dodgedude361

I brought my truck to the deaLER TO HAVE THEM RE CALIBRATE THE SPEDOMETER (sry for the caps lock) for my new 315's. They said the tech couldn't find the right adjustment, the list didn't go up to 315's.

Can someone tell me what to say to them, i want this done right.

Thx in advance

cheff

Tell them you want to calibrate your speedometer to 606 revolutions. That got me to with in .5 reading at 65 compared with my GPS. Some say go with 601 but I did the math and 606 revolutions is what I came up with. At 601 the speedo was still off by more than a mile. That is for the 315 I had on my '02 1500. I have not calibrated the speedo for the 33" tires I am running on this truck. When I do I will let you all know what I came up with.

Good luck.

dodgedude361

Well, i just got off of the phone with them , and they say" Our NEW computer does not have the option for your tires....sorry sir"

Just makes me crazy

RamWheelsBy4

I cant remember the exact menu sequence that the DRBIII goes through. Use the search, there is a post somewhere with the exact sequence to be used on the DRBIII.

Once they get to the "Pinion Factor" ( I think this was in the ABS sub menu), I believe they select the "other" option and enter the Revs Per Mile. Cant remember for sure but I think this was done with up/down arrow type button to increase or decrease to correct number. I used 605, my calculations said 605.3 for my 315s and it is very close to exact. I have used GPS at mph and measured 50 mile straight stretches.

Find another Dealer!

hognutz

It is the pinion factor they need to adjust. Call a different dealer as yours is most likely stupid.


When I took mine in the guy looks at me and say "nothing I can do for you" I am like what do you mean? you just need to set the pinion fator to 577? He say's " I think that is out of range" I said okay "what is the range" he say's "I am not sure"

short story long they take the truck in and set it to 577. He almost sent me away though. If I was not stuborn and made them check what the range was they would have turned me away out of ignorance.

cheff

I had 2 dealers say that same thing. I really think they just don’t know how to do it. But it can be done. Go to another dealer and when they fix your issue, go tell this dealer what you think of them, and where you are buying your next truck.

MedicShawn

Yeah it's the pinon factor. These are the directions J Body sent me;

Hello, hope this isn't too late. Under the ABS go into
"misc", there you can go into "set pinion factor", it
will then show you the correct tire size and axle for
your vehicle. It will ask you if you want to change,
go with yes. I didn't go past that point today, but I
believe it will then want you to change the number of
tone ring teeth in the drb. You'll have to adjust that
number. I believe if you max it out it will be close,
if not you'll have to get a GPS, have someone shadow
drive you, or use a stop watch to get it close. Hope
this helps..

I used 601 and my speedometer reads a couple of MPH fast at 60. Hope this helps.

Mark Thomas

They have that box you can plug in and it re calibrates your speedo, I'm not sure who make it but I think JEGS sells it. Someone chime in if you know the name of this product.

bigblock2stroke

Its definitely the ABS module and it is done with the DRB. I find it hard to believe that no one knows how to use it. I did it on my 99 and I had never used the DRB before.

MR4WLR

Superlift has one but it's like $250
Superlift TruSpeed Speed Signal Calibrator pn33002http://www.superlift.com/

Cheapest I found on a quick search is $178.01
http://www.truckcustomizers.com/prod...4SPL413.5.html

phox_mulder

I have the Superlift Truespeed.

I would only recommend it for those who change tire sizes more often than a women changes her mind.

It has two positions, both adjustable, for say summer tires and winter tires.

If you had the Dealer do it each change, the $$ would add up and make it worth it.

Otherwise, just get it done at the Dealer.

Hindsight being 20/20, I wish I would have, but this was over 2 years ago, and the Dealer techs really had no idea how to do it.


phox

JHardwick

What math? Can you tell me your calculations?

cheff

Ok, ok my math is not that good I am looking for the website I used to figure it out. It had tons of calculators on it for just about anything you wanted. I been to busy to look, but when I find it I will post.

On the specs for the BFG 315's they say 601 revs per mile, thats on their website. I think anywhere between 601 and 609 you will be ok. Now the trick is finding a dealer that knows what they are doing.

RamWheelsBy4

Try this tire size calculator.

http://www.1010tires.com/TireSizeCalculator.asp

mike1080

I had the same issue when I got my 33" tire. The dealers programmer only goes to a 265 or 285 size tires. The service manager was nice enought to figure out a setting in the general area. He set the spedo to 620 for my 33" Parnella Jones tires, the calculation per the web site is about 611 rev per mile. I figured it was close enough. The web site is http://patriot.net/~jonroq/Tech/Txrjtires1a.txt .
Hope this helps or gets you close.

P.S. - i also found out a 33" bfg has a different dia. of a 33" parnella jones, might try calling the tire manf, for the rev per mile .