Hey guys I was just looking around on the 6.5L sites and I found this speedometer recalibration device on SS Diesel and was wandering if anyone here has heard of it or used it before, they say it is easy, so i am interested in getting it to fix my speedometer since the larger tires, but would like some feedback, thanks.
ssdieselsupply.com/product_274_Speedometer_Recalibration_Device.html

You do not have to buy something.All These trucks have a "DRAC" in the under dash wiring. wire harness."DIGITIAL RATIO AXLE CONTROLLER." I've seen an article on another GM Diesel web site that provides instructions to modify it your self. Some AC Delco providers that have a service dept can provide a new one for correcting tirediameter /axle ratio.I can't recall the web site ,but maybe someone will chime in with that info.

I believe my truck has a VSSB not the DRAC that the older ones have, pretty sure, but also wandering if there is something that the dealer could do that wouldn't cost as much as the speedometer recalibration devices, they are in the $150-$200 range.

IIRC the the device has more than one name. Why don't you just spring for a Heath PCM hop up.The difference in performance will thrill you.They will make the changes for the ratio, isssue.,tire size .Heath PCM is the way to maximize your power as you have the other toys in place. JMO .BTW,do you still have the CAT from your truck?.I need one to look stock on the bottom.Send me a PM about the CAT .PLS.

i just went to the dealer and they gave me one because my truck came with 35's from the showroom. So they are cant change it at the dealer without aftermarket.

I believe my truck has a VSSB not the DRAC that the older ones have, pretty sure, but also wandering if there is something that the dealer could do that wouldn't cost as much as the speedometer recalibration devices, they are in the $150-$200 range.

yes you have a drac/vssb(same thing different name), it is under your ecm, gm used it till 2001 in most trucks and if i remember right till 2005 in hd trucks

k5chris(chris darby) from pavementsucks.com is the guy that made the instructions to make your drac/vssb adjustable that is found in a few sites, tbichips.com has it

http://www.tbichips.com/drac/

Ok cool I was just looking at them online and they don't look hard to install, I was just wandering if there was a cheaper option as now I'm getting low on cash with all this Christmas shopping. Called a local speedo shop here in town and they wanted to have me pay like $350 for them to order a programer and do it so I told them where they could stick it:cookoo:.
I would like to get a programer as soon as I can afford it anyway, so I guess i'll just use the GPS for speed until I get the chip, as cruise control and ABS seem to be working fine, didn't change shift points either, it is pretty accurate until about 55 or so then by the time the speedo says your doing 70 i'm really at 75-76.

yes you have a drac/vssb(same thing different name), it is under your ecm, gm used it till 2001 in most trucks and if i remember right till 2005 in hd trucks

k5chris(chris darby) from pavementsucks.com is the guy that made the instructions to make your drac/vssb adjustable that is found in a few sites, tbichips.com has it

http://www.tbichips.com/drac/

SAAWHEEET! Thanks outaline94z71 ! I am not the original poster but that is exactly what I was hoping to find for myself later when I bought new (larger) tires or changed the gearing BRILLIANT! (love this place)

Davediesel3 i'am with you on that one...
thanx

IIRC, you can DIY. Take it out and replace the jumper with dip switches. The direction is on the site posted above.