Speedometer stopped working after changing the gear ratio to 4.56 from 3.55.
What is your question?
The speedometer started bouncing and jerking back and forth after I changed the gear ratio to 4.56 from 3.55 in my 1996 F150 4x4 XLT with 351w and automatic transmission. I recently lifted the truck 6" and it has 35x12.50R20 tires so it was a little shy on horsepower that is the reason for the gear change. The check engine light is not on and there are no engine codes. The cruise control tries to work but is has a difficult time following the speedometer and the engine revs up and down and is not steady.
What makes this problem better or worse?
Problem is constant
How long has your 1996 Ford F-150 had this problem?
Speed sensor mounted on TOP of rear differential is unhooked or damaged - possibly wiring issue but not as likely.
That seep sensor also sends signal to SPEEDOMETER as well as ABS.
Erratic idle is indicative of idle air control valve malfunction.. (IAC valve)
⚠️ Side note - assuming the ring gear has the reluctor ring for rear speed sensor in place??? ⚠️
Thank You for your help! I had the gears installed at 4Wheel Parts so I do not know if the reluctor ring was installed. My sales invoice doesn't mention any reluctor ring in the parts list
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Thank You for your help! I had the gears installed at 4Wheel Parts so I do not know if the reluctor ring was installed. My sales invoice doesn't mention any reluctor ring in the parts list