New Tires, and New Gears, 2010 Truck

[Gordon0652]

Just installed new 32.99" tires and 4.10 gears in my Sierra with the 4.8 4-Speed.
Trying calibrate for new tires and gears. PCM is taking the calibration but i am seeing no change in the speedometer.
I am tuning in the transmission.
Transmission Calibration => Speedo => Parameters => H0103 changed to 4.10 => Speedo Calculator => Speedo Calculator => Width 275 => Profile => 60 => Rim 20 => Apply.

Save As => Program PCM with currently loaded calibration.

Drive on the highway and see no difference.

HELP


Heres the strange part, my factory PCM says my gears are 3.73, that has to be wrong because that was no option for my truck, my truck has 3.42. Any sense?

Also i go into shift point correction:
Origional Calibration Values => Tire Diameter 31.61 => Diff. Ratio 3.73. (kept it stock)
New Calibration Values => Tire Diameter 32.99 =. Diff. Ratio 4.10 (what i installed)

And then it does not come up with a % change. Does nothing.


Please help, i am going back to college Sunday morning and need my truck calibrated by then.

[Gordon0652]

That is the factory tune.

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[Gordon0652]

AWESOME!!! not

Went to buy an engine license V2 and says my Serial # and code is incorrect! Looked at it 3 times and i entered everything right. Go figure can only expect these computers NOT to work. Looks like it wont happen before Sunday. POS!!!

[joecar]

I don't see all the speedo parameter in the trans file... can you also post the engine file.

I pm'd Tech Support regarding the incorrect serial number.

[Blacky]

AWESOME!!! not

Went to buy an engine license V2 and says my Serial # and code is incorrect! Looked at it 3 times and i entered everything right. Go figure can only expect these computers NOT to work. Looks like it wont happen before Sunday. POS!!!
What was the order number? I'll check it out for you.
Regards
Paul

[Blacky]

Looks liek you have two orders: 15679 and 15680
15679 failed
15680 succeeded

Do you want to cancel 15679?

Regards
Paul

[Blacky]

Also i go into shift point correction:
Origional Calibration Values => Tire Diameter 31.61 => Diff. Ratio 3.73. (kept it stock)
New Calibration Values => Tire Diameter 32.99 =. Diff. Ratio 4.10 (what i installed)

And then it does not come up with a % change. Does nothing.


Please help, i am going back to college Sunday morning and need my truck calibrated by then.

You should see -5.55% in the "Adjust by:" box. (as in the attached image).
You may also need to set the speedo parameters in the ECM (not just the TCM).

Regards
Paul

[Gordon0652]

Looks liek you have two orders: 15679 and 15680
15679 failed
15680 succeeded

Do you want to cancel 15679?

Regards
Paul

Yes i do! I think its working now for me.

[Gordon0652]

Someone want to take a look at these "tunes" for my gears and tires?
My speedometer is still 2-3mph slow, i will fix that tomorrow. Messed around with tire sizes all night to get it closer and closer.
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[InTruckDesign]

If you are just 2-3mph off then under the speedo calculator tab select speedo fine tuning enter values and apply.
Also you need to change both tcm speedo settings and ecm speedo settings.

[Taz]

In the TCM OS the only Speedometer setting is H0103 - final drive ratio.

In The ECM OS there are multiple parameters in the "Speedometer" folder.

Both the ECM and TCM OS should be updated.

If you are only off a little in speed (actual vs displayed), then you can use the "Speedo Fine Tuning" option in the "Speedo Calculator".

Regards,
Taz

[Gordon0652]

I have been messing around with the fine tune calculator and it does not want to calculate any values.

[Gordon0652]

I adjusted my tire size to 40" in the PCM and it did NOTHING to the speedometer

[Taz]

Haven't tuned a 2010 Sierra ... have an '08 T42 on file ... has paramater H0136 (tire revolutions) in TCM tune ... yours does not ... in your ECM file the VIN info looks odd ...

Are you running the latest version of the EFILive software / firmware ?? Given that the subject vehicle is a "new" model, the software will need to be up to date to accuartely recognize the tune.

Is this a 4wd or 2wd ?

Can you post your tire info - manufacturer, size, revs per mile, etc. ?

Can you also post the original (never modified) ECM & TCM tune files ? With an unmodified tune to start from, I would enter changes, and repost - if you want.

Something is definitely not right ...

In the back of my mind I recall something about tire diameter limitations, but I think that was with the 512Kb LS1-B PCMs ... will try and source that info ...

Regards,
Taz

[Gordon0652]

The truck is 4wd.
The tires i am running are 275/60/20 which should be 32.99" but the mfg. says they are 33.03".
Here are the factory tunes.

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[Gordon0652]

Yes, just downloaded newest software yesterday before this "tune"

[Taz]

OK ... thanks for posting the tune and tire data. What type of tire (ie. Firestone Winterforce, etc.) are they ? Just want to confirm specs from several sources - in case that is part of the problem.


Regards,
Taz

[Gordon0652]

OK ... thanks for posting the tune and tire data. What type of tire (ie. Firestone Winterforce, etc.) are they ? Just want to confirm specs from several sources - in case that is part of the problem.


Regards,
Taz

They are cooper ZEON LTZ 275/60/20. Not going "off roading" just wanted a better look.
I am still playing around with the speedo configurations and i am chasing my tail right now...

[Taz]

OK .. thanks for the tire update ... busy Saturday here ... give me a couple of hours ... and I'll repost with changes for tires and 4.10 gears.

This may not make any difference ... if there is a software / tune issue of some sort ... but at least 2 pair of eyes are better than one !

Regards,
Taz

[Gordon0652]

Thank You!!

[Taz]

Forgot to ask ... the OEM tires (that originally came on the truck) ... would appreciate knowing the manufacturer / model and size ... please


Regards,
Taz

[Gordon0652]

Goodyear ST 265/70/17
That came on the truck stock. i believe thats 31.61"

[Taz]

Last question … I promise !!!

Just reread the entire thread prior to getting started … seems like there is potential confusion about the axle gear ratio …

Would you confirm OEM options – usually an option list sticker on the inside of the glove compartment door.

GU5 – 3.23
GU6 – 3.42
GT4 – 3.73
GT5 – 4.10
G80 – locking differential (don’t need this, but thought you might be curious !)

Regards,
Taz

[Gordon0652]

Just looked:
GU6 - 3.42
G80 - Locker (not sure if i like it on the street, but on dirt roads, awesome!!!

[Taz]

OK … you weren’t kidding, that speedometer calculator did not want to play nice !

Ended up doing it 2 different ways – in one set of tune files I used the tire diameter (“Tire Diameter” in the tune name) – the other set I used the tire revolutions per mile (“Rev per Mile” in the tune name).


Given:

gears changed from 3.42 to 4.10
original tires – 31.70 diameter, 99.5 circumference, 660 revs per mile
new tires – 33.03 diameter, 103.7 circumference, 629 revs per mile

I calculated a 14% reduction in speeds was required in the applicable tables. The software calculated a 12.61 % reduction was required to the speeds in the tables – so applied a 12.61 reduction (the lesser of the two calculations).

The revolutions per mile tunes (629), assume a tire diameter of 32.06.

The tire diameter tunes (33.03), assume revolutions per mile of 610.

Obviously, only use the matching tunes in combination with each other. In the end, neither may work for you – hopefully one does !

Good luck ….

Regards,
Taz

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[Gordon0652]

I will load tomorrow morning bright and early! THANK YOU. Will let you know.

[Taz]

Just an update ...

Received a PM from Gordon0652 ... he got everything working OK ... he had to leave and return to school ... he will post an update of what worked and what didn't ... when he is able.

Regards,
Taz

[Gordon0652]

Good Morning!
I made it back to college safe last night! Truck drove awesome on the hills and mountains. I used the Tire Diameter engine/trans tune. It was acurate to 1mph which could be an error of me reading it or GPS.
One thing that i will have to change is the shift points at WOT because it shfts around 5,000 and i would like it to shift around 5,500.

Special thanks to Taz for getting me back on the road safely.


ohhh hey Professor Miller! AutoCadd sucks i rather use Inventor.

[Gordon0652]

ohhh hey Professor Miller! AutoCadd sucks i rather use Inventor.

Sorry about that, My professor was wondering what i was doing on my screen so he put my screen up on the projector...

[joecar]

lol...

Good deal :cheers: