2004 Chevrolet Tahoe oil pressure gauge

That may be normal, especially if the pressure reads lower in hot weather or when the engine has warmed up. It is also somewhat common for the sending units to cause that. It can respond too much to small changes in pressure. A mechanic can connect a mechanical pressure gauge to see what the actual pressure is under different conditions. If it doesn't vary too much you might install a new sending unit. If the pressure does drop off quite a bit at lower engine speeds the oil could be diluted with raw gas from a previous running problem, or someone might have used oil that's too light at the last oil change.

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