top speed

[dave p]

what is the highest miles per hour any one has gone with the 2001 and 2002 hd trucks with allision 5 speed automatic? i have hit 100. at what speed does the chip slow you down? dave p

[NutNbutGMC]

^..I'd say you have topped out. Gouge on it and see. Why stop at 100 mph? But just beware and keep an eye out in your rearview mirror. Don't sweat the cops, watch out for the mini-vans that can smoke a Duramax any day of the week. Even the 4-cylinders. :mad: :mad:

Mine tops at 97 MPH. D@mn those mini-vans. Two passed me today. :mad: :mad: :mad:

[SoMnDMAX]

With the 285's, I top out at about 105 MPH, figuring in the approximately 8.5% speedometer error.

[tmg115]

can't you change your speedo to the tire size you have?

[SoMnDMAX]

The speedo is not adjustable, due to GM's reluctance to release the proper programming code. :mad:

[JB 2500HD CC]

Is that for all tires sizes??? I put 265's on my truck and the dealer fixed my speedo....

[SoMnDMAX]

JB, don't bet on it. your dealer most likely changed the ABS settings, which has no effect what so ever on the speedo.

Seems that there is some fudge factor built into the trucks, as most seem to come within less than 2% when you install 265's. So, that means the speedo was "fast" from the factory. My truck is right on with the 265's, as verified on a Mustang dyno last December.

[chane]

I have been close to the 120 mark on my Escalade Gauges w/the help of my HPIII.