I have a pinging problem in my 2004 sohc 4.0. Just about any hill from 30 mph on up to highway speed causes my valves to rattle or ping. Premium 93 octane fuel solves the problem, but the engine should run fine on regular. I have about 83k miles.

Any ideas?

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2004 super cab, 4 door xlt with appearance package and 4.0 cammer V-6 with auto trans and 2wd fitted with a Leer topper. Sounds via Alpine head unit and power pack through infinity Kappa components front and Kappas rear.

Its caused from detonation in the cylinder(s). Is there a loss in performance? Is your engine running hot? Check the timing? Keep putting high octane fuel in it until you find the problem. Detonation can ruin the engine.

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2005 FX4 OffRoad
4" suspension lift
3" body lift
Cat Back Magnaflow Exhaust
16" Pro Comp Extreme Alloy Wheels
315/75 R16 Kuhmo Road Venture A/T

^ yep, detonation sucks, my bud has a crown vic motor that suffered from it, not good.

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99 xlt supercab xlt 4.0l ohv 4x4
mirror tint all around
2 piaa 580 lights and 2 220w dick cepek lights
100w pa system
2"front/1.5 rear lift
1 10" pioneer champion sub/ 1800w jl amp/ kenwood HU
31x10.5x15 Pegasus A/T