ABS light after gear swap

I have a 2008 GMC Sierra with the 5.3 engine and 33 inch tall tires running the Diablo tune.

I just put 4.10 gears in my truck and started getting the ABS light.

Using my Diablo Predator u1794 running release 9r31, I cleared the code and modified the tune to account for the 4.10 gears. After about 5 minutes of driving with the modified tune the ABS light came back on. I used to see all kinds of posts about the Predator not changing gear ratio. I have that option in my Predator. However, it does not appear to be taking effect. Do I need a custom tune to fix this issue?

[06MonteSS]

lower the tire size...

2007 and 2008 abs modules have a limit on how big the tire size setting can be..

now since you changed the gear ratio, the setting is probably too big..

so lower the tire size by a half inch, and see if that solves it..

if not, lower it by another half inch, etc etc..

That appears to have worked. No ABS light on the drive to work this morning. FYI, for anyone running this setup (33 inch tall tires and 4.10 gears) I set the tuner to a 4.10 gear ratio and 25 inch tall tires. I verified with GPS on the way to work and my spedo is about 1 MPH fast at 40 MPH. IE, my spedo shows 41 and my GPS is showing 40. Close enough for me.

[06MonteSS]

cool deal..

yeah, within 1-3 mph is acceptable...

hell, I checked my wife's totally factory stock CTS once with my phone gps, and her speedo was showing about 2-2.5 mph off compared to gps, heh...

[mikel]

06MonteSS wrote:

cool deal..

yeah, within 1-3 mph is acceptable...

hell, I checked my wife's totally factory stock CTS once with my phone gps, and her speedo was showing about 2-2.5 mph off compared to gps, heh...

....again, I say user error

rofl...

[06MonteSS]

mikel wrote:

06MonteSS wrote:

cool deal..

yeah, within 1-3 mph is acceptable...

hell, I checked my wife's totally factory stock CTS once with my phone gps, and her speedo was showing about 2-2.5 mph off compared to gps, heh...

....again, I say user error

rofl...

LOL.. douchenozzle!

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