rear end swap

2005 DODGE RAM
120,000 MILES • 5.7L • V8 • RWD • AUTOMATIC
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MASOY
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  • 10 POSTS
Have swapped rear ends in truck. I went from the original rear end axle assembly which had 3.21 ratio to 3.92. Do i need to reprogram the computer to the higher gear ratio? If so how much would that cost? or can i rent a programmer and do it myself?
Apr 19, 2017 at 5:14 PM
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WRENCHTECH
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No, you cannot rent a programmer. Either the dealer or some high tech independents will have the equipment. Average cost about $150.00.
Apr 19, 2017 at 6:08 PM
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STEVE W.
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  • 15,200 POSTS
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Yes the PCM will need to be reprogrammed to correct the speedometer, shift pattern and engine management to match the new ratio.
Cost depends on who does the work so you would want to call a couple places to get an accurate price. I do not know of anyone who rents programming equipment, far to easy to turn a working PCM into a brick.
Apr 19, 2017 at 6:09 PM
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