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18 on 38's
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616 Posts
Discussion Starter #1
Ok so see my sig, 01 1500, 5:13's, 38's
My Speedo is off by about 14-15% fast so when I'm going 84 I hit my speedlimitter. Also transmission doesn't shift as good as it could, and ABS won't let me stop quickly, and ABS turns off after driving for a while

I started a thread a while back about this.
Hypertech won't work
Black bear can't do it
Dealer can't do it

I've herd of little Speedo calibration boxes buti don't know what all I need since some say when running above 4:56 (is 4:88, 5:13, ECT) that you need an ADDITIONAL box

so what do I need to fix my abs and speedometer?

Thanks
 

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i had a 1998 z71 lifted and my abs light would come on and off and never could get it fixed. the brakes would work some times and sometimes the truck did not want to stop hardly (it would shake stopping). i hooked up a abs code scanner and i turned out three codes, but there was one code i knew that if i replaced parts if would not of fixed the problem so i just took the abs fuse out and it fixed the problem.
 

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Bad Luck is all i got.
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1,483 Posts
All my stuff works fine and I had Nelson tune mine and he fixed he as and speedo after my gear change.
 

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18 on 38's
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616 Posts
Discussion Starter #4
had a 1998 z71 lifted and my abs light would come on and off and never could get it fixed. the brakes would work some times and sometimes the truck did not want to stop hardly (it would shake stopping). i hooked up a abs code scanner and i turned out three codes, but there was one code i knew that if i replaced parts if would not of fixed the problem so i just took the abs fuse out and it fixed the problem
I know there is a way to fix it, but taking the abs fuse out in the mean time might not be a bad idea
 

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Its just my style
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1,404 Posts
I remember reading somewhere a while back that with a regular plug-in tuner, you can "trick" the trucks comp by saying you have like 4.56s and 32s or somthing like that. You'll have to look at a gear/tire chart and pick a combo that matches your current RPMs.

Found it....

******* I beleive the Hypertech programmer only allows you to program up to 35" or 36" tires, that's why I went with the Superchips programmer. It goes all the way up to 4.88's and 38" tires. To use the Hypertech, you have to "trick" the computer in your truck to think that you have 38" tires. For example programming with 4.10 gears and 34 inch tires will get you the same RPM's as if you were running 4.88's and 38" tires(this is just an example to give you an idea, but use the formula to be 100% correct). This probably sounds confusing but there were some posts about this somewhere here on these forums about this, try a search. There is some calculation formula that you can use to figure this out.
 

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1,477 Posts
Seems like all your threads are problems with your truck...you work on that damn thing more than you drive it!
 

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Respect mah authoritah!
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11,152 Posts
Seems like all your threads are problems with your truck...you work on that damn thing more than you drive it!
what happens when u have a lifted truck. lots of maintenance.
 

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Corn Star
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857 Posts
my abs light comes on when i spin leaving a parking lot or gas station, then cuts off on my next drive. and my speedo only went to 85 or 86 with 35s and 4:56, but i havent checked now that i have 37s
 

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Registered
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707 Posts
I'm running 5.13's and 37's and black bear tuned mine just fine :shrug: no abs lights and speedo is perfect.
 

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25 Posts
Not sure this would help but I had the same problem with my 08 and what i found out was it actually had two seperate computers (abs and pcm). Problem was the tire size was not correct....I had to actually measure the tire (using the rolling method) and found out that is was off about a half inch...once i put in the EXACT tire size I quit getting the dingy and lights...I hear a lot of people say they have this issue and I had it for while until I actually measured....

Also like mentioned before you may want to find out what you rpm's should be with your tire and wheel combination then you can use a differant combination (tire and gear)to come up with the same rpm
 

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18 on 38's
Joined
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616 Posts
Discussion Starter #12
I remember reading somewhere a while back that with a regular plug-in tuner, you can "trick" the trucks comp by saying you have like 4.56s and 32s or somthing like that. You'll have to look at a gear/tire chart and pick a combo that matches your current RPMs.

Found it....

******* I beleive the Hypertech programmer only allows you to program up to 35" or 36" tires, that's why I went with the Superchips programmer. It goes all the way up to 4.88's and 38" tires. To use the Hypertech, you have to "trick" the computer in your truck to think that you have 38" tires. For example programming with 4.10 gears and 34 inch tires will get you the same RPM's as if you were running 4.88's and 38" tires(this is just an example to give you an idea, but use the formula to be 100% correct). This probably sounds confusing but there were some posts about this somewhere here on these forums about this, try a search. There is some calculation formula that you can use to figure this out.
thanks this is what I was looking for, although my laptops busted and my phone won't let me search on the forum. I'll try googling it
 

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18 on 38's
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616 Posts
Discussion Starter #13
Allright, so I ordered a hypertech programmer for $50, can't beat that, I'll look for those equations to choose the right gears and tires to make it work right, If I don't find them I'll just experiment until its right
 
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