(KRUISR is the multilingual one, here, for I am just a cave man.

I fell! in some ice and was later thawed out by scientists. Your hexidecimals, and your kilometers vs. MPH, all of it! frightens and confuses me... I'm just a cave man...)

 

So the change I suggested yesterday evening was for +0.5 MPH. Don't forget your speedo and GPS are rounding to the nearest whole number. Probably won't be able to get both your speedo and cruise controls to be perfect

For an additional 0.5 MPH use 09CB, and for 1.0 MPH increase from where you are now use 09DA.

 

Exactly. I don't expect your work to be able align what the digital readout is for Cruise/SpeedControl and the speedometer dial, but as long as my GPS MPH and my speedo align, I will be more than happy, and very grateful to you.

Your help is absurdly appreciated.

I'll report back in a little bit. I go make this additional change, now.

 

Bingo! Using the bigger swing did the trick. 09CB was close, but 09DA put us right on the money!

G'dang! This is great. Thank you very much.

Does this change your relationship to the faux gearing number for after the swap to 4.10? Either way, I'll be ready to input what you suggest after this latest synchronization.

Dude!

 

Yes, I will adjust your new number because you liked the 09DA value. With the increase in tire circumference value from the 098F to 09DA we increased the circumference 75mm. If we used the number from earlier for your after gear change value you would have gotten the same 1-2 mph error. Given you liked the 09DA the best, I will revise your new line after gear change to ...

726-12-01 0177 0952 xxxx

Again, if it is too much off we can fine tune it to your liking.

 

That you are willing to see this through to the end is amazing.

But, seriously. And I'll say it again: Thank you.



Oh, and I cleared the DTCs in the BCM.

 

Four days later...


IT LIVES.

Gotta take it easy on it for 500 miles but the gear swap and diff install went very well. The only noise coming from my truck that I could hear from the driver's seat was the burble of the 5.0 through an all-3" exhaust and the hum of an aggressive tire. The rear axle was silent. Love the new gearing.

With KRUISR's tremendous help, I was able to program his latest suggestion and we landed very close to target. Speedo reads 2 MPH slow at 4 and almost 3 MPH slow at 60 (which was held for one-half mile before reducing speeds back down to 40- 50 where conditions permitted). I kept to mostly surface streets til about halfway through the 44 mile hop home. Had dinner w/ an old car club buddy. Let the axle cool for an hour, then it was back to the westerly route home.

The gear installer suggested to go easy but to vary MPH and even suggested the freeway for two exits then back to surface streets. It was a comfortable ride home and I'm satisfied that the job was done not only "right" but well, by an experienced gear man.

Can't wait to try a couple more hexidecimal inputs! to align the speedo w/ GPS.

 

So speedo reading 2/3 MPH slower. We will increase the tire diameter to try and compensate. Change 0952 to 099D.

That makes your new line - 726-12-01 0177 099D xxxx

Let us know.

 

Perfect timing! I'm about to run some local errands and put a few more miles on the break-in.

Will report back.

 

Having the advantage of KRUISR's heavy lifting thus far, I was able to use his experience and results to extrapolate another 1.5 MPH worth of tire size hexadecimal code.

Bingo. We are on the money so far... but it's gonna be another week or two before might be able to sustain 70 MPH for at least one-half mile to obtain a steady GPS corroboration.

Cheers.