Was just wondering if anyone has changed the speedometer gears in their 98 auto after changing to larger tires. I currently have 35's on and the speedo is around 9 miles per hr off. Someone once told me that I needed to reflash the tranny but that did not seem right to me. Let me know if I am wrong and if I am right where and what gears do I need for my current set up. I have the 3:55 ratio differentials in this truck

Thanks

 

98 should be new enough to set the pinion factor with a scan tool. I just did mine last week. I took my gps and my scan tool and kept trying combo's until I got it right.

 

Thanks:badme< I do have a gps but not a scantool. Inform me of this tool please

 

24 valves need a reflash, a 12 valve can be corrected by a new speedo gear in the transfer case.

 

thanks 1tondodge I thought that was correct> So how do I figure out what gear I need and where to look for such a thing

 

Actually 94-97 use gears, 98 and up (including 98 12 valves) need to be re-programed

 

Now I am really confused. So how do I reprogram- I do not have a scan tool- Where do I get it and how do I do it. Thanks for all the help

 

Just take the truck to the dealer, they can input the new tire size into the computer and your good to go, cost should be minimal $50-$60 and only take 20-30 mins.

 

Thanks: Will call today and see if I can get in. Will let you know teh outcome here.

 

Well the dealers here in the Forth Worth are must be hungry. I got one price of $93 and anotherprice of $157. Time to complet the job from 1 to 1 1/2 hrs. Seems a bit much for me. May just have to keep looing for some dealer that has a better price. Again thanks

 

Have you ever heard the joke about the computer connector under the steering wheel? Most say the dealer plugs it into the cash register!!!


yeah just keep checking, or if you know someone who knows someone at a shop with a scan tool offer them a 12 pack or 2 to program it