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minytrker
February 9th, 2012, 04:20 PM
Has anyone figured out the amount you can adjust the speedometer where you wont get an ABS code on E38 trucks? What is the best way to correct the speedometer with EFI Live? If I have a tech II can I correct the speedometer stuff in the ABS module without the tech II being online if its up to date?
minytrker
February 12th, 2012, 01:18 PM
anyone
minytrker
February 16th, 2012, 01:57 PM
no is correcting speedometers out there?
swingtan
February 16th, 2012, 02:32 PM
I'm not sure what the problem is. we don't have any E38 trucks in OZ, but cars have gone from 3:07:1 diff gears to 3.9:1 with no issues. From memory, you may need to alter both the TCM and ECM settings though ( for auto models ). I haven't done one for a while now.

Simon
GMPX
February 16th, 2012, 02:46 PM
Simon, I hear of this problem on the Diesel trucks too, it's something to do with once the tire size goes over a certain figure the ABS throws a code, I am sure TechII is the only solution.
swingtan
February 16th, 2012, 03:01 PM
Ahh, is this a rear tyre vs front tyre discrepancy? So the actual wheel speeds would be significantly different between the front and rear wheel? I can see this as causing big ABS issues. Or it might just be an ABS rational check that assumes that at a certain speed, the ABS sensors should be giving a certain number of pulses. Fitting larger wheels may make the ABS module think the wheels are sliding as the pulses ar too slow for the given road speed.
turbo_bu
February 17th, 2012, 06:15 AM
This is some info that I have for the diesel trucks, but I would think that all the trucks would suffer the same issue.

http://www.duramaxdiesels.com/forum/showthread.php?t=944&highlight=ABS+Tire+Size
minytrker
February 17th, 2012, 06:37 PM
This is some info that I have for the diesel trucks, but I would think that all the trucks would suffer the same issue.

http://www.duramaxdiesels.com/forum/showthread.php?t=944&highlight=ABS+Tire+Size


Thanks!
Thats exactly what I was looking for. I knew it had to be in the 34 or 35 inch range just from past experience but I wanted to see what others had found.
isak81
February 25th, 2012, 01:43 PM
So you cant adjust the speedometer at all?
GMPX
February 26th, 2012, 09:56 AM
Yes you can but at some point (as shown in that thread) the ABS module becomes a problem.
isak81
February 26th, 2012, 12:26 PM
Yes you can but at some point (as shown in that thread) the ABS module becomes a problem.
Well I tried it on my friends truck and I get the abs code. It's an 2007 Silverado with 275/60/20. Were do you change it,
in the transmission or engine?
swingtan
February 26th, 2012, 01:00 PM
I think the answer is "neither, if you are trying to fix the ABS code".

My understanding is that the ABS settings are not controlled by either the ECM or the TCM, so no amount of "tuning" will stop the ABS code being generated. This is why it need to be done using a Tech-II and directly accessing the ABS settings. I've never tried it, but that's how I read all the info in the posts.


Simon
isak81
February 26th, 2012, 04:34 PM
Well I did both and tried different settings but got the code. The way I understand it,
if the tires get over 36-37 inches tall it becomes a problem. These are 32 inches.
I think I'm not adjusting the right table.
turbo_bu
February 28th, 2012, 06:23 AM
Not sure of the limits in the ABS controller, but thinking it through, wonder if it has to do with too few of pulses at low speeds. If you have a big tire, then for a given speed, there would only be a fraction of the number of pulses coming into the ABS controller. This would result in a lower resolution vehicle speed channel which would cause the controller fits. Assuming the biggest problems are trying to see when the tire stops rotating thus indicating the need for ABS.

Anyone make tone wheels (the toother rings) that go on at the wheel hubs with more teeth on them? Of course, this would still require "faking" out the ABS controller so that it would know how fast everything is moving, but could remove the limitation of big tires (e.g. greater than 38" tall).
isak81
February 29th, 2012, 02:26 PM
Alright. I have experience with a LS1B ECM.
I know how to calibrate the speedo on it.
What is the correct way to do it on a E38?
ls1mike
May 9th, 2012, 01:31 PM
Working on a 2012 5.3 truck, dash speedo not matching my edits? Seems like everything I've been trying isn't making a difference? Dash: 65mph reality: 72 No ABS lights or errors. 35" tires... strange? Any input that might save me some time would be great.
isak81
May 9th, 2012, 01:47 PM
Working on a 2012 5.3 truck, dash speedo not matching my edits? Seems like everything I've been trying isn't making a difference? Dash: 65mph reality: 72 No ABS lights or errors. 35" tires... strange? Any input that might save me some time would be great.

I changed H0105. Find % that you are off. Then times it and add or subtract
ls1mike
May 10th, 2012, 02:57 AM
Perfect, thank you.
koryenger
May 22nd, 2012, 12:12 PM
Working on a 2012 5.3 truck, dash speedo not matching my edits? Seems like everything I've been trying isn't making a difference? Dash: 65mph reality: 72 No ABS lights or errors. 35" tires... strange? Any input that might save me some time would be great.

I am having the same problem. 2011 Suburban 6l80 and everything I try is not making a change. I went +/- 10...20...30...40% on the H0105, messed with gear ratios. The vehicle has a 6.0 gear in it and 40 inch tires. Basically what I am seeing on a scanner is almost double of how fast the vehicle is going. Anyone have any suggestion on this?
koryenger
May 22nd, 2012, 03:38 PM
I forgot to mention, this vehicle isnt using a gm ABS module, so the tech 2 solution wont work.
VEGASROBBI
June 6th, 2012, 07:32 AM
I am having the same problem. 2011 Suburban 6l80 and everything I try is not making a change. I went +/- 10...20...30...40% on the H0105, messed with gear ratios. The vehicle has a 6.0 gear in it and 40 inch tires. Basically what I am seeing on a scanner is almost double of how fast the vehicle is going. Anyone have any suggestion on this?

I have had no luck with two 2011 Silverado's correcting the VSS. Any changes I make to the speedo parameters or gear ratio's have no effect; similar, to the problem I had a few years ago with the 09's.

I ended up using HPT and Hypertech to calibrate the VSS on these vehicles.

Any help is appreciated.
joecar
June 6th, 2012, 08:48 AM
I have had no luck with two 2011 Silverado's correcting the VSS. Any changes I make to the speedo parameters or gear ratio's have no effect; similar, to the problem I had a few years ago with the 09's.

I ended up using HPT and Hypertech to calibrate the VSS on these vehicles.

Any help is appreciated.Which V7/V8 software build versions do you have...?
VEGASROBBI
June 6th, 2012, 09:55 AM
Which V7/V8 software build versions do you have...?

V7.5.7 (Build 209)
V8.2.1 (Build 200)

Thanks
Tordne
June 7th, 2012, 02:30 PM
Have you tried making the changes to the same tables in the TCM at all? That's just based on messing with my E38/T43 vehicle some time back... Speed calibration is a bit of a dark art I'm afraid.
koryenger
June 8th, 2012, 03:05 AM
Have you tried making the changes to the same tables in the TCM at all? That's just based on messing with my E38/T43 vehicle some time back... Speed calibration is a bit of a dark art I'm afraid.

Tried it all...Vegasrobbie hit the nail on the head...Im affraid its just not possible at this point in time...