MPG Stinks after front dif and transfer case replacement

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swathdiver

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Where is the best place to get it? Been looking online but results are far and wide. Can it disable my AFM? You wouldn't happen to have a part number or link would you?
Thanks again James!

No, it cannot disable AFM but it can test it thoroughly. Bought mine from AliExpress two years ago. Fellas on here have bought them off ebay and Chinacardiags. You want the latest software, 33.004 and a seller with good reviews and or one that has a sold a bunch of them.
 

thompsoj22

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No, it cannot disable AFM but it can test it thoroughly. Bought mine from AliExpress two years ago. Fellas on here have bought them off ebay and Chinacardiags. You want the latest software, 33.004 and a seller with good reviews and or one that has a sold a bunch of them.


also got mine from aliexpress $275 to my door fedex.
 
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Jolly Roger

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Ok, had my son place his cell phone under the truck while I drove slowly over it...
My front drive shaft going to the transfer case is turning.
I'm not in four wheel drive. Is this correct operation?
 

thompsoj22

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Ok, had my son place his cell phone under the truck while I drove slowly over it...
My front drive shaft going to the transfer case is turning.
I'm not in four wheel drive. Is this correct operation?[/QUO

yes that is normal, the shaft allways spins because you dont have the style hubs that allow axle disengagement. ask your son to go for a ride with you and find a smooth quiet culdesac/parking lot and with the windows down do a smooth 360 degree turn in both directions, there should be no chirping/lurching in 2wd. you have to rule out the drivetrain and than i think your mpg may reveal itself to be engine related in some way? hey does your sons phone still work after "i drove over it slowly" id like to do the same thing to my daughters phone! lol
 
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Jolly Roger

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I'm on it John! And thank you for the suggestion!
I'm slammed most of the day today but I surely can find time for this test and get back to you with the results asap.

I'm 100% positive that its not in 4-wheel drive but I'm pretty sure that even in 2-wheel drive the frt diff binds a bit and makes a whining noise when turning sharply. Ill pay close attention today and report back!

And yes, when I pulled up behind Home depot yesterday and told my son to get out and put his phone under my truck, he had those dear in the headlight eye's. :D
 
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Jolly Roger

Jolly Roger

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Test complete.
Took it to a parking lot and drove in the tightest circle possible in both directions. Nothing! No squeaks, no binding no lurching notta!

But something did come to mind:
When replacing the transfer case they said the the O2 sensor wire was wrapped around a drive shaft. They repaired it. I cant see any new codes on my dash because the CIL stays on all the time due to a gas tank purge valve error.
Could a faulty o2 sensor/wire cause such a drastic mpg loss?
 
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Rocket Man

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Test complete.
Took it to a parking lot and drove in the tightest circle possible in both directions. Nothing! No squeaks, no binding no lurching notta!

But something did come to mind:
When replacing the transfer case they said the the O2 sensor wire was wrapped around a drive shaft. They repaired it. I cant see any new codes on my dash because the CIL stays on all the time due to a gas tank purge valve error.
Could a faulty o2 sensor/wire cause such a drastic mpg loss?
Oh yeah. The ECU uses O2 data to determine fuel mixture.
 
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Jolly Roger

Jolly Roger

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I dont currently have a scanner but maybe one of the auto parts places will plug up for me real quick....but with my luck I can just about guarantee that no o2 code will return. That would be way too easy. lol
 

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