ABS problems with tires over 34"

McRat

Diesel Hotrodder
Aug 2, 2006
11,249
26
38
64
Norco CA
www.mcratracing.com
Even if you calibrate the speedo for larger tires, the ABS does not know you've changed it, and it might throw ABS codes.

You need a Tech2. Plug in, select truck, go to chassis>abs>tire size:

Use 245/70-19.5 for 33" tires
245/75-19.5 for 34-35"
235/80-22.5 for 36-37"
9.0-22.5 for 38" and up.

Tires over 44"? Sucks to be you. No calibration that high. Reduce speedo correction until it works right.
 

$Smokin_Duradog$

New member
Sep 16, 2006
209
0
0
43
Goshen, IN
I have 38 tires the speedo is correct now with EFI Live but I have the abs problem. So all we have to put in 9.0- 22.5 in Tech 2 and that will solve this problem? Thanks for the info :)
 

Lennart

Not from here !
Aug 10, 2006
305
0
16
Detmold, Germany
What is the ABS problem with taller tires? On my truck I have the problem that the rear will lock up waaaay to soon and when the ABS kicks in it will also reduce performance of the front brakes.
Can the front-rear proportioning be fixed this way?
 

Trippin

SoCal Diesel
Aug 10, 2006
663
2
0
Just an FYI,

I've had two LBZ trucks in the last week with 35" and 37" tires, both with 4.56 gears. I changed the gear ratio in the tune to 4.56, selected the proper revs/mile based on the tire size "only" and then selected 285-75-16 for the ABS controller.

Logging the front wheel speed sensor vs the rear showed this to be the correct settings.

When I tried using the larger settings in the ABS controller the speed sensors showed a huge difference, perhaps because of the gears.


Hope this helps.

Guy
 

1slow01Z71

Wannabe EFILive Tuner
Im sure this is a dumb questions but if I get my truck flashed with the tech2 for my 35s then swap back to my stockers for some playing around on the streets is it going to mess things up again? Just didnt know if having a smaller tire then what the ABS computer thinks Im running would cause the same problem since alot of computers run off lower limit values.
 

2wd_Sled_Puller

Heavy Equiment mechanic
Feb 19, 2008
1,356
0
0
Florida
Im sure this is a dumb questions but if I get my truck flashed with the tech2 for my 35s then swap back to my stockers for some playing around on the streets is it going to mess things up again? Just didnt know if having a smaller tire then what the ABS computer thinks Im running would cause the same problem since alot of computers run off lower limit values.

IIRC the brakes will lock up way sooner and be more touchy
 

1slow01Z71

Wannabe EFILive Tuner
With my 35s its already a scary ride if I have to slam on the brakes. Ive only done it once, the sun was in my eyes and couldnt see the red stop light, finally saw it, slammed on the brakes, rear tires locked up and sent me sliding sideways.:eek: Guess Im going to swap back to the stockers for a while dont really feel like killing someone over something like that since Im not going to be able to get to the dealer for a while.:(
 

WTF

slow and broke
Nov 20, 2006
229
0
0
Wasco,CA
see i havent had any trouble like that and i run 35's and 36's but my truck is at the dealer all the time and they could of done it for me
 

captnduramax

New member
Dec 16, 2006
181
0
0
las vegas
when towing ... and of course I have 1 of those hot lly's...it sends an abs alarm on the dash and after i restart a couple times it goes away. Funny thing is that no codes when I check it with Efi Live. Only when it overheats on a grade.. never heard of such a thing


Capt
 

Got Boost?

New member
Jun 20, 2008
35
0
0
Vegas
do I need to take my truck to the dealer to get this done? I have 38" tires with 4.56 gears and and until I found this sight, I had given up a few years ago about having the abs/brake light come on since getting regeared.
 

LBZrcks

.........
Jun 2, 2007
5,297
12
38
38
SoCal
do I need to take my truck to the dealer to get this done? I have 38" tires with 4.56 gears and and until I found this sight, I had given up a few years ago about having the abs/brake light come on since getting regeared.

Anyone that has a TechII can do it for you, maybe Chad or one of the Vegas folk up there have access to one
 

The Neens

BFD
Staff member
Aug 10, 2006
4,596
1
36
Monrovia, Ca.
I've had two LBZ trucks in the last week with 35" and 37" tires, both with 4.56 gears. I changed the gear ratio in the tune to 4.56, selected the proper revs/mile based on the tire size "only" and then selected 285-75-16 for the ABS controller.

I spoke with Guy about this today because I'm having trouble adjusting this on my '07 and a friend's '08...Worked just fine on our '02...Anyone else had any luck with a '07 or newer?
 

kodiak

New member
Sep 25, 2007
178
0
0
Any chance of getting my speedometer to read anywhere close??? I have tried the tire size.....revs per mile....everything. But the speedo still reads 13 MPH off. Eg. 60MPH is actually 73MPH. Efi techs, are supposedly working on a fix. But its been 6 months.:(
 

McRat

Diesel Hotrodder
Aug 2, 2006
11,249
26
38
64
Norco CA
www.mcratracing.com
I spoke with Guy about this today because I'm having trouble adjusting this on my '07 and a friend's '08...Worked just fine on our '02...Anyone else had any luck with a '07 or newer?

I could have sworn I did an 07, I think it was an LBZ.

Stop by if you are in the area and we can dink with it.