There is a high pitched noise when I am accelerating into what sounds like high rpms. (No tach installed) is it bad? I have a 99 Durango with a 318 and dose this in the 3500+ range.
SL6 4bbl Holley 727 auto

Check to see if someone installed a turbocharger or supercharger while you weren't looking.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Check the oil level in the rear end.
DD

I wish they had but how to check the oil level

Do you mean, "How do I check the oil level in the rear axle of my 99 Durango?"

If so, there will be a fill plug on the side of the center section of the axle. With the truck sitting level, remove the plug and stick your finger in the hole. The axle gear lube oil should be even with the bottom of the fill hole.

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Casually looking for a Clifford hyperpak intake for cheap.

Not of the Durango. I ment the D150 I was referring to the Durango as in it makes the same noise during 3500+ rmps

The same instructions apply.

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Casually looking for a Clifford hyperpak intake for cheap.

Level meaning not jacked up

Level meaning parked on flat ground with the suspension holding the full weight of the vehicle. If the truck is on a hoist that lifts the frame and lets the axle drop and dangle from the rear springs, then the oil level should be about 1/4 inch below the plug hole. If you have any question then just make sure the oil is between the bottom of the fill hole and 1/4 inch below the bottom of the hole.

Again, I thought you said you had a shop manual for your truck?

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Casually looking for a Clifford hyperpak intake for cheap.

I do but can't seem to remember where I placed it last

Can you describe this high pitched noise any better? Is it a smooth whistle or a grinding high pitched noise or shrieking/squeaking noise, or what?

It's like a whistle I guess I hear it only when in holding the petal to the floor or switching gears only in drive. When in park I can rev all I want and no noise

Does the whistle change pitch when the truck shift gears?
Do you have an aftermarket sound system installed?

I ask, because fairly often the alternator will make an electronically-induced whine or whistle in the stereo as you described. Most times, it's not very loud, but is noticable.

Roger

I have an aftermarket radio and equalizer. It was a sound system but took it out months ago

To remove the oil plug in the rear differential you can use a 1/2 rachet (at least in my car). Plug it directly on the plug's square notch, or use an extension if it is too difficult to reach. Then, check the oil level is at the plug's hole bottom (almost overflowing). if not fill it up to that level. Use differential oil.

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/6 Dodge Charger 69
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