a fit and said it is a 5 minute procedure, and no way am I going to pay for an hour of shop time.
They cut it in half, but was a low as they would go.

I got the Truespeed way back when no Dealer tech knew how to change the tire size to anything bigger than 265's, and yes, it was a bit more than $80 bucks, around $200 I think.


phox